Problem with pseudoterminal in container

[Matus]

Hi,

on one of our nodes in the cluster, appears problem with /dev/ptmx, after one of latest actualisation.

Command
ls -la /dev/ptmx /dev/pts/ptmx
gives on node:
crw-rw-rw- 1 root tty 5, 2 Mar 11 12:26 /dev/ptmx
c--------- 1 root root 5, 2 Mar 7 15:07 /dev/pts/ptmx
and on LXC container:
c--------- 1 root root 5, 2 Mar 7 15:07 /dev/ptmx
c--------- 1 root root 5, 2 Mar 7 15:07 /dev/pts/ptmx

Users (except root) have problem using programs like Screen.

After:
chmod 0666 /dev/ptmx
it works well.
But after restart of system problem appears again.

Have you any idea how to permanent solve this problem?

 

[oguz]

hi,

can't reproduce here (screen works for root and non-root user in and outside container). can you tell more?

-> which container are you using? pct config CTID
-> pveversion -v
-> you run this command inside the container or outside? where does the problem occur?

 

[Matus]

Above first ls is outside container on node
second ls is inside container

Problem occurs inside container when user try to use screen utility.

When I try to run this as user, I receive error:
sudo chmod 0666 /dev/ptmx
sudo: no tty present and no askpass program specified

After running chmod as root inside container everything is OK - users are able to use screen util - until next restart of system.

pct config 104
arch: amd64
cpulimit: 24
features: nesting=1
hostname: web.sofia
memory: 32768
net0: name=eth0,bridge=vmbr0,firewall=1,gw=X.X.X.X,hwaddr=22:CB:AE4:EF:0D,ip=X.X.X.X/24,type=veth
net1: name=eth1,bridge=vmbr1,firewall=1,hwaddr=C6:16:35:46:22:CF,ip=X.X.X.X/24,type=veth
onboot: 1
ostype: debian
rootfs: zfs-containers:subvol-104-disk-0,size=90G
swap: 16384

pveversion -v
proxmox-ve: 6.1-2 (running kernel: 5.3.18-2-pve)
pve-manager: 6.1-7 (running version: 6.1-7/13e58d5e)
pve-kernel-5.3: 6.1-5
pve-kernel-helper: 6.1-5
pve-kernel-5.0: 6.0-11
pve-kernel-5.3.18-2-pve: 5.3.18-2
pve-kernel-5.3.13-1-pve: 5.3.13-1
pve-kernel-5.0.21-5-pve: 5.0.21-10
pve-kernel-5.0.21-1-pve: 5.0.21-2
pve-kernel-5.0.15-1-pve: 5.0.15-1
ceph-fuse: 12.2.11+dfsg1-2.1+b1
corosync: 3.0.3-pve1
criu: 3.11-3
glusterfs-client: 5.5-3
ifupdown: 0.8.35+pve1
ksm-control-daemon: 1.3-1
libjs-extjs: 6.0.1-10
libknet1: 1.14-pve1
libpve-access-control: 6.0-6
libpve-apiclient-perl: 3.0-3
libpve-common-perl: 6.0-12
libpve-guest-common-perl: 3.0-3
libpve-http-server-perl: 3.0-4
libpve-storage-perl: 6.1-4
libqb0: 1.0.5-1
libspice-server1: 0.14.2-4~pve6+1
lvm2: 2.03.02-pve4
lxc-pve: 3.2.1-1
lxcfs: 3.0.3-pve60
novnc-pve: 1.1.0-1
proxmox-mini-journalreader: 1.1-1
proxmox-widget-toolkit: 2.1-3
pve-cluster: 6.1-4
pve-container: 3.0-19
pve-docs: 6.1-6
pve-edk2-firmware: 2.20191127-1
pve-firewall: 4.0-10
pve-firmware: 3.0-5
pve-ha-manager: 3.0-8
pve-i18n: 2.0-4
pve-qemu-kvm: 4.1.1-3
pve-xtermjs: 4.3.0-1
qemu-server: 6.1-6
smartmontools: 7.1-pve2

 

[grin]

It doesn't seem to be resolved and I observed the same on v7.1.

ptmx is mounted 0000 root:root and fstab is empty.

devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,mode=600,ptmxmode=000)
devpts on /dev/ptmx type devpts (rw,nosuid,noexec,relatime,mode=600,ptmxmode=000)
devpts on /dev/console type devpts (rw,nosuid,noexec,relatime,mode=600,ptmxmode=000)
devpts on /dev/tty1 type devpts (rw,nosuid,noexec,relatime,mode=600,ptmxmode=000)
devpts on /dev/tty2 type devpts (rw,nosuid,noexec,relatime,mode=600,ptmxmode=000)

I'll check whether upgrading to 7.2 changes anything, I don't readily see what mounts devpts on the CT.