Re: [RFC PATCH net-next 0/3] netns: optionally inherit IPv4 TCP sysctls from old net

Nicolas Dichtel
2026-04-30T15:44:56Z

Le 30/04/2026 à 03:30, nmreadelf a écrit :
> a new network namespace starts with built-in TCP defaults.
> In container-heavy setups, operators often tune TCP sysctls in init_net and then
> need to re-apply the same values for each new netns.
>
> This series adds an opt-in mechanism to initialize per-netns IPv4 TCP sysctl
> settings from init_net at netns creation time.
>
> Behavior:
>
> Default is unchanged.
> When net.ipv4.netns_inherit_tcp_sysctls=1, new netns inherit
> TCP sysctl from old_net.

There is the same kind of sysctl for net.{ipv4,ipv6}.conf.{all,default}.*:
net.core.devconf_inherit_init_net.

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/admin-guide/sysctl/net.rst#n401

I'm not sure if it's acceptable to use this existing entry to control the TCP
sysctl.
At least, putting the new one in the same place + using the same template for
the name + the same values would be nice. Something like
net.core.tcp_inherit_init_net.

Regards,
Nicolas