Re: conntrack: will it restart after delete?

[Pascal Hambourg <pascal.mail@plouf.fr.eu.org>]

Hello,

sean darcy a écrit :
> I've had a problem with a udp connection being setup before DNAT, 
> occurred. See "where are my udp packets going?" Nov 15, 2008.
> 
> So just before setting up DNAT I'd propose to run:
> 
> conntrack -D -p    udp --dport 4569
> 
> but the user guide says this "blocks" the connection.

The user manual only says "this can be used to block traffic" (cut an 
existing connection) with proper ruleset and settings. It does not block 
traffic by itself.

> I only want to 
> flush/empty it, and let it start again with DNAT working.
> 
> Does this do it?

I guess so, although I never used conntrack (no need yet).
However I would run the conntrack command after setting up DNAT rules, 
because a packet could arrive between the two operations. Deleting a UDP 
conntrack entry should be harmless, as the next UDP packet would create 
it again anyway.