1.1.3.1. Internet/IPv6 history of the author

• 1993: I got in contact with the Internet using console based e-mail and news client (e.g. look for "e91abier" on groups.google.com, that's me).

• 1996: I got a request for designing a course on IPv6, including a workshop with the Linux operating system.

• 1997: Started writing a guide on how to install, configure and use IPv6 on Linux systems, called IPv6 & Linux - HowTo (see IPv6 & Linux - HowTo/History for more information).

• 2001: Started writing this new Linux IPv6 HOWTO.

1.1.3.2. Contact

The author can be contacted via e-mail at <pb at bieringer dot de> and also via his homepage.

He's currently living in Munich [northern part of Schwabing] / Bavaria / Germany (south) / Europe (middle) / Earth (surface/mainland).

1.3.2.1. Major history

2001-11-30: Starting to design new HOWTO.

2002-01-02: A lot of content completed, first public release of chapter 1 (version 0.10).

2002-01-14: More completed, some reviews, public release of the whole document (version 0.14).

2002-08-16: Polish translation is in progress

2002-10-31: Chinese translation is available (see Translations for more)

2002-11-10: German translation is in progress

2003-02-10: German translation is available

2003-04-09: French translation is in progress

2003-05-09: French translation is available

2003-08-15: Spanish translation is in progress

2003-10-16: Italian translation is in progress

1.3.2.2. Full history

See revision history at the end of this document.

1.4.1.1. Taiwanese

A Taiwanese translation by Burma Chen <expns at yahoo dot com> (announced to me at 2002-10-31) can be found on the CLDP: http://cldp.linuxforum.net/Linux-IPv6-HOWTO.html. It's a snapshot translation, don't know whether kept up-to-date.

1.4.1.2. Polish

Since 2002-08-16 a Polish translation was started and is still in progress by Lukasz Jokiel <Lukasz dot Jokiel at klonex dot com dot pl>. Taken source: CVS-version 1.29 of LyX file, which was source for howto version 0.27.

1.4.1.3. German

With 2002-11-10 a German translation was started by Georg Käfer <gkaefer at gmx dot at> and the first public version was published 2003-02-10. It's originally available on Deep Space 6 at http://mirrors.deepspace6.net/Linux+IPv6-HOWTO-de/ (mirrored e.g. on http://mirrors.bieringer.de/Linux+IPv6-HOWTO-de/). This version will stay up-to-date as much as possible.

1.4.1.4. French

With 2003-04-09 a French translation was started by Michel Boucey <mboucey at free dot fr> and the first public version was published 2003-05-09. It's originally available on Deep Space 6 at http://mirrors.deepspace6.net/Linux+IPv6-HOWTO-fr/ (mirrored e.g. on http://mirrors.bieringer.de/Linux+IPv6-HOWTO-fr/).

1.4.1.5. Spanish

With 2003-08-15 a Spanish translation was started by Eduardo Collado <edu at eduangi dot com>.

1.4.1.6. Italian

With 2003-10-16 a Italian translation was started by Michele Ferritto <m dot ferritto at virgilio dot it> for the ILDP (Italian Linux Documentation Project).

1.4.1.7. Japanese

On 2003-05-14 Shino Taketani <shino_1305 at hotmail dot com> send me a note that he planned to translate the HowTo into Japanese.

1.5.1.1. Code line wrapping

Code line wrapping is done using selfmade utility "lyxcodelinewrapper.pl", you can get it from CVS for your own usage: TLDP-CVS / users / Peter-Bieringer

1.5.1.2. SGML generation

SGML is generated using export function in LyX.

Also some fixes are have to be made to create proper SGML code (see also here for the Perl programs TLDP-CVS / users / Peter-Bieringer):

• Export of LyX table does not create proper "colspan" tags - tool for fixing: "sgmllyxtabletagfix.pl" (fixed since LyX 1.2.0)

• LyX sometimes uses special left/right entities for quotes instead the normal one, which will still exist in generated HTML. Some browsers don't parse this very well (known: Opera 6 TP 2 or Konqueror) - tool for fixing: "sgmllyxquotefix.pl"

1.5.2.1. Master index page

Generally, a reference to the master index page is recommended.

1.5.2.2. Dedicated pages

Because the HTML pages are generated out of the SGML file, the HTML filenames turn out to be quite random. However, some pages are tagged in LyX, resulting in static names. These tags are useful for references and shouldn't be changed in the future.

If you think that I have forgotten a tag, please let me know, and I will add it.

1.6.1.1. Linux IPv6 FAQ/HOWTO (outdated)

The first IPv6 related document was written by Eric Osborne and called Linux IPv6 FAQ/HOWTO (please use it only for historical issues). Latest version was 3.2.1 released July, 14 1997.

Please help: if someone knows the date of birth of this HOWTO, please send me an e-mail (information will be needed in "history").

1.6.1.2. IPv6 & Linux - HowTo (maintained)

There exists a second version called IPv6 & Linux - HowTo written by me (Peter Bieringer) in pure HTML. It was born April 1997 and the first English version was published in June 1997. I will continue to maintain it, but it will slowly fade (but not full) in favour of the Linux IPv6 HOWTO you are currently reading.

1.6.1.3. Linux IPv6 HOWTO (this document)

Because the IPv6 & Linux - HowTo is written in pure HTML it's not really compatible with the The Linux Documentation Project (TLDP). I (Peter Bieringer) got a request in late November 2001 to rewrite the IPv6 & Linux - HowTo in SGML. However, because of the discontinuation of that HOWTO (Future of IPv6 & Linux - HowTo), and as IPv6 is becoming more and more standard, I decided to write a new document covering basic and advanced issues which will remain important over the next few years. More dynamic and some advanced content will be still found further on in the second HOWTO (IPv6 & Linux - HowTo).

1.7.1.1. Shortcuts

1.7.2.1. Long code line wrapping signal char

The special character "¬" is used for signaling that this code line is wrapped for better viewing in PDF and PS files.

1.7.2.2. Placeholders

In generic examples you will sometimes find the following:

<myipaddress>
    

For real use on your system command line or in scripts this has to be replaced with relevant content (removing the < and > of course), the result would be e.g.

1.2.3.4
    

1.7.2.3. Commands in the shell

Commands executable as non-root user begin with $, e.g.

$ whoami
    

Commands executable as root user begin with #, e.g.

# whoami
    

1.8.1.1. Experience with Unix tools

You should be familiar with the major Unix tools e.g. grep, awk, find, ... , and know about their most commonly used command-line options.

1.8.1.2. Experience with networking theory

You should know about layers, protocols, addresses, cables, plugs, etc. If you are new to this field, here is one good starting point for you: linuxports/howto/intro_to_networking

1.8.1.3. Experience with IPv4 configuration

You should definitely have some experience in IPv4 configuration, otherwise it will be hard for you to understand what is really going on.

1.8.1.4. Experience with the Domain Name System (DNS)

Also you should understand what the Domain Name System (DNS) is, what it provides and how to use it.

1.8.1.5. Experience with network debugging strategies

You should at least understand how to use tcpdump and what it can show you. Otherwise, network debugging will very difficult for you.

3.1.3.1. IPv4-mapped IPv6 address

IPv4-only IPv6-compatible addresses are sometimes used/shown for sockets created by an IPv6-enabled daemon, but only binding to an IPv4 address.

These addresses are defined with a special prefix of length 96 (a.b.c.d is the IPv4 address):

0:0:0:0:0:ffff:a.b.c.d/96
    

or in compressed format

::ffff:a.b.c.d/96
    

For example, the IPv4 address 1.2.3.4 looks like this:

::ffff:1.2.3.4
    

3.1.3.2. IPv4-compatible IPv6 address

Used for automatic tunneling (RFC 2893 / Transition Mechanisms for IPv6 Hosts and Routers), which is being replaced by 6to4 tunneling.

0:0:0:0:0:0:a.b.c.d/96
    

or in compressed format

::a.b.c.d/96
    

3.2.3.1. 6bone test addresses

These were the first global addresses which were defined and in use. They all start with

3ffe:
    

Example:

3ffe:ffff:100:f102::1
    

A special 6bone test address which will be never be globally unique begins with

3ffe:ffff: 
    

and is mostly shown in examples, because if real addresses are shown, its possible for someone to do a copy & paste to their configuration files. Thus inadvertently causing duplicates on a globally unique address. This would cause serious problems for the original host (e.g. getting answer packets for request that were never sent). You can still apply for one of these prefixes, see here How to join 6bone. Also some tunnel brokers still distribute 6bone test address prefixes.

3.2.3.2. 6to4 addresses

These addresses, designed for a special tunneling mechanism [RFC 3056 / Connection of IPv6 Domains via IPv4 Clouds and RFC 2893 / Transition Mechanisms for IPv6 Hosts and Routers], encode a given IPv4 address and a possible subnet and begin with

2002:
    

For example, representing 192.168.1.1/5:

2002:c0a8:0101:5::1
    

A small shell command line can help you generating such address out of a given IPv4 one:

ipv4="1.2.3.4"; sla="5"; printf "2002:%02x%02x:%02x%02x:%04x::1" `echo $ipv4
¬ | tr "." " "` $sla
    

See also tunneling using 6to4 and information about 6to4 relay routers.

3.2.3.3. Assigned by provider for hierarchical routing

These addresses are delegated to Internet service providers (ISP) and begin with

2001:
    

Prefixes to major (backbone owning) ISPs are delegated by local registries and currently they assign to them a prefix with length 35.

Major ISPs normally delegate to minor ISPs a prefix with length 48.

3.2.4.1. Multicast scopes

Multicast scope is a parameter to specify the maximum distance a multicast packet can travel from the sending entity.

Currently, the following regions (scopes) are defined:

• ffx1: node-local, packets never leave the node.

• ffx2: link-local, packets are never forwarded by routers, so they never leave the specified link.

• ffx5: site-local, packets never leave the site.

• ffx8: organization-local, packets never leave the organization (not so easy to implement, must be covered by routing protocol).

• ffxe: global scope.

• others are reserved

3.2.4.2. Multicast types

There are many types already defined/reserved (see RFC 2373 / IP Version 6 Addressing Architecture for details). Some examples are:

• All Nodes Address: ID = 1h, addresses all hosts on the local node (ff01:0:0:0:0:0:0:1) or the connected link (ff02:0:0:0:0:0:0:1).

• All Routers Address: ID = 2h, addresses all routers on the local node (ff01:0:0:0:0:0:0:2), on the connected link (ff02:0:0:0:0:0:0:2), or on the local site (ff05:0:0:0:0:0:0:2)

3.2.4.3. Solicited node link-local multicast address

Special multicast address used as destination address in neighborhood discovery, because unlike in IPv4, ARP no longer exists in IPv6.

An example of this address looks like

ff02::1:ff00:1234
    

Used prefix shows that this is a link-local multicast address. The suffix is generated from the destination address. In this example, a packet should be sent to address "fe80::1234", but the network stack doesn't know the current layer 2 MAC address. It replaces the upper 104 bits with "ff02:0:0:0:0:1:ff00::/104" and leaves the lower 24 bits untouched. This address is now used `on-link' to find the corresponding node which has to send a reply containing its layer 2 MAC address.

3.2.5.1. Subnet-router anycast address

A simple example for an anycast address is the subnet-router anycast address. Assuming that a node has the following global assigned IPv6 address:

3ffe:ffff:100:f101:210:a4ff:fee3:9566/64  <- Node's address
    

The subnet-router anycast address will be created blanking the suffix (least significant 64 bits) completely:

3ffe:ffff:100:f101::/64  <- subnet-router anycast address
    

3.3.1.1. Privacy problem with automatically computed addresses and a solution

Because the "automatically computed" host part is globally unique (except when a vendor of a NIC uses the same MAC address on more than one NIC), client tracking is possible on the host when not using a proxy of any kind.

This is a known problem, and a solution was defined: privacy extension, defined in RFC 3041 / Privacy Extensions for Stateless Address Autoconfiguration in IPv6 (there is also already a newer draft available: draft-ietf-ipngwg-temp-addresses-*.txt). Using a random and a static value a new suffix is generated from time to time. Note: this is only reasonable for outgoing client connections and isn't really useful for well-known servers.

4.1.2.1. Automatically loading of module

Its possible to automatically load the IPv6 module on demand. You only have to add following line in the configuration file of the kernel module loader (normally /etc/modules.conf or /etc/conf.modules):

alias net-pf-10 ipv6  # automatically load IPv6 module on demand
    

It's also possible to disable automatically loading of the IPv6 module using following line

alias net-pf-10 off   # disable automatically load of IPv6 module on demand
    

Additional note: in future kernels (newer 2.5 series and above), the module loader mechanism was changed. The new configuration file has to be named /etc/modprobe.conf instead of /etc/modules.conf but there is a translate-script available. For further details see module-init-tool.

4.1.3.1. Compiling a vanilla kernel

More detailed hints about compiling an IPv6-enabled kernel can be found e.g. on IPv6-HOWTO-2#kernel.

Note: you should use whenever possible kernel series 2.4.x or above, because the IPv6 support in series 2.2.x is not so in current state and needs some patches for ICMPv6 and 6to4 support (can be found on kernel series 2.2.x IPv6 patches).

4.1.3.2. Compiling a kernel with USAGI extensions

Same as for vanilla kernel, only recommend for advanced users, which are already familiar with IPv6 and kernel compilation. See also USAGI project / FAQ and Obtaining the best IPv6 support with Linux (Article) (Mirror).

4.1.4.1. Currently known never "IPv6 capable links"

• Serial Line IP (SLIP, RFC 1055 / SLIP), should be better called now to SLIPv4, device named: slX

• Parallel Line IP (PLIP), same like SLIP, device names: plipX

• ISDN with encapsulation rawip, device names: isdnX

4.1.4.2. Currently known "not supported IPv6 capable links"

• ISDN with encapsulation syncppp, device names: ipppX (design issue of the ipppd, will be merged into more general PPP layer in kernel series 2.5.x)

4.3.1.1. Specifying interface for IPv6 ping

Using link-local addresses for an IPv6 ping, the kernel does not know through which (physically or virtual) device it must send the packet - each device has a link-local address. A try will result in following error message:

# ping6 fe80::212:34ff:fe12:3456 
connect: Invalid argument
    

In this case you have to specify the interface additionally like shown here:

# ping6 -I eth0 -c 1 fe80::2e0:18ff:fe90:9205 
PING fe80::212:23ff:fe12:3456(fe80::212:23ff:fe12:3456) from
¬ fe80::212:34ff:fe12:3478 eth0: 56 data bytes 
64 bytes from fe80::212:23ff:fe12:3456: icmp_seq=0 hops=64 time=445 usec
--- fe80::2e0:18ff:fe90:9205 ping statistics --- 
1 packets transmitted, 1 packets received, 0% packet loss round-trip
¬ min/avg/max/mdev = 0.445/0.445/0.445/0.000 ms
    

4.3.1.2. Ping6 to multicast addresses

An interesting mechanism to detect IPv6-active hosts on a link is to ping6 to the link-local all-node multicast address:

# ping6 -I eth0 ff02::1 PING ff02::1(ff02::1) from fe80:::2ab:cdff:feef:0123
¬ eth0: 56 data bytes
64 bytes from ::1: icmp_seq=1 ttl=64 time=0.104 ms
64 bytes from fe80::212:34ff:fe12:3450: icmp_seq=1 ttl=64 time=0.549 ms (DUP!) 
    

Unlike in IPv4, where replies to a ping on the broadcast address can be disabled, in IPv6 currently this behavior cannot be disable except by local IPv6 firewalling.

4.3.4.1. IPv6 ping to 3ffe:ffff:100:f101::1 native over a local link

# tcpdump -t -n -i eth0 -s 512 -vv ip6 or proto ipv6 
tcpdump: listening on eth0 
3ffe:ffff:100:f101:2e0:18ff:fe90:9205 > 3ffe:ffff:100:f101::1: icmp6: echo
¬ request (len 64, hlim 64) 
3ffe:ffff:100:f101::1 > 3ffe:ffff:100:f101:2e0:18ff:fe90:9205: icmp6: echo
¬ reply (len 64, hlim 64)
    

4.3.4.2. IPv6 ping to 3ffe:ffff:100::1 routed through an IPv6-in-IPv4-tunnel

1.2.3.4 and 5.6.7.8 are tunnel endpoints (all addresses are examples)

# tcpdump -t -n -i ppp0 -s 512 -vv ip6 or proto ipv6 
tcpdump: listening on ppp0 
1.2.3.4 > 5.6.7.8: 2002:ffff:f5f8::1 > 3ffe:ffff:100::1: icmp6: echo request
¬ (len 64, hlim 64) (DF) (ttl 64, id 0, len 124) 
5.6.7.8 > 1.2.3.4: 3ffe:ffff:100::1 > 2002:ffff:f5f8::1: icmp6: echo reply (len
¬ 64, hlim 61) (ttl 23, id 29887, len 124) 
1.2.3.4 > 5.6.7.8: 2002:ffff:f5f8::1 > 3ffe:ffff:100::1: icmp6: echo request
¬ (len 64, hlim 64) (DF) (ttl 64, id 0, len 124) 
5.6.7.8 > 1.2.3.4: 3ffe:ffff:100::1 > 2002:ffff:f5f8::1: icmp6: echo reply (len
¬ 64, hlim 61) (ttl 23, id 29919, len 124)
    

4.5.3.1. openssh

Current versions of openssh are IPv6-ready. Depending on configuring before compiling it has two behavior.

• --without-ipv4-default: the client tries an IPv6 connect first automatically and fall back to IPv4 if not working

• --with-ipv4-default: default connection is IPv4, IPv6 connection must be force like following example shows

$ ssh -6 ::1 
user@::1's password: ****** 
[user@ipv6host user]$
    

If your ssh client doesn't understand the option "-6" then it's not IPv6-enabled, like most ssh version 1 packages.

4.5.3.2. ssh.com

SSH.com's SSH client and server is also IPv6 aware now and is free for all Linux and FreeBSD machine regardless if used for personal or commercial use.

4.5.4.1. URLs for testing

A good starting point for browsing using IPv6 is http://www.kame.net/. If the turtle on this page is animated, the connection is via IPv6, otherwise the turtle is static.

4.7.1.1. Q: Cannot ping6 to link-local addresses

Error message: "connect: Invalid argument"

Kernel doesn't know, which physical or virtual link you want to use to send such ICMPv6 packets. Therefore it displays this error message.

Solution: Specify interface like: "ping6 -I eth0 fe80::2e0:18ff:fe90:9205", see also program ping6 usage.

4.7.1.2. Q: Cannot ping6 or traceroute6 as normal user

Error message: "icmp socket: Operation not permitted"

These utilities create special ICMPv6 packets and send them out. This is done by using raw sockets in the kernel. But raw sockets can only be used by the "root" user. Therefore normal users get such error message.

Solution: If it's really needed that all users should be able to use these utilities, you can add the "suid" bit using "chmod u+s /path/to/program", see also program ping6 usage. If not all users should be able to, you can change the group of the program to e.g. "wheel", add these power users to this group and remove the execution bit for other users using "chmod o-rwx /path/to/program". Or configure "sudo" to enable your security policy.

5.1.2.1. IPv6-in-IPv4 tunnel interfaces

These interfaces are normally named sitx. The name sit is a shortcut for Simple Internet Transition. This device has the capability to encapsulate IPv6 packets into IPv4 ones and tunnel them to a foreign endpoint.

sit0 has a special meaning and cannot be used for dedicated tunnels.

5.1.2.2. PPP interfaces

PPP interfaces get their IPv6 capability from an IPv6 enabled PPP daemon.

5.1.2.3. ISDN HDLC interfaces

IPv6 capability for HDLC with encapsulation ip is already built-in in the kernel

5.1.2.4. ISDN PPP interfaces

ISDN PPP interfaces (ippp) aren't IPv6 enabled by kernel. Also there are also no plans to do that because in kernel 2.5.+ they will be replaced by a more generic ppp interface layer.

5.1.2.5. SLIP + PLIP

Like mentioned earlier, this interfaces don't support IPv6 transport (sending is OK, but dispatching on receiving don't work).

5.1.2.6. Ether-tap device

Ether-tap devices are IPv6-enabled and also stateless configured. For use, the module "ethertap" has to be loaded before.

5.1.2.7. tun devices

Currently not tested by me.

5.1.2.8. ATM

01/2002: Aren't currently supported by vanilla kernel, supported by USAGI extension

5.1.2.9. Others

Did I forget an interface?...

7.6.1.1. Clients (not routing any packet!)

Client can setup a default route like prefix "::/0", they also learn such route on autoconfiguration e.g. using radvd on the link like following example shows:

# ip -6 route show | grep ^default
default via fe80::212:34ff:fe12:3450 dev eth0 proto kernel metric 1024 expires
¬ 29sec mtu 1500 advmss 1440
    

7.6.1.2. Routers in case of packet forwarding

Current mainstream Linux kernel (at least <= 2.4.17) don't support default routes. You can set them up, but the route lookup fails when a packet should be forwarded (normal intention of a router).

Therefore at this time "default routing" can be setup using the currently only global address prefix "2000::/3".

The USAGI project already supports this in their extension with a hack.

Note: take care about default routing without address filtering on edge routers. Otherwise unwanted multicast or site-local traffic leave the edge.

9.1.3.1. Generation of 6to4 prefix

The 6to4 address is defined like following (schema is taken from RFC 3056 / Connection of IPv6 Domains via IPv4 Clouds):

|   3+13   |    32     |    16  |            64 bits             | 
+---+------+-----------+--------+--------------------------------+ 
|  FP+TLA  |  V4ADDR   | SLA ID |           Interface ID         | 
|  0x2002  |           |        |                                | 
+---+------+-----------+--------+--------------------------------+
    

FP and TLA together (16 bits) have the value 0x2002. V4ADDR is the node's global unique IPv4 address (in hexadecimal notation). SLA is the subnet identifier (65536 local subnets possible) and are usable to represent your local network structure.

For gateways, such prefix is generated by normally using SLA "0000" and suffix "::1" and assigned to the 6to4 tunnel interface.

9.1.3.2. 6to4 upstream tunneling

The node has to know to which foreign tunnel endpoint its in IPv4 packed IPv6 packets should be send to. In "early" days of 6to4 tunneling, dedicated upstream accepting routers were defined. See NSayer's 6to4 information for a list of routers.

Nowadays, 6to4 upstream routers can be found auto-magically using the anycast address 192.88.99.1. In the background routing protocols handle this, see RFC 3068 / An Anycast Prefix for 6to4 Relay Routers for details.

9.1.3.3. 6to4 downstream tunneling

The downstream (6bone -> your 6to4 enabled node) is not really fix and can vary from foreign host which originated packets were send to. There exist two possibilities:

• Foreign host uses 6to4 and sends packet direct back to your node (see below)

• Foreign host sends packets back to the world-wide IPv6 network and depending on the dynamic routing a relay router create a automatic tunnel back to your node.

9.1.3.4. Possible 6to4 traffic

• from 6to4 to 6to4: is normally directly tunneled between the both 6to4 enabled hosts

• from 6to4 to non-6to4: is sent via upstream tunneling

• non-6to4 to 6to4: is sent via downstream tunneling

9.3.1.1. Using "ip"

Common method at the moment for a small amount of tunnels.

Usage for creating a tunnel device (but it's not up afterward, also a TTL must be specified because the default value is 0).

# /sbin/ip tunnel add <device> mode sit ttl <ttldefault> remote
¬ <ipv4addressofforeigntunnel> local <ipv4addresslocal>
    

Usage (generic example for three tunnels):

# /sbin/ip tunnel add sit1 mode sit ttl <ttldefault> remote
¬ <ipv4addressofforeigntunnel1> local <ipv4addresslocal>
# /sbin/ip link set dev sit1 up
# /sbin/ip -6 route add <prefixtoroute1> dev sit1 metric 1
# /sbin/ip tunnel add sit2 mode sit ttl <ttldefault>
¬ <ipv4addressofforeigntunnel2> local <ipv4addresslocal>
# /sbin/ip link set dev sit2 up
# /sbin/ip -6 route add <prefixtoroute2> dev sit2 metric 1
# /sbin/ip tunnel add sit3 mode sit ttl <ttldefault>
¬ <ipv4addressofforeigntunnel3> local <ipv4addresslocal>
# /sbin/ip link set dev sit3 up
# /sbin/ip -6 route add <prefixtoroute3> dev sit3 metric 1
    

9.3.1.2. Using "ifconfig" and "route" (deprecated)

This not very recommended way to add a tunnel because it's a little bit strange. No problem if adding only one, but if you setup more than one, you cannot easy shutdown the first ones and leave the others running.

Usage (generic example for three tunnels):

# /sbin/ifconfig sit0 up
# /sbin/ifconfig sit0 tunnel <ipv4addressofforeigntunnel1>
# /sbin/ifconfig sit1 up
# /sbin/route -A inet6 add <prefixtoroute1> dev sit1
# /sbin/ifconfig sit0 tunnel <ipv4addressofforeigntunnel2>
# /sbin/ifconfig sit2 up
# /sbin/route -A inet6 add <prefixtoroute2> dev sit2
# /sbin/ifconfig sit0 tunnel <ipv4addressofforeigntunnel3>
# /sbin/ifconfig sit3 up
# /sbin/route -A inet6 add <prefixtoroute3> dev sit3
    

Important: DON'T USE THIS, because this setup implicit enable "automatic tunneling" from anywhere in the Internet, this is a risk, and it should not be advocated.

9.3.1.3. Using "route" only

It's also possible to setup tunnels in Non Broadcast Multiple Access (NBMA) style, it's a easy way to add many tunnels at once. But none of the tunnel can be numbered (which is a not required feature).

Usage (generic example for three tunnels):

# /sbin/ifconfig sit0 up
# /sbin/route -A inet6 add <prefixtoroute1> gw
¬ ::<ipv4addressofforeigntunnel1> dev sit0
# /sbin/route -A inet6 add <prefixtoroute2> gw
¬ ::<ipv4addressofforeigntunnel2> dev sit0
# /sbin/route -A inet6 add <prefixtoroute3> gw
¬ ::<ipv4addressofforeigntunnel3> dev sit0
    

Important: DON'T USE THIS, because this setup implicit enable "automatic tunneling" from anywhere in the Internet, this is a risk, and it should not be advocated.

9.3.2.1. Using "ip"

Usage for removing a tunnel device:

# /sbin/ip tunnel del <device>
    

Usage (generic example for three tunnels):

# /sbin/ip -6 route del <prefixtoroute1> dev sit1
# /sbin/ip link set sit1 down
# /sbin/ip tunnel del sit1
# /sbin/ip -6 route del <prefixtoroute2> dev sit2
# /sbin/ip link set sit2 down
# /sbin/ip tunnel del sit2
# /sbin/ip -6 route del <prefixtoroute3> dev sit3
# /sbin/ip link set sit3 down
# /sbin/ip tunnel del sit3
    

9.3.2.2. Using "ifconfig" and "route" (deprecated because not very funny)

Not only the creation is strange, the shutdown also...you have to remove the tunnels in backorder, means the latest created must be removed first.

Usage (generic example for three tunnels):

# /sbin/route -A inet6 del <prefixtoroute3> dev sit3
# /sbin/ifconfig sit3 down
# /sbin/route -A inet6 del <prefixtoroute2> dev sit2
# /sbin/ifconfig sit2 down
# /sbin/route -A inet6 add <prefixtoroute1> dev sit1
# /sbin/ifconfig sit1 down
# /sbin/ifconfig sit0 down
    

9.3.2.3. Using "route"

This is like removing normal IPv6 routes.

Usage (generic example for three tunnels):

# /sbin/route -A inet6 del <prefixtoroute1> gw
¬ ::<ipv4addressofforeigntunnel1> dev sit0
# /sbin/route -A inet6 del <prefixtoroute2> gw
¬ ::<ipv4addressofforeigntunnel2> dev sit0
# /sbin/route -A inet6 del <prefixtoroute3> gw
¬ ::<ipv4addressofforeigntunnel3> dev sit0
# /sbin/ifconfig sit0 down
    

9.4.1.1. Using "ip" and a dedicated tunnel device

This is now the recommended way (a TTL must be specified because the default value is 0).

Create a new tunnel device

# /sbin/ip tunnel add tun6to4 mode sit ttl <ttldefault> remote any local <localipv4address> 
    

Bring interface up

# /sbin/ip link set dev tun6to4 up 
    

Add local 6to4 address to interface (note: prefix length 16 is important!)

# /sbin/ip -6 addr add <local6to4address>/16 dev tun6to4 
    

Add (default) route to the global IPv6 network using the all-6to4-routers IPv4 anycast address

# /sbin/ip -6 route add 2000::/3 via ::192.88.99.1 dev tun6to4 metric 1
    

9.4.1.2. Using "ifconfig" and "route" and generic tunnel device "sit0" (deprecated)

This is now deprecated because using the generic tunnel device sit0 doesn't let specify filtering per device.

Bring generic tunnel interface sit0 up

# /sbin/ifconfig sit0 up 
    

Add local 6to4 address to interface

# /sbin/ifconfig sit0 add <local6to4address>/16
    

Add (default) route to the global IPv6 network using the all-6to4-relays IPv4 anycast address

# /sbin/route -A inet6 add 2000::/3 gw ::192.88.99.1 dev sit0
    

9.4.2.1. Using "ip" and a dedicated tunnel device

Remove all routes through this dedicated tunnel device

# /sbin/ip -6 route flush dev tun6to4
    

Shut down interface

# /sbin/ip link set dev tun6to4 down
    

Remove created tunnel device

# /sbin/ip tunnel del tun6to4 
    

9.4.2.2. Using "ifconfig" and "route" and generic tunnel device "sit0" (deprecated)

Remove (default) route through the 6to4 tunnel interface

# /sbin/route -A inet6 del 2000::/3 gw ::192.88.99.1 dev sit0
    

Remove local 6to4 address to interface

# /sbin/ifconfig sit0 del <local6to4address>/16
    

Shut down generic tunnel device (take care about this, perhaps it's still in use...)

# /sbin/ifconfig sit0 down 
    

11.1.1.1. Retrieving a value

The value of an entry can be retrieved using "cat":

# cat /proc/sys/net/ipv6/conf/all/forwarding
0
    

11.1.1.2. Setting a value

A new value can be set (if entry is writable) using "echo":

# echo "1" >/proc/sys/net/ipv6/conf/all/forwarding
    

11.1.2.1. Retrieving a value

The value of an entry can be retrieved now:

# sysctl net.ipv6.conf.all.forwarding
net.ipv6.conf.all.forwarding = 0
    

11.1.2.2. Setting a value

A new value can be set (if entry is writable):

# sysctl -w net.ipv6.conf.all.forwarding=1
net.ipv6.conf.all.forwarding = 1
    

Note: Don't use spaces around the "=" on setting values. Also on multiple values per line, quote them like e.g.

# sysctl -w net.ipv4.ip_local_port_range="32768 61000"
net.ipv4.ip_local_port_range = 32768 61000
    

11.1.2.3. Additionals

Note: There are sysctl versions in the wild which displaying "/" instead of the "."

For more details take a look into sysctl's manpage.

Hint: for digging fast into the settings, use the option "-a" (display all entries) in conjunction with "grep".

11.2.2.1. conf/all/forwarding

• Type: BOOLEAN

This enables global IPv6 forwarding between all interfaces.

In IPv6 you can't control forwarding per device, forwarding control has to be done using IPv6-netfilter (controlled with ip6tables) rulesets and specify input and output devices (see Firewalling/Netfilter6 for more). This is different to IPv4, where you are able to control forwarding per device (decision is made on interface where packet came in).

This also sets all interfaces' Host/Router setting 'forwarding' to the specified value. See below for details. This referred to as global forwarding.

If this value is 0, no IPv6 forwarding is enabled, packets never leave another interface, neither physical nor logical like e.g. tunnels.

11.2.3.1. accept_ra

• Type: BOOLEAN

• Functional default: enabled if local forwarding is disabled. disabled if local forwarding is enabled.

Accept Router Advertisements, and autoconfigure this interface with received data.

11.2.3.2. accept_redirects

• Type: BOOLEAN

• Functional default: enabled if local forwarding is disabled. disabled if local forwarding is enabled.

Accept Redirects sent by an IPv6 router.

11.2.3.3. autoconf

• Type: BOOLEAN

• Default: TRUE

Configure link-local addresses (see also Addresstypes) using L2 hardware addresses. E.g. this generates automagically an address like "fe80::201:23ff:fe45:6789" on an interface with a L2-MAC address.

11.2.3.4. dad_transmits

• Type: INTEGER

• Default: 1

The amount of Duplicate Address Detection probes to send.

11.2.3.5. forwarding

• Type: BOOLEAN

• Default: FALSE if global forwarding is disabled (default), otherwise TRUE

Configure interface-specific Host/Router behaviour.

Note: It is recommended to have the same setting on all interfaces; mixed router/host scenarios are rather uncommon.

• Value FALSE: By default, Host behaviour is assumed. This means:

1. IsRouter flag is not set in Neighbour Advertisements.

2. Router Solicitations are being sent when necessary.

3. If accept_ra is TRUE (default), accept Router Advertisements (and do autoconfiguration).

4. If accept_redirects is TRUE (default), accept Redirects.

• Value TRUE: If local forwarding is enabled, Router behaviour is assumed. This means exactly the reverse from the above:

1. IsRouter flag is set in Neighbour Advertisements.

2. Router Solicitations are not sent.

3. Router Advertisements are ignored.

4. Redirects are ignored.

11.2.3.6. hop_limit

• Type: INTEGER

• Default: 64

Default Hop Limit to set.

11.2.3.7. mtu

• Type: INTEGER

• Default: 1280 (IPv6 required minimum)

Default Maximum Transfer Unit

11.2.3.8. router_solicitation_delay

• Type: INTEGER

• Default: 1

Number of seconds to wait after interface is brought up before sending Router Solicitations.

11.2.3.9. router_solicitation_interval

• Type: INTEGER

• Default: 4

Number of seconds to wait between Router Solicitations.

11.2.3.10. router_solicitations

• Type: INTEGER

• Default: 3

Number of Router Solicitations to send until assuming no routers are present.

11.2.4.1. gc_thresh1

• Type: INTEGER

• Default: 128

More to be filled.

11.2.4.2. gc_thresh2

• Type: INTEGER

• Default: 512

More to be filled.

11.2.4.3. gc_thresh3

• Type: INTEGER

• Default: 1024

Tuning parameter for neighbour table size.

Increase this value if you have a lot of interfaces and problem with routes start to act mysteriously and fail. Or if a running Zebra (routing daemon) reports:

ZEBRA: netlink-listen error: No buffer space available, type=RTM_NEWROUTE(24), seq=426, pid=0
    

11.2.4.4. gc_interval

• Type: INTEGER

• Default: 30

More to be filled.

11.2.5.1. anycast_delay

• Type: INTEGER

• Default: 100

More to be filled.

11.2.5.2. gc_stale_time

• Type: INTEGER

• Default: 60

More to be filled.

11.2.5.3. proxy_qlen

• Type: INTEGER

• Default: 64

More to be filled.

11.2.5.4. unres_qlen

• Type: INTEGER

• Default: 3

More to be filled.

11.2.5.5. app_solicit

• Type: INTEGER

• Default: 0

More to be filled.

11.2.5.6. locktime

• Type: INTEGER

• Default: 0

More to be filled.

11.2.5.7. retrans_time

• Type: INTEGER

• Default: 100

More to be filled.

11.2.5.8. base_reachable_time

• Type: INTEGER

• Default: 30

More to be filled.

11.2.5.9. mcast_solicit

• Type: INTEGER

• Default: 3

More to be filled.

11.2.5.10. ucast_solicit

• Type: INTEGER

• Default: 3

More to be filled

11.2.5.11. delay_first_probe_time

• Type: INTEGER

• Default: 5

More to be filled.

11.2.5.12. proxy_delay

• Type: INTEGER

• Default: 80

More to be filled.

11.2.6.1. flush

Removed in newer kernel releases - more to be filled.

11.2.6.2. gc_interval

• Type: INTEGER

• Default: 30

More to be filled.

11.2.6.3. gc_thresh

• Type: INTEGER

• Default: 1024

More to be filled.

11.2.6.4. mtu_expires

• Type: INTEGER

• Default: 600

More to be filled.

11.2.6.5. gc_elasticity

• Type: INTEGER

• Default: 0

More to be filled.

11.2.6.6. gc_min_interval

• Type: INTEGER

• Default: 5

More to be filled.

11.2.6.7. gc_timeout

• Type: INTEGER

• Default: 60

More to be filled.

11.2.6.8. min_adv_mss

• Type: INTEGER

• Default: 12

More to be filled.

11.2.6.9. max_size

• Type: INTEGER

• Default: 4096

More to be filled.

11.3.1.1. ip_local_port_range

This control setting is used by IPv6 also.

13.2.1.1. Router advertisement

15:43:49.484751 fe80::212:34ff:fe12:3450 > ff02::1: icmp6: router
¬ advertisement(chlim=64, router_ltime=30, reachable_time=0,
¬ retrans_time=0)(prefix info: AR valid_ltime=30, preffered_ltime=20,
¬ prefix=2002:0102:0304:1::/64)(prefix info: LAR valid_ltime=2592000,
¬ preffered_ltime=604800, prefix=3ffe:ffff:0:1::/64)(src lladdr:
¬ 0:12:34:12:34:50) (len 88, hlim 255)
    

Router with link-local address "fe80::212:34ff:fe12:3450" send an advertisement to the all-node-on-link multicast address "ff02::1" containing two prefixes "2002:0102:0304:1::/64" (lifetime 30 s) and "3ffe:ffff:0:1::/64" (lifetime 2592000 s) including its own layer 2 MAC address "0:12:34:12:34:50".

13.2.1.2. Router solicitation

15:44:21.152646 fe80::212:34ff:fe12:3456 > ff02::2: icmp6: router solicitation
¬ (src lladdr: 0:12:34:12:34:56) (len 16, hlim 255)
    

Node with link-local address "fe80::212:34ff:fe12:3456" and layer 2 MAC address "0:12:34:12:34:56" is looking for a router on-link, therefore sending this solicitation to the all-router-on-link multicast address "ff02::2".

13.2.2.1. Neighbor discovery solicitation for duplicate address detection

Following packets are sent by a node with layer 2 MAC address "0:12:34:12:34:56" during autoconfiguration to check whether a potential address is already used by another node on the link sending this to the solicited-node link-local multicast address.

• Node wants to configure its link-local address "fe80::212:34ff:fe12:3456", checks for duplicate now

15:44:17.712338 :: > ff02::1:ff12:3456: icmp6: neighbor sol: who has
¬ fe80::212:34ff:fe12:3456(src lladdr: 0:12:34:12:34:56) (len 32, hlim 255)
    

• Node wants to configure its global address "2002:0102:0304:1:212:34ff:fe12:3456" (after receiving advertisement shown above), checks for duplicate now

15:44:21.905596 :: > ff02::1:ff12:3456: icmp6: neighbor sol: who has
¬ 2002:0102:0304:1:212:34ff:fe12:3456(src lladdr: 0:12:34:12:34:56) (len 32,
¬ hlim 255)
    

• Node wants to configure its global address "3ffe:ffff:0:1:212:34ff:fe12:3456" (after receiving advertisement shown above), checks for duplicate now

15:44:22.304028 :: > ff02::1:ff12:3456: icmp6: neighbor sol: who has
¬ 3ffe:ffff:0:1:212:34ff:fe12:3456(src lladdr: 0:12:34:12:34:56) (len 32, hlim
¬ 255)
    

13.2.2.2. Neighbor discovery solicitation for looking for host or gateway

• Node wants to send packages to "3ffe:ffff:0:1::10" but has no layer 2 MAC address to send packet, so send solicitation now

13:07:47.664538 2002:0102:0304:1:2e0:18ff:fe90:9205 > ff02::1:ff00:10: icmp6:
¬ neighbor sol: who has 3ffe:ffff:0:1::10(src lladdr: 0:e0:18:90:92:5) (len 32,
¬ hlim 255)
    

• Node looks for "fe80::10" now

13:11:20.870070 fe80::2e0:18ff:fe90:9205 > ff02::1:ff00:10: icmp6: neighbor
¬ sol: who has fe80::10(src lladdr: 0:e0:18:90:92:5) (len 32, hlim 255)
    

14.2.2.1. IPv6 address configuration

Edit file /etc/sysconfig/network/ifcfg-<Interface-Name> and setup following value

IP6ADDR="<ipv6-address>/<prefix>"
    

14.2.2.2. Additional information

See file /usr/share/doc/packages/sysconfig/README

14.2.3.1. IPv6 address configuration

Edit file /etc/sysconfig/network/ifcfg-<Interface-Name> and setup following value

IPADDR="<ipv6-address>/<prefix>"
    

14.2.3.2. Additional information

See file /usr/share/doc/packages/sysconfig/Network

16.3.2.1. List all IPv6 netfilter entries

• Short

# ip6tables -L 
    

• Extended

# ip6tables -n -v --line-numbers -L 
    

16.3.2.2. List specified filter

# ip6tables -n -v --line-numbers -L INPUT 
    

16.3.2.3. Insert a log rule at the input filter with options

# ip6tables --table filter --append INPUT  -j LOG --log-prefix "INPUT:"
¬ --log-level 7 
    

16.3.2.4. Insert a drop rule at the input filter

# ip6tables --table filter --append INPUT  -j DROP 
    

16.3.2.5. Delete a rule by number

# ip6tables --table filter --delete INPUT 1 
    

16.3.2.6. Allow ICMPv6

Using older kernels (unpatched kernel 2.4.5 and iptables-1.2.2) no type can be specified

• Accept incoming ICMPv6 through tunnels

# ip6tables -A INPUT -i sit+ -p icmpv6 -j ACCEPT 
    

• Allow outgoing ICMPv6 through tunnels

# ip6tables -A OUTPUT -o sit+ -p icmpv6 -j ACCEPT 
    

Newer kernels allow specifying of ICMPv6 types:

# ip6tables -A INPUT -p icmpv6 --icmpv6-type echo-request -j ACCEPT
    

16.3.2.7. Rate-limiting

Because it can happen (author already saw it to times) that an ICMPv6 storm will raise up, you should use available rate limiting for at least ICMPv6 ruleset. In addition logging rules should also get rate limiting to prevent DoS attacks against syslog and storage of log file partition. An example for a rate limited ICMPv6 looks like:

# ip6tables -A INPUT --protocol icmpv6 --icmpv6-type echo-request
¬ -j ACCEPT --match limit --limit 30/minute
    

16.3.2.8. Allow incoming SSH

Here an example is shown for a ruleset which allows incoming SSH connection from a specified IPv6 address

• Allow incoming SSH from 3ffe:ffff:100::1/128

# ip6tables -A INPUT -i sit+ -p tcp -s 3ffe:ffff:100::1/128 --sport 512:65535
¬ --dport 22 -j ACCEPT 
    

• Allow response packets (at the moment IPv6 connection tracking isn't in mainstream netfilter6 implemented)

# ip6tables -A OUTPUT -o sit+ -p tcp -d 3ffe:ffff:100::1/128 --dport 512:65535
¬ --sport 22 ! --syn j ACCEPT 
    

16.3.2.9. Enable tunneled IPv6-in-IPv4

To accept tunneled IPv6-in-IPv4 packets, you have to insert rules in your IPv4 firewall setup relating to such packets, for example

• Accept incoming IPv6-in-IPv4 on interface ppp0

# iptables -A INPUT -i ppp0 -p ipv6 -j ACCEPT 
    

• Allow outgoing IPv6-in-IPv4 to interface ppp0

# iptables -A OUTPUT -o ppp0 -p ipv6 -j ACCEPT 
    

If you have only a static tunnel, you can specify the IPv4 addresses, too, like

• Accept incoming IPv6-in-IPv4 on interface ppp0 from tunnel endpoint 1.2.3.4

# iptables -A INPUT -i ppp0 -p ipv6 -s 1.2.3.4 -j ACCEPT 
    

• Allow outgoing IPv6-in-IPv4 to interface ppp0 to tunnel endpoint 1.2.3.4

# iptables -A OUTPUT -o ppp0 -p ipv6 -d 1.2.3.4 -j ACCEPT 
    

16.3.2.10. Protection against incoming TCP connection requests

VERY RECOMMENDED! For security issues you should really insert a rule which blocks incoming TCP connection requests. Adapt "-i" option, if other interface names are in use!

• Block incoming TCP connection requests to this host

# ip6tables -I INPUT -i sit+ -p tcp --syn -j DROP 
    

• Block incoming TCP connection requests to hosts behind this router

# ip6tables -I FORWARD -i sit+ -p tcp --syn -j DROP 
    

Perhaps the rules have to be placed below others, but that is work you have to think about it. Best way is to create a script and execute rules in a specified way.

16.3.2.11. Protection against incoming UDP connection requests

ALSO RECOMMENDED! Like mentioned on my firewall information it's possible to control the ports on outgoing UDP/TCP sessions. So if all of your local IPv6 systems are using local ports e.g. from 32768 to 60999 you are able to filter UDP connections also (until connection tracking works) like:

• Block incoming UDP packets which cannot be responses of outgoing requests of this host

# ip6tables -I INPUT -i sit+ -p udp ! --dport 32768:60999 -j DROP 
    

• Block incoming UDP packets which cannot be responses of forwarded requests of hosts behind this router

# ip6tables -I FORWARD -i sit+ -p udp ! --dport 32768:60999 -j DROP 
    

20.1.1.1. Enable BIND named for listening on IPv6 address

To enable IPv6 for listening, following options are requested to change

options {
        # sure other options here, too
        listen-on-v6 { any; };
};
    

This should result after restart in e.g.

# netstat -lnptu |grep "named\W*$" 
tcp 0 0 :::53         :::*      LISTEN 1234/named
¬ # incoming TCP requests
udp 0 0 1.2.3.4:53    0.0.0.0:*        1234/named
¬ # incoming UDP requests to IPv4 1.2.3.4
udp 0 0 127.0.0.1:53  0.0.0.0:*        1234/named
¬ # incoming UDP requests to IPv4 localhost
udp 0 0 0.0.0.0:32868 0.0.0.0:*        1234/named
¬ # dynamic chosen port for outgoing queries
udp 0 0 :::53         :::*             1234/named
¬ # incoming UDP request to any IPv6
    

And a simple test looks like

# dig localhost @::1
    

and should show you a result.

20.1.1.2. Disable BIND named for listening on IPv6 address

To disable IPv6 for listening, following options are requested to change

options {
        # sure other options here, too
        listen-on-v6 { none; };
};
    

20.1.4.1. Transfer source address

Transfer source address is used for outgoing zone transfers:

transfer-source-v6 <ipv6addr|*> [port port];
    

20.1.4.2. Notify source address

Notify source address is used for outgoing notify messages:

notify-source-v6 <ipv6addr|*> [port port];
    

20.1.6.1. Current best practice

Because there are some troubles around using the new formats, current best practice is:

Forward lookup support:

• AAAA

Reverse lookup support:

• Reverse nibble format for zone ip6.int (FOR BACKWARD COMPATIBILITY)

• Reverse nibble format for zone ip6.arpa (RECOMMENDED)

20.1.7.1. IPv6 connect, but denied by ACL

Specifying a dedicated server for the query, an IPv6 connect can be forced:

$ host -t aaaa www.6bone.net 3ffe:ffff:200:f101::1 
Using domain server: 
Name: 3ffe:ffff:200:f101::1 
Address: 3ffe:ffff:200:f101::1#53 
Aliases:
Host www.6bone.net. not found: 5(REFUSED)
    

Related log entry looks like following:

Jan 3 12:43:32 gate named[12347]: client
¬ 3ffe:ffff:200:f101:212:34ff:fe12:3456#32770: 
 query denied
    

If you see such entries in the log, check whether requests from this client should be allowed and perhaps review your ACL configuration.

20.1.7.2. Successful IPv6 connect

A successful IPv6 connect looks like following:

$ host -t aaaa www.6bone.net 3ffe:ffff:200:f101::1 
Using domain server: 
Name: 3ffe:ffff:200:f101::1 
Address: 3ffe:ffff:200:f101::1#53 
Aliases:
www.6bone.net. is an alias for 6bone.net. 
6bone.net. has AAAA address 3ffe:b00:c18:1::10
    

20.3.1.1. Virtual host listen on an IPv6 address only

Listen [3ffe:ffff:100::1]:80
<VirtualHost [3ffe:ffff:100::1]:80>
        ServerName ipv6only.yourdomain.yourtopleveldomain
        # ...sure more config lines
</VirtualHost>
    

20.3.1.2. Virtual host listen on an IPv6 and on an IPv4 address

Listen [3ffe:ffff:100::2]:80 
Listen 1.2.3.4:80
<VirtualHost [3ffe:ffff:100::2]:80 1.2.3.4:80>
        ServerName ipv6andipv4.yourdomain.yourtopleveldomain
        # ...sure more config lines
</VirtualHost>
    

This should result after restart in e.g.

# netstat -lnptu |grep "httpd2\W*$" 
tcp 0 0 1.2.3.4:80          0.0.0.0:* LISTEN 12345/httpd2 
tcp 0 0 3ffe:ffff:100::1:80 :::*      LISTEN 12345/httpd2 
tcp 0 0 3ffe:ffff:100::2:80 :::*      LISTEN 12345/httpd2
    

For simple tests use the telnet example already shown.

20.3.1.3. Additional notes

• Apache2 supports a method called "sendfile" to speedup serving data. Some NIC drivers also support offline checksumming. In some cases, this can lead to connection problems and invalid TCP checksums. In this cases, disable "sendfile" either by recompiling using configure option "--without-sendfile" or by using the "EnableSendfile off" directive in configuration file.

20.4.1.1. Simple configuration

Radvd's config file is normally /etc/radvd.conf. An simple example looks like following:

interface eth0 { 
        AdvSendAdvert on;
        MinRtrAdvInterval 3; 
        MaxRtrAdvInterval 10;
        prefix 3ffe:ffff:0100:f101::/64 { 
                AdvOnLink on; 
                AdvAutonomous on; 
                AdvRouterAddr on; 
        };
};
    

This results on client side in

# ip -6 addr show eth0 
3: eth0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 100 
    inet6 3ffe:ffff:100:f101:2e0:12ff:fe34:1234/64 scope global dynamic 
       valid_lft 2591992sec preferred_lft 604792sec 
    inet6 fe80::2e0:12ff:fe34:1234/10 scope link
    

Because no lifetime was defined, a very high value was used.

20.4.1.2. Special 6to4 configuration

Version since 0.6.2pl3 support the automatic (re)-generation of the prefix depending on an IPv4 address of a specified interface. This can be used to distribute advertisements in a LAN after the 6to4 tunneling has changed. Mostly used behind a dynamic dial-on-demand Linux router. Because of the sure shorter lifetime of such prefix (after each dial-up, another prefix is valid), the lifetime configured to minimal values:

interface eth0 { 
        AdvSendAdvert on;
        MinRtrAdvInterval 3; 
        MaxRtrAdvInterval 10;
        prefix 0:0:0:f101::/64 { 
                AdvOnLink off; 
                AdvAutonomous on; 
                AdvRouterAddr on; 
                Base6to4Interface ppp0;
                AdvPreferredLifetime 20; 
                AdvValidLifetime 30;
        };
};
    

This results on client side in (assuming, ppp0 has currently 1.2.3.4 as local IPv4 address):

# ip -6 addr show eth0 
3: eth0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 100 
   inet6 2002:0102:0304:f101:2e0:12ff:fe34:1234/64 scope global dynamic 
      valid_lft 22sec preferred_lft 12sec
   inet6 fe80::2e0:12ff:fe34:1234/10 scope link
    

Because a small lifetime was defined, such prefix will be thrown away quickly, if no related advertisement was received.

20.5.3.1. Example for /etc/hosts.allow

In this file, each service which should be positive filtered (means connects are accepted) need a line.

sshd:           1.2.3. [3ffe:ffff:100:200::]/64
daytime-stream: 1.2.3. [3ffe:ffff:100:200::]/64
    

Note: there are broken implementations around, which uses following broken IPv6 network description: [3ffe:ffff:100:200::/64]. Hopefully, such versions will be fixed soon.

20.5.3.2. Example for /etc/hosts.deny

This file contains all negative filter entries and should normally deny the rest using

ALL: ALL
    

If this node is a more sensible one you can replace the standard line above with this one, but this can cause a DoS attack (load of mailer and spool directory), if too many connects were made in short time. Perhaps a logwatch is better for such issues.

ALL: ALL: spawn (echo "Attempt from %h %a to %d at `date`" 
 | tee -a /var/log/tcp.deny.log | mail root@localhost)
    

20.5.4.1. Refused connection

A refused connection via IPv4 to an xinetd covered daytime service produces a line like following example

Jan 2 20:40:44 gate xinetd-ipv6[12346]: FAIL: daytime-stream libwrap
¬ from=::ffff:1.2.3.4
Jan 2 20:32:06 gate xinetd-ipv6[12346]: FAIL: daytime-stream libwrap 
 from=3ffe:ffff:100:200::212:34ff:fe12:3456
    

A refused connection via IPv4 to an dual-listen sshd produces a line like following example

Jan 2 20:24:17 gate sshd[12345]: refused connect from ::ffff:1.2.3.4
¬ (::ffff:1.2.3.4)
Jan 2 20:39:33 gate sshd[12345]: refused connect 
 from 3ffe:ffff:100:200::212:34ff:fe12:3456
¬ (3ffe:ffff:100:200::212:34ff:fe12:3456)
    

20.5.4.2. Permitted connection

A permitted connection via IPv4 to an xinetd covered daytime service produces a line like following example

Jan 2 20:37:50 gate xinetd-ipv6[12346]: START: daytime-stream pid=0
¬ from=::ffff:1.2.3.4 
Jan 2 20:37:56 gate xinetd-ipv6[12346]: START: daytime-stream pid=0 
 from=3ffe:ffff:100:200::212:34ff:fe12:3456
    

A permitted connection via IPv4 to an dual-listen sshd produces a line like following example

Jan 2 20:43:10 gate sshd[21975]: Accepted password for user from ::ffff:1.2.3.4
¬ port 33381 ssh2
Jan 2 20:42:19 gate sshd[12345]: Accepted password for user 
 from 3ffe:ffff:100:200::212:34ff:fe12:3456 port 33380 ssh2
    

23.1.1.1. Cisco

• Cisco Self-Study: Implementing IPv6 Networks (IPV6), by Regis Desmeules. Cisco Press; ISBN 1587050862; 500 pages; 1st edition (April 11, 2003). Note: This item will be published on April 11, 2003.

• Configuring IPv6 with Cisco IOS, by Sam Brown, Sam Browne, Neal Chen, Robbie Harrell, Edgar, Jr. Parenti (Editor), Eric Knipp (Editor), Paul Fong (Editor)362 pages; Syngress Media Inc; ISBN 1928994849; (July 12, 2002).

23.1.1.2. General

• IPv6 Essentials by Silvia Hagen, July 2002, O'Reilly Order Number: 1258, ISBN 0-5960-0125-8, 352 pages. ToC, Index, Sample Chapter etc.; O'Reilly Pressrelease

• IPv6: The New Internet Protocol. By Christian Huitema; Published by Prentice-Hall; ISBN 0138505055. Description: This book, written by Christian Huitema - a member of the InternetArchitecture Board, gives an excellent description of IPv6, how it differs from IPv4, and the hows and whys of it's development. Source: http://www.cs.uu.nl/wais/html/na-dir/internet/tcp-ip/resource-list.html

• IPv6 Networks by Niles, Kitty; (ISBN 0070248079); 550 pages; Date Published 05/01/1998.

• Implementing IPV6. Supporting the Next Generation Internet Protocols by P. E. Miller, Mark A. Miller; Publisher: John Wiley & Sons; ISBN 0764545892; 2nd edition (March 15, 2000); 402 pages.

• Big Book of Ipv6 Addressing Rfcs by Peter H. Salus (Compiler), Morgan Kaufmann Publishers, April 2000, 450 pages ISBN 0126167702.

• Understanding IPV6 by Davies, Joseph; ISBN 0735612455; Date Published 05/01/2001; Number of Pages: 350. Understanding IPV6 by Davies, Joseph; ISBN 0735612455; Date Published 13/11/2002; Number of Pages 544.

• Migrating to IPv6 - IPv6 in Practice. By Marc Blanchet Publisher: John Wiley & Sons; ISBN 0471498920; 1st edition (November 2002); 368 pages.

• Programming IPv6 by Sean Walton; 560 pages; Addison-Wesley Professional; ISBN 0672323443 Note: Will be published August 1, 2003.

• Wireless boosting IPv6 by Carolyn Duffy Marsan, 10/23/2000.

• O'reilly Network search for keyword IPv6 results in 29 hits (28. January 2002).

23.3.1.1. Global registries

• IPv6 test backbone: 6bone, How to join 6bone, Teilnahme am 6bone (german language), 6bone participation (english language)

23.3.1.2. Major regional registries

• America: ARIN, ARIN / registration page, ARIN / IPv6 guidelines

• EMEA: Ripe NCC, Ripe NCC / registration page, Ripe NCC / IPv6 registration

• Asia/Pacific: APNIC, APNIC / IPv6 ressource guide

• Latin America and Caribbea: LACNIC, IPv6 Registration Services, IPv6 Allocation Policy

• Africa: AfriNIC

Also a list of major (prefix length 35) allocations per local registry is available here: Ripe NCC / IPv6 allocations.

23.3.1.3. Tunnel brokers

Note: A list of available Tunnel broker can be found in the section Tunnel broker below.

• Sourcecode used in Vermicellis Master thesis about tunnelbroker, University of Tromso.

• Former IPng. Tunnelbroker and IPv6 resources, now migrated to the SixXs System.

• Eckes' IPv6-with-Linux Page.

• RIPE6.net: Configure an IPv6 Tunnel to a tunnelbroker; Route ipv6-ips from your router to other clients in your network...

• tunnelc - a perl based tunnel client script: freshmeat.net: Project details for tunnel client SourceForge: Project Info - tunnelc (also here)

• Tunnelbroker Maillingliste

• Linux Advanced Routing & Traffic Control HOWTO, Chapter 6: IPv6 tunneling with Cisco and/or 6bone.

See also here for more information and URLs: ipv6-net.org.

23.3.1.4. 6to4

• NSayer's 6to4 information

• RFC 3068 / An Anycast Prefix for 6to4 Relay Routers

23.3.1.5. ISATAP

• ISATAP (Intra-Site Automatic Tunnel Access Protocol) Information by JOIN

23.3.3.1. IPv6-related Request For Comments (RFCs)

Publishing the list of IPv6-related RFCs is beyond the scope of this document, but given URLs will lead you to such lists:

• List sorted by IPng Standardization Status or IPng Current Specifications by Robert Hinden

• IPv6 Related Specifications on IPv6.org

23.3.3.2. Current drafts of working groups

Current (also) IPv6-related drafts can be found here:

• IP Version 6 (ipv6)

• Next Generation Transition (ngtrans)

• Dynamic Host Configuration (dhc)

• Domain Name System Extension (dnsext)

• Mobile IP (mobileip)

• Get any information about IPv6, from overviews, through RFCs & drafts, to implementations (including availability of stacks on various platforms & source code for IPv6 stacks)

• IPv6 specifications - Latest RFCs and Internet Drafts Collection.

23.3.3.3. Others

• Network Sorcery / IPv6, Internet Protocol version 6, IPv6 protocol header

• SWITCH IPv6 Pilot / References, big list of IPv6 references maintained by Simon Leinen

• Advanced Network Management Laboratory / IPv6 Address Oracle shows you IPv6 addresses in detail

23.3.4.1. Linux related

• DeepSpace6 / (Not only) Linux IPv6 Portal - Italy (Mirror)

• IPv6-HowTo for Linux by Peter Bieringer - Germany, and his Bieringer / IPv6 - software archive

• Linux+IPv6 status by Peter Bieringer - Germany (going obsolete)

• DeepSpace6 / IPv6 Status Page - Italy (Mirror) (will superseed upper one)

• USAGI project - Japan, and their USAGI project - software archive

• Gav's Linux IPv6 Page

23.3.4.2. Linux related per distribution

For more see the IPv6+Linux Status Distributions page.

23.3.4.3. General

• IPv6.org

• 6bone

• UK IPv6 Resource Centre - UK

• JOIN: IPv6 information - Germany, by the JOIN project team maintaining also Links to external WWW pages comprising IPv6/IPng.

• TIPSTER6 project - Hungary, "Testing Experimental IPv6 Technology and Services in Hungary".

• WIDE project - Japan

• SWITCH IPv6 Pilot - Switzerland

• IPv6 Corner of Hubert Feyrer - Germany

• Vermicelli Project - Norway

• IPv6 Forum - a world-wide consortium of leading Internet vendors, Research & Education Networks...

• Playground.sun.com / IPv6 Info Page - maintained by Robert Hinden, Nokia. Get any information about IPv6, from overviews, through RFCs & drafts, to implementations (including availability of stacks on various platforms & source code for IPv6 stacks).

• NASA Ames Research Center (old content)

• 6INIT - IPv6 Internet Initiative - an EU Fifth Framework Project under the IST Programme.

• IPv6 Task Force (European Union)

• IPv6 Document Project (Japanese language)

• 6init - IPv6 INternet IniTiative

• IP Next Generation Overview

• The IPng Group's home page.

• IPv6: The New Version of the Internet Protocol, by Steve Deering.

• IPv6: The Next Generation Internet Protocol, by Gary C. Kessler.

• IPv6: Next Generation Internet Protocol - 3Com

• Literature Research IPv6 (IPng), by Mike Crawfurd.

• Next Generation Internet Initiative

• internet || site and internet2 Working Group - Presentation (HTML + PPT) from IPv6 Workshops: (Stateless Autoconfiguration, IPv6 Addressing, USAGI, Provider Independent IPv6 Addressing and other topics).

• NetworkWorldFusion: Search / Doc Finder: searched for IPv6 (102 documents found 22.12.2002)

• The Register (Search for IPv6 will result in 30 documents, 22.12.2002)

• ZDNet Search for IPv6

• TechTarget Search for IPv6

• IPv6 & TCP Resources List

• Klingon IPv6 tools, Klingon IPv6 tools (native IPv6 only access): IPv6 firewall examples, bandwith testing and portscanner

Something missing? Suggestions are welcome!

23.3.4.4. Market Research

• A Tale of Two Wireless Technology Trends: Processor Development Outsourcing and IPv6Yankee Group - 4/1/2002 - 12 Pages - ID: YANL768881

• The World Atlas of the Internet: Americas; IDATE - 2/1/2002 - 242 PAges - ID: IDT803907. Countries covered: Central America, North America, South America; List: Price: $ 3,500.00; excerpt: Panorama of Internet access markets across the globe. Market assessment and forecasts up to 2006 for 34 countries: market structure: main ISPs and market shares; number of subscribers, of ISPs.

• Early Interest Rising for IPv6 by IDC (Author); List Price: $1,500.00; Edition: e-book (Acrobat Reader); Publisher: IDC; ISBN B000065T8E; (March 1, 2002)

23.3.4.5. Patents

• Canadian Patent Database: Home, Search (Basic Search, just enter IPv6 in the search field ;-); 84 documents found 22.12.2002)

• Espacenet - European patent information: National Offices, Members of Espacenet(IPv6: 84 documents, 22.12.2002)

• Delphion Research: Patent Search Page. Basic (free) registration needed. Examples found 21.12.2002 searching for IPv6: Communicating method between IPv4 terminal and IPv6 terminal and IPv4-IPv6 converting apparatus Translator for IP networks, network system using the translator, and IP network coupling method therefor

23.3.5.1. Europe

• www.ist-ipv6.org: IST IPv6 Cluster, European IPv6 Research and Development Projects

• Euro6IX: European IPv6 Internet Exchanges Backbone

23.3.5.2. Austria

• IPv6@IKNnet and MIPv6 Research Group: TU Vienna, Austria (IPv6: project, publications, diploma / doctor thesis, Conference Proceedings etc.)

23.3.5.3. Australia

• Carl's Australian IPv6 Pages (old content)

23.3.5.4. Belgium

• BELNET: the Belgian Research Network

• Euronet: one of the biggest ISP's of Belgium...

23.3.5.5. Brasilia

• BR6bone

23.3.5.6. China

• Nokia China - IPv6 Site

• Internet6 Initiative by Nokia China

23.3.5.7. Czech

• IPv6 in Czech On Line

23.3.5.8. Germany

• IPv6-net.org: German IPv6 forum

23.3.5.9. France

• Renater: Renater IPv6 Project Page

• IPv6 - RSVP - ATM at INRIA

• NetBSD IPv6 Documentation

23.3.5.10. Hungary

• Testing Experimental IPv6 Technology and Services in Hungary

• Hungarian IPv6 Information Page

23.3.5.11. India

• IPv6 at BITS

23.3.5.12. Italy

• Project6: IPv6 networking with Linux

• Edisontel: IPv6 Portal of Edisontel

23.3.5.13. Japan

• Linux IPv6 Users Group JP

• Yamaha IPv6 (sorry, all in japanese native ...)

23.3.5.14. Korea

• ETRI: Electronics and Telecommunications Research Institut

• IPv6 Forum Korea: Korean IPv6 Deployment Project

23.3.5.15. Mexico

• IPv6 Mexico (spain & english version): IPv6 Project Hompeage of The National Autonomous University of Mexico (UNAM)

23.3.5.16. Netherland

• SURFnet: SURFnet IPv6 Backbone

• STACK, STACK (IPv6): Students' computer association of the Eindhoven University of Technology, Netherland

• IPng.nl: collaboration between WiseGuys and Intouch

23.3.5.17. Portugal

• IPv6 pages of Miguel Rosa (broken?)

• FCCN (National Foundation for the Scientific Computation)

• University of Algarve, Portugal

• IPv6 - MFA

23.3.5.18. Russia

• IPv6 Forum for Russia: Yaroslavl State University Internet Center

23.3.5.19. Switzerland

• SWITCH: The Swiss Education & Research Network

23.3.5.20. United Kingdom

• IPv6 in the UK

• UK IPv6 Resource Center

• British Telecom IPv6 Home: BT's ISP IPv6 Trial, UK's first IPv6 Internet Exchange etc.

23.3.6.1. *BSD

• KAME project (*BSD)

• NetBSD's IPv6 Networking FAQ

• FreeBSD Documentation Project

• FreeBSD Ports: Ipv6

• BUGAT - BSD Usergroup Austria - www.bugat.at: FreeBSD IPv6 Tunnel (German language)

23.3.6.2. Cisco IOS

• Cisco IOS IPv6 Entry Page

• IPv6 for Cisco IOS Software, File 2 of 3: Aug 2002 -- Table of Contents: IPv6 for Cisco IOS Software; Configuring Documentation Specifics; Enabling IPv6 Routing and Configuring; IPv6 Addressing; Enabling IPv6 Processing Globally.

• Cisco Internet Networking Handbook, Chapter IPv6

23.3.6.3. Compaq

• IPv6 at Compaq - Presentations, White Papers, Documentation...

23.3.6.4. HPUX

• comp.sys.hp.hpux FAQ

23.3.6.5. IBM

• Now that IBM's announced the availability of z/OS V1.4, what's new in this release? This question was posed on 15 August 2002

23.3.6.6. Microsoft

• Microsoft Windows 2000 IPv6

• MSRIPv6 - Microsoft Research Network - IPv6 Homepage

• Getting Started with the Microsoft IPv6 Technology Preview for Windows 2000

• Internet Connection Firewall Does Not Block Internet Protocol Version 6 Traffic (6.11.2001)

• Internet Protocol Numbers (8.10.2002)

• IPv6 Technology Preview Refresh (16.10.2002)

• HOW TO: Install and Configure IP Version 6 in Windows .NET Enterprise Server (26.10.2002)

• Windows .NET Server 6to4 Router Service Quits When You Advertise a 2002 Address on the Public Interface (28.10.2002)

• msdn - Microsoft Windows CE .NET - IPv6 commands

• msdn - search for IPv6 (100 results, 22.12.2002)

23.3.6.7. Solaris

• Sun Microsystems IPv6 Page for Solaris 8

• Solaris 2 Frequently Asked Questions (FAQ) 1.73

23.3.6.8. Sumitoma

• Sumitomo Electric has implemented IPv6 on Suminet 3700 family routers

23.3.6.9. ZebOS

• IpInfusion's ZebOS Server Routing Software

23.3.8.1. Analyzer tools

• Ethereal - Ethereal is a free network protocol analyzer for Unix and Windows

• Radcom RC100-WL - Download Radcom RC100-WL protocol analyzer version 3.20

23.3.8.2. IPv6 Products

• 6wind - solutions for IPv4/IPv6 Router, QoS, Multicast, Mobility, Security/VPN/Firewall.

• Fefe's patches for IPv6 with djbdnsAug 2002 -- What is djbdns and why does it need IPv6? djbdns is a full blown DNS server which outperforms BIND in nearly all respects.

• Hitachi, Ltd. IPv6 Home PageIPv6 Products GR2000 - IPv6 router; Toolnet6 - Protocol Exchange software for IPv6.

• ZebOS Server Routing Suite

• SPA Mail Server 2.21

• Inframail (Advantage Server Edition) 4.0

• HTTrack Website Copier 3.2

• CommView 3.4

• Posadis 0.50.6

• Xceed Winsock Library 1.2

• CommView 3.4

• TCP Wrapper (IPv6 aware)

23.3.8.3. SNMP

• comp.protocpols.snmp SNMP FAQ Part 1 of 2

23.4.2.1. Estonia

• TIX (tallinn interneti exchange with ipv6 support)

23.4.2.2. Europe

• Euro6IX, European IPv6 Internet Exchange Backbone

23.4.2.3. France

• French National Internet Exchange IPv6 (since 1.11.2002 active). FNIX6 provides a free and reliable high speed FastEthernet interconnection between ISP located in TeleCity Paris.

23.4.2.4. Germany

• INXS: (Cable & Wireless) Munich and Hamburg

23.4.2.5. Japan

• NSPIXP-6: IPv6-based Internet Exchange in Tokyo

• JPIX, Tokyo

23.4.2.6. Korea

• 6NGIX

23.4.2.7. Netherlands

• AMS-IX: Amsterdam Internet Exchange

23.4.2.8. UK

• UK6X: London

• XchangePoint: London

23.4.2.9. USA

• 6TAP: Chicago. Supports peerings around the globe.

• NY6IX: New York City IPv6 based Internet Exchange

• 6IIX: New York, Los Angeles and Santa Clara

• PAIX: Palo Alto

23.4.3.1. Belgium

• Wanadoo

23.4.3.2. Canada

• Freenet6 - /48 Delegation, Canada Getting IPv6 Using Freenet6 on Debian Freenet6 creater

23.4.3.3. China

• CERNET-Nokia

23.4.3.4. Estonia

• Estpak

23.4.3.5. Europe

• XS26 Distributed Tunnel Broker, USA & Europe

23.4.3.6. Germany

• JOIN, University of Münster

• Tunnelbroker Leipzig, Germany - DialupUsers with dynamic IP's can get a fix IPv6 IP... JOIN, Tunnelbroker Leipzig, (currently offline ?) Das offizielle IPv6 Forum, Leipziger Tunnelbroker Experimental Live IPv6 Stream! 6bone Knoten Leipzig Info bez. Hackangriff (2001) Tunnelbroker for JOIN. This tunnel broker is only available for students and staff members of colleges and universities

• Berkom

23.4.3.7. Italy

• Centro Studi e Laboratory Telecomunicazioni ( Downloadpage: TunnelBroker Version 2.1.) IPv6 Tunnel Broker: Installation instructions

• EdisonTel

• Comv6

• Bersafe (Italian language)

• Telecom Italia LAB (Tunnelbroker Software Downloadpage)

23.4.3.8. Japan

• Internet Initiative Japan (Japanese language) - with IPv6 native line service and IPv6 tunneling Service

23.4.3.9. Malaysia

• Manis

23.4.3.10. Netherlands

• XS26 - "Access to Six" - with POPs in Slovak Republic, Czech Republic, Netherlands, Germany and Hungary.

• IPng Netherland - Intouch, SurfNet, AMS-IX, UUNet, Cistron, RIPE NCC and AT&T are connected at the AMS-IX. It is possible (there are requirements...) to get an static tunnel.

• SURFnet Customers

23.4.3.11. Norway

• UNINETT, Norway - Pilot IPv6 Service (for Customers): tunnelbroker & address allocation UNINETT's Tunnel Broker (link correct, but inavailable - 23.12.2002) Uninett-Autoupdate-HOWTO

23.4.3.12. Switzerland

• Tunnelbroker AS8758, Dolphins Network Systems (since 20.12.2002 online)

23.4.3.13. UK

• NTT Europe, NTT, United Kingdom - IPv6 Trial. IPv4 Tunnel and native IPv6 leased Line connections. POPs are located in London, UK Dusseldorf, Germany New Jersey, USA (East Coast) Cupertino, USA (West Coast) Tokyo, Japan

• BtexacT IPv6 Tunnel Broker Service

• IPNG-UK

23.4.3.14. USA

• ESnet, USA - Energy Sciences Network: Tunnel Registry & Address Delegation for directly connected ESnet sites and ESnet collaborators.

• 6REN, USA - The 6ren initiative is being coordinated by the Energy Sciences Network (ESnet), the network for the Energy Research program of the US Dept. of Energy, located at the University of California's Lawrence Berkeley National Laboratory.

• XS26 Distributed Tunnel Broker, USA & Europe

• Hurricane Electric, US backbone; Hurrican Electric Tunnelbroker (also available under http://tunnelbroker.com/) Press Release: Hurricane Electric Upgrades IPv6 Tunnel Broker Tunnel Broker Endpoint Autoupdate, Perl Script

• Mondo Services

• DHIS Dynamic Tunnel, Dynamic Host Information System, University of Bradford

23.4.3.15. More Tunnel brokers...

• Public 6to4 relay routers (MS IIE boycott!)

23.4.4.1. Game Server

• Quake2 over IPv6

23.4.4.2. IRC Server

• Cyconet (Cyconet IRCnet Servers over IPv6)

23.4.4.3. Radio Stations, Music Streams

• Experimental Live IPv6 Stream!, University of Leipzig, Germany

23.4.4.4. Webserver

• Peter Bieringer's Home of Linux IPv6 HOWTO

Something missing? Suggestions are welcome!

24.2.2.1. Document technique related

Writing a LDP HOWTO as a newbie (in LyX and exporting this to DocBook to conform to SGML) isn't as easy as some people say. There are some strange pitfalls... Nevertheless, thanks to:

• Authors of the LDP Author Guide

• B. Guillon: For his DocBook with LyX HOWTO

24.2.2.2. Content related credits

Credits for fixes and hints are listed here, will grow sure in the future

• S .P. Meenakshi <meena at cs dot iitm dot ernet dot in>: For a hint using a "send mail" shell program on tcp_wrapper/hosts.deny

• Frank Dinies <FrankDinies at web dot de>: For a bugfix on IPv6 address explanation

• John Freed <jfreed at linux-mag dot com>: For finding a bug in IPv6 multicast address explanation

• Craig Rodrigues <crodrigu at bbn dot com>: For suggestion about RHL IPv6 setup

• Fyodor <fyodor at insecure dot org>: Note me about outdated nmap information

• Mauro Tortonesi <mauro at deepspace6 dot net>: For some suggestions

• Tom Goodale <goodale at aei-potsdam dot mpg dot de>: For some suggestions

• Martin Luemkemann <mluemkem at techfak dot uni-bielefeld dot de>: For a suggestion

• Jean-Marc V. Liotier <jim at jipo dot com>: Finding a bug

• Yaniv Kaul <ykaul at checkpoint dot com>: Finding a bug

• Arnout Engelen <arnouten at bzzt dot net>: For sending note about a draft was adopted to RFC now

• Stephane Bortzmeyer <bortzmeyer at nic dot fr>: Contributing persistent configuration on Debian

• lithis von saturnsys <lithis at saturnsys dot com>: Reporting a misaddressed URL

• Guy Hulbert <gwhulbert at rogers dot com>: Send a note that RFC1924 is probably an April fool's joke

• Tero Pelander <tpeland at tkukoulu dot fi>: Reporting a broken URL

• Walter Jontofsohn <wjontof at gmx dot de>: Hints for SuSE Linux 8.0/8.1

• Benjamin Hofstetter <benjamin dot hofstetter at netlabs dot org>: Reporting a mispointing URL

• J.P. Larocque <piranha at ely dot ath dot cx>: Reporting archive URL for maillist users at ipv6 dot org

• Jorrit Kronjee <jorrit at wafel dot org>: Reporting broken URLs

• Colm MacCarthaigh <colm dot maccarthaigh at heanet dot ie>: Hint for sendfile issue on Apache2

• Tiago Camilo <tandre at ipg dot pt>: Contribute some URLs about Mobile IPv6

• Harald Geiger: Reporting a bug in how described the bit counting of the universal/global bit

• Bjoern Jacke <bjoern at j3e dot de>: Triggered me to fix some outdated information on xinetd