Re: Confirming conntrack behavior on environments with multiple network namespaces
Florian Westphal <[email protected]> Fri, 26 Sep 2025 16:03:19 +0200
| Newsgroups | gmane.comp.security.firewalls.netfilter.general |
|---|---|
| Message-ID | <[email protected]> |
Antonio Ojea <[email protected]> wrote: > > Or add 'notrack' rules in init_net for the netns originating traffic. > > Or create a netns, enable conntrack and then only create connections > > to addresses reachable via loopback. In all these cases init_net won't > > be affected by the net namespace. > > It will be hard to disable conntrack in init_net, a lot of > functionality relies on NAT in kubernetes and is not owned by the same > component Sure, I understand that no-conntrack-in-init-but-in-another-namespace is atypical. > > That will only monitor that namespace, I'm not aware of a global counter. > > > > Can this be a feature request? having a global counter can easily > monitor the load factor of the system, but I'm not familiar with > kernel conventions and having some global counter may be discouraged Not sure we should add one, it will result in some overhead for no good reason. Maybe /proc/slabinfo is enough for your use case? nf_conntrack has its own (global) memory pool, it should provide a reasonably good estimate across all netns.