I have a haproxy server which gets limited to some 60k connections. I think it is because of ephemeral port limit as I have 1:1 connection mapping, so all my outgoing connections go to the same server.
Here is what I think could help me: I can add a new network interface (eth1) with a new IP. I would then add a duplicate backend server definition and I believe the new destination will get a new ephemeral port limit as long as it uses a different interface. This should let my connection counts grow.
However, I can't seem to find a way to force haproxy to use eth0 for one backend server definition and eth1 for another. Is it possible to do that, or are there other ways of achieving what I need?
The system in question is running Debian and haproxy 1.4.8 (default on Debian).
From HAProxy manual, section 5:
Florin's answer is great.
Failing that (say, if this wasn't HAproxy), a workaround would have been to configure an address in a separate subnet on the secondary device.
The backend server would need to be reachable in that subnet as well, of course - the new
server
declaration would not be a duplicate, but rather an independent entry that would incidentally end up at the same machine.