IPV6 forwarding problem

[chupnik]

After several attempts, decided to ask a question in the forum.
Intuition tells me that this is due PVE specific scripts

I can't set up IPV6 forwarding is not one of those ways?
1.

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

2.

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

3.

echo "net.ipv6.conf.all.forwarding=1" > /etc/sysctl.conf

After reboot host machine i get this:

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

IPV6 forwarding working if i set up it manuall through

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

But it works only before reboot.

 

[mo_]

3.

echo "net.ipv6.conf.all.forwarding=1" > /etc/sysctl.conf

In case that this is not a typo: remember that using ">" will overwrite the whole file and put that one line as the only one into it, which clearly isnt what youd want

 

[chupnik]

Yes, it's my typo. My sysctl.conf file already has a net.ipv6.conf.all.forwarding=1
But it turns off after reboot.
I also tried to add it to post-up in eth0 section, but without success.

 

[mo_]

are you missing "net.ipv6.conf.all.autoconf=0"
in /etc/sysctl.conf by any chance?

 

[chupnik]

In my sysctl.conf it's sets to zero(0).
I think I found the solution
http://strugglers.net/~andy/blog/2011/09/04/linux-ipv6-router-advertisements-and-forwarding/

It looks like you're talking about, though I do not quite understand the value of this setting.

 

[chupnik]

are you missing "net.ipv6.conf.all.autoconf=0"
in /etc/sysctl.conf by any chance?

It's set to 0. the way it should be?
I seem to have found a solution http://strugglers.net/~andy/blog/2011/09/04/linux-ipv6-router-advertisements-and-forwarding/
It looks like you said that's about it.
I will test this solution. Although not really understand the value of this parameter.

 

[chupnik]

I have autoconf turned off.
A similar problem is described in this article, but I do not really understand the relationship between these settings. I have IP6 statically configured.
http://strugglers.net/~andy/blog/2011/09/04/linux-ipv6-router-advertisements-and-forwarding/

 

[mo_]

hes describing something you dont really need. what you do need however is accept_ra to be 0. heres how the complete sysctl.conf of one of my ipv6-enabled nodes looks like:

net.ipv6.conf.all.proxy_ndp=1
net.ipv6.conf.default.autoconf=0
net.ipv6.conf.default.accept_ra=0
net.ipv6.conf.default.accept_ra_defrtr=0
net.ipv6.conf.default.accept_ra_rtr_pref=0
net.ipv6.conf.default.accept_ra_pinfo=0
net.ipv6.conf.default.accept_source_route=0
net.ipv6.conf.default.accept_redirects=0
net.ipv6.conf.default.forwarding=1
net.ipv6.conf.all.autoconf=0
net.ipv6.conf.all.accept_ra=0
net.ipv6.conf.all.accept_ra_defrtr=0
net.ipv6.conf.all.accept_ra_rtr_pref=0
net.ipv6.conf.all.accept_ra_pinfo=0
net.ipv6.conf.all.accept_source_route=0
net.ipv6.conf.all.accept_redirects=0
net.ipv6.conf.all.forwarding=1

 

[chupnik]

I've copied all the above parameters, but no luck.
Apparently there is some dependence of the parameters of each other.

 

[mo_]

Well the above works for me and I'm at a loss of ideas why it wouldn't do the same for you (unless theres something like NetworkManager on your server, which would mess up pretty much everything).

 

[chupnik]

This issue is related to features of the kernel used with Proxmox VE 3.0 and boot process.
This link described solution more detail http://blog.endpoint.com/2013/07/proxmox-and-fun-maze-of-ipv6.html

 

[chupnik]

This line

up sysctl -p # <------ ADDED THIS LINE TO FIX IPv6 CONNECTIVITY ISSUES

in inet6 section of /etc/network/interfaces fix this problem.

All ipv6 related settings from /etc/sysctl.conf works after reboot!

For example

iface eth0 inet6 static
address    YOUR:IPV6:IS:HERE
netmask    64
up ip -6 route add default via fe80::1 dev eth0
up sysctl -p # <------ ADDED THIS LINE TO FIX IPv6 CONNECTIVITY ISSUES

 

[tom]

Reason is that the ipv6 module is not loaded by default in the 2.6.32 kernel (3.10 loads this automatically).


you need to add the ipv6 module in /etc/modules
___
# /etc/modules: kernel modules to load at boot time.
#
# This file contains the names of kernel modules that should be loaded
# at boot time, one per line. Lines beginning with "#" are ignored.
# Parameters can be specified after the module name.
ipv6
__

then all ipv6 setting in /etc/sysctl.conf works

 

[chupnik]

Reason is that the ipv6 module is not loaded by default in the 2.6.32 kernel (3.10 loads this automatically).

But I managed to enable IPV6 forwarding in /etc/sysctl.conf using this code in /etc/network/interfaces:

iface eth0 inet6 static
  address xxxx:xxxx:xxxx:xxxx::2
  netmask 128
  gateway xxxx:xxxx:xxxx:xxxx::1
  up sysctl -p

The last line makes all the magic