Set net.core.rmem_max in an ArchLinux container


I want to set net.core.rmem_max in an ArchLinux container. I get the following error in the container,

# sysctl -w net.core.rmem_max=4194304
sysctl: cannot stat /proc/sys/net/core/rmem_max: No such file or directory

On the ArchLinux host it is available:

$ cat /proc/sys/net/core/rmem_max 

How do i set it in the container?

It’s a kernel issue. Either this file cannot be namespaced, explaining it being missing or it’s a kernel bug which causes it not to be exposed.

@brauner thoughts?

I tried it on two different host distributions (gentoo 4.14.143-gentoo and archlinux 5.4.25-2-lts). The sysctl
/proc/sys/net/core/rmem_max was not available in the containers of these machines.

Do you have /proc/sys/net/core/rmem_max in the containers of the Ubuntu host?

root@c1:~# ls -lh /proc/sys/net/core/
total 0

The naming core may suggest global kernel limits though, so those may not be namespace-able. Probably still worth asking the kernel folks about those though.