[SOLVED] ifupdown2 mess with IPv6 global

[lixaotec]

Dear folks,

I recently updated my 6.2-4 pve to the latest packages on no-subscription repo that became 6.2-15.

Right after I did installed ifupdown2 in order to acomplish network changes without reboot.

Therefore I notice that after it, my pve host ipv6 (that is assigned auto by slaac) stopped working. The global Ipv6 doesnt assign anymore. I tried reboot and nothing.

I have not changed any config other than installing ifupdown2.

Has anyone been thought that before?

How may I troubleshoot?

Thanks

 

[spirit]

Can you send the content or /etc/network/interfaces ?

 

[lixaotec]

Sure @spirit

Thanks in advance

# network interface settings; autogenerated
# Please do NOT modify this file directly, unless you know what
# you're doing.
#
# If you want to manage parts of the network configuration manually,
# please utilize the 'source' or 'source-directory' directives to do
# so.
# PVE will preserve these directives, but will NOT read its network
# configuration from sourced files, so do not attempt to move any of
# the PVE managed interfaces into external files!

auto lo
iface lo inet loopback

iface enp5s0 inet manual
#PCI AsRock Gigabit

auto enx9cebe8c3766f
iface enx9cebe8c3766f inet manual
#USB Dell Gigabit

auto vmbr0
iface vmbr0 inet static
        address 192.168.100.10/24
        gateway 192.168.100.1
        bridge-ports enp5s0 enx9cebe8c3766f
        bridge-stp off
        bridge-fd 0

auto vmbr254
iface vmbr254 inet manual
        bridge-ports none
        bridge-stp off
        bridge-fd 0
#Host

auto vmbr50
iface vmbr50 inet manual
        bridge-ports none
        bridge-stp off
        bridge-fd 0
#Internet

auto vmbr1
iface vmbr1 inet manual
        bridge-ports none
        bridge-stp off
        bridge-fd 0
#lan

 

[spirit]

can you try to add

"
autoconf 1
accept_ra 1
"

in the interface where you need slaac.

?

I think ifupdown2 disabled it by default for security vs classic ifupdown1 enable it by default

 

[lixaotec]

@spirit

I didnt worked

ifupdown2 package seems very tricky with ipv6 and slaac, read their issues and think they do not priorized this.

I regret using it however that will makes me installing proxmox from scratch.

 

[spirit]

@spirit

I didnt worked

ifupdown2 package seems very tricky with ipv6 and slaac, read their issues and think they do not priorized this.

I regret using it however that will makes me installing proxmox from scratch.

you can still rollback, simply reinstall ifupdown1 "apt install ifupdown"

 

[lixaotec]

Just to note for others:

It worked again with add following line to the end of iface . then ifreload -a (thus you have to wait a while for router advertise)

pre-up echo 2 > /proc/sys/net/ipv6/conf/$IFACE/accept_ra


thanks @spirit and julien from ifupdown2
https://github.com/CumulusNetworks/ifupdown2/issues/178#issuecomment-725558706