[SOLVED] IP Settings not applying to new LXCs

[Astaroth]

Hi,

SOLVED - LXC is privileged as per Jellyfin's documentation which disables nesting by default. Adding nesting resolves the issue.

I'm trying out Proxmox for the first time and everything was going well but all of a sudden IP settings have stopped working for new LXCs (I haven't tried VMs). The only thing I remember doing when it stopped working was to delete and re-create a container. When I start a new container with a static IP or DHCP the result is as follows.

ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host noprefixroute
       valid_lft forever preferred_lft forever
2: eth0@if58: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
    link/ether bc:24:11:05:07:30 brd ff:ff:ff:ff:ff:ff link-netnsid 0

If I set the address manually as below, it works fine until I restart the container. I know the commands below are not persistent, but I'm just showing that the network is working, it's just not getting the IP via the Proxmox config file. The IP is reserved on the router and I've checked for conflicts.

ip addr add 192.168.0.202/24 dev eth0
ip link set eth0 up
ip route add default via 192.168.0.1
ping google.com
PING google.com (142.250.151.100) 56(84) bytes of data.
64 bytes from st-in-f100.1e100.net (142.250.151.100): icmp_seq=1 ttl=112 time=20.2 ms
64 bytes from st-in-f100.1e100.net (142.250.151.100): icmp_seq=2 ttl=112 time=19.5 ms

Here is the config file for the LXC:

arch: amd64
cores: 2
dev0: /dev/dri/renderD128,gid=993,mode=0660,uid=0
hostname: lxc-jellyfin
memory: 6144
net0: name=eth0,bridge=vmbr0,gw=192.168.0.1,hwaddr=BC:24:11:05:07:30,ip=192.168.0.202/24,type=veth
ostype: ubuntu
rootfs: local-lvm:vm-202-disk-0,size=200G
swap: 512

If I restart an existing container it keeps the IP and connects as expected. I've tried DHCP, different IP addresses, deleting the container again and re-creating it, creating a completely different container with a different name and ID, restarting the host and restarting the router. I'm using Proxmox 9.0.5 and the container is Ubuntu 24.04. I've tried 25 too, but for some reason I just get a black screen and cursor when I use that. Anybody know what might be causing the problem please?

Thanks

 

[Aaron_Nad]

I'm experiencing the same issue.
Ubuntu 24.04 LXC that wont use either static ip or dhcp definition.
No amount of restart, hard shutdown works.

Edit: My LXC is unprivileged, setting the Nesting option to checked resolves the issue after a reboot.
Removing the Nested: enabled setting and rebooting the LXC then prevents the IP settings from working.

Seems to be a problem with 9.0.5


I did a bog standard setup
Download the 24.04 LXC template via proxmox
Set the ip settings as follows

root@mini-pve01:~# cat /etc/pve/lxc/100.conf
arch: amd64
cores: 2
dev0: /dev/dri/card1
dev1: /dev/dri/renderD129
features: mount=nfs
hostname: plex
memory: 16384
nameserver: 192.168.50.100 192.168.50.101
net0: name=eth0,bridge=vmbr0,gw=192.168.50.254,hwaddr=BC:24:11:44:C8:8E,ip=192.168.50.8/24,tag=50,type=veth
ostype: ubuntu
rootfs: SSD:100/vm-100-disk-0.raw,size=40G
searchdomain: domain
swap: 512

This will not get an IP in the LXC on boot

Enabling nesting works
Removing nesting breaks it again