Operation not permitted in privileged container

[kliment.toshkov]

Hi,

I have privileged container in which is needed to access devices on host machine.
Added in lxc.conf the following:

lxc.cgroup.devices.allow: c 196:* rwm

This was enough in kernel 5.4.x and PVE 6 to access devices in LXC when executing:

mknod /dev/dahdi/ctl c 196 0

However after upgrading to PVE7 and kernel 5.11.22 access to device in LXC is no longer available:

Unable to open /dev/dahdi/ctl: Operation not permitted

All necessary code is installed on host, compiled fine, kernel modules are loaded and everything works fine:

root@ic4:/etc/pve/lxc# dahdi_scan
[1]
active=yes
alarms=RED/LFA
description=T8XXP (PCI) Card 0 Span 1
name=TE8/0/1
manufacturer=Digium
devicetype=Wildcard TE820 (5th Gen)
location=Board ID Switch 0
basechan=1
totchans=31
irq=0
type=digital-E1
syncsrc=0
lbo=0 db (CSU)/0-133 feet (DSX-1)
coding_opts=AMI,HDB3
framing_opts=CCS,CRC4
coding=HDB3
framing=CCS/CRC4

So my question is how to allow access to devices in LXC as it used to work before updating?

 

[leesteken]

Just replace cgroup with cgroup2 for Proxmox VE 7.0 and up.
It has been mentioned here and there on the forum but I cannot find a good reference just now, sorry.

 

[kliment.toshkov]

OMG thank you very much! That did it. I spent hours today digging and did not find it :-(