IPv6: Guests only reachable for a (very) short time after reboot

[shake]

Hi guys,

I am currently trying to solve an issue related to IPv6.
I am following the tutorial that can be found at http://wiki.hetzner.de/index.php/Proxmox_VE/en

IPv4 works as expected, but IPv6 is problematic.
When rebooting the host and starting my VMs immediately, IPv6 works as expected.

But after some time of inactivity (no ipv6 ping running) they lose the connection.


ip -6 neigh on the host:
Contains no signs of the guest addresses anymore

ip -6 on the guest:
2a01:4f8:160:104a::2 dev eth0 FAILED
fe80::48f6:f0ff:fe01:de65 dev eth0 FAILED
fe80::9:b3ff:fe89:6753 dev eth0 lladdr 3a:0e:4e:0e:4d:48 router STALE


(first line: host address
second line: no idea, nothing to see in any of my guests, nor the host
third line: host: vmbr0
)


Any idea what might be happening?



pveversion:
pve-manager/3.4-1/3f2d890e (running kernel: 2.6.32-37-pve)

 

[shake]

/etc/network/interfaces on host:

# Loopback device:
auto lo
iface lo inet loopback


# device: eth0
auto eth0
iface eth0 inet static
address 176.9.136.81
netmask 255.255.255.255
gateway 176.9.136.65
pointopoint 176.9.136.65


iface eth0 inet6 static
address 2a01:4f8:160:104a::2
netmask 128
gateway fe80::1
up sysctl -p


auto vmbr0
iface vmbr0 inet static
address 176.9.138.81
netmask 255.255.255.255
bridge_ports none
bridge_stp off
bridge_fd 0
up ip route add 176.9.159.237/32 dev vmbr0
up ip route add 176.9.159.236/32 dev vmbr0
up ip route add 5.9.220.94/32 dev vmbr0


iface vmbr0 inet6 static
address 2a01:4f8:160:104a::2
netmask 64

 

[shake]

/etc/network/interfaces on guest (Ubuntu 14.04.2)


auto lo
iface lo inet loopback
iface lo inet6 loopback


# The primary network interface
auto eth0
iface eth0 inet static
address 176.9.159.237
netmask 255.255.255.255
gateway 176.9.136.81
pointopoint 176.9.136.81
dns-nameservers 8.8.8.8


iface eth0 inet6 static
address 2a01:4f8:160:104a::202
netmask 64
gateway 2a01:4f8:160:104a::2
dns-namesevers 2a01:4f8:0:a0a1::add:1010 2a01:4f8:0:a102::add:9999 2a01:4f8:0:a111::add:9898

 

[shake]

What works:

Pinging the local address of the host from guest works after an initial delay of 1 or 2 seconds.
Then "ip -6 neigh" (on the host) shows the fe80: address as REACHABLE


Host:
ip -6 route

2a01:4f8:160:104a::2 dev eth0 proto kernel metric 256 mtu 1500 advmss 1440 hoplimit 0
2a01:4f8:160:104a::/64 dev vmbr0 proto kernel metric 256 mtu 1500 advmss 1440 hoplimit 0
fe80::1 dev venet0 proto kernel metric 256 mtu 1500 advmss 1440 hoplimit 0
fe80::/64 dev eth0 proto kernel metric 256 mtu 1500 advmss 1440 hoplimit 0
fe80::/64 dev vmbr0 proto kernel metric 256 mtu 1500 advmss 1440 hoplimit 0
fe80::/64 dev venet0 proto kernel metric 256 mtu 1500 advmss 1440 hoplimit 0
fe80::/64 dev tap201i0 proto kernel metric 256 mtu 1500 advmss 1440 hoplimit 0
fe80::/64 dev tap202i0 proto kernel metric 256 mtu 1500 advmss 1440 hoplimit 0
default via fe80::1 dev eth0 metric 1024 mtu 1500 advmss 1440 hoplimit 0




Guest
ip -6 route

2a01:4f8:160:104a::/64 dev eth0 proto kernel metric 256
fe80::/64 dev eth0 proto kernel metric 256
default via 2a01:4f8:160:104a::2 dev eth0 metric 1024

 

[shake]

I tried it with an older kernel: pve-manager/3.4-1/3f2d890e (running kernel: 2.6.32-26-pve)

And it seems to work with this one!
So maybe a regression?

 

[morganh]

Dear,

I've the same problem, with an old kernel (2.6.32-34-pve) the IPv6 work fine but not work if I use the lasted kernel (2.6.32-37-pve).
The IPv6 bot work on host and on guests.

/etc/network/interfaces

iface vmbr0 inet6 static address 2001:41D0:xxxx:xxxx::1
netmask 64
post-up /sbin/ip -f inet6 route add 2001:41D0:xxxx:xxff:ff:ff:ff:ff dev vmbr0
post-up /sbin/ip -f inet6 route add default via 2001:41D0:xxxx:xxff:ff:ff:ff:ff
post-up sysctl -p /etc/sysctl.conf
pre-down /sbin/ip -f inet6 route del default via 2001:41D0:xxxx:xxff:ff:ff:ff:ff
pre-down /sbin/ip -f inet6 route del 2001:41D0:xxxx:xxff:ff:ff:ff:ff dev vmbr0

/etc/sysctl.conf

net.ipv6.conf.all.forwarding = 1
net.ipv6.conf.default.forwarding = 1
net.ipv6.conf.all.autoconf = 0
net.ipv6.conf.default.autoconf = 0
net.ipv6.conf.vmbr0.autoconf = 0
net.ipv6.conf.all.accept_ra = 0
net.ipv6.conf.default.accept_ra = 0
net.ipv6.conf.vmbr0.accept_ra = 0
net.ipv6.conf.vmbr0.accept_ra = 0
net.ipv6.conf.vmbr0.autoconf = 0
net.ipv6.conf.default.proxy_ndp = 1
net.ipv6.conf.all.proxy_ndp = 1

Thanks for your help

 

[lopar]

Same issue there : http://forum.proxmox.com/threads/21048-IPv6-bridging-issue-with-latest-pve-kernel-3-10-0-7-pve (misplaced thread, my bad!)