[SOLVED] lxc log issue

[RobFantini]

Hello
we use a cron script to check /var/log/syslog for certain error strings like this:

egrep -e oom-killer /var/log/syslog

for a long time we have lxc logs showing errors from other containers

for instance a simple dhcp container [ which runs no other servers then dhcp ] is picking up an oom for a video system:

dhcp-secondary
Apr 19 07:24:00 dhcp-secondary kernel: [3429553.490136] bc-server invoked oom-killer:
gfp_mask=0x100cca(GFP_HIGHUSER_MOVABLE), order=0, oom_score_adj=0
Apr 19 07:34:57 dhcp-secondary kernel: [3430210.561511] bc-server invoked oom-killer:
gfp_mask=0x100cca(GFP_HIGHUSER_MOVABLE), order=0, oom_score_adj=0

So any suggestions on how to prevent the cross logging?

 

[oguz]

hi,

this has been explained already a couple of times here.

basically the containers share the host kernel, i.e. there's no extra layer for kernel virtualization in containers.[0]
that's why you can see logs from "other containers" (because they all use the host kernel). if you need full separation between guests then you should use VMs.

so this isn't a bug/issue strictly. this might be seen as a drawback for usecases where containers are given to users, but it's also the reason containers require less overhead in comparison to VMs.

[0]: https://pve.proxmox.com/wiki/Linux_Container

 

[RobFantini]

Oguz - thank you. I had searched before posting but missed that.