A Mikrotik will hold many, many thousands of connections. Don't know
what the limit is, but I have seen tens of thousands of connections in
the connections list.
Also, there is an option in the 13.2 (build 34) firmware that allows you
to bump up the NAT table to 8096 (not to mention that you can now watch
it via SNMP).
bp
On 10/22/2014 5:29 PM, Ken Hohhof via Af wrote:
I have a complaining customer who I’m becoming convinced is exceeding
the NAT connection table in their router. Can I trust the numbers here:
http://www.smallnetbuilder.com/lanwan/router-charts/bar/77-max-simul-conn
This would indicate a mid-range route like a typical N600 probably
supports around 4,000 connections. I'm not sure why this is, if you
look at the RAM specs for any of these routers, it doesn't seem like a
technical limitation, it's almost like they are artificially limiting
the connections by price for marketing reasons. But I think this
customer has something like a Netgear WNDR3400.
Anyway, am I barking up the wrong tree, or is this a possible or even
fairly common situation? I don't see any evidence this customer is
doing Torrents, but there seem to be a lot of TCP connections, and a
lot of apps that seem to have 4-10 or more connections open.
Including Pandora, not sure why Pandora would need so many connections.
Please note, the SM is bridged, I am not doing NAT in the SM.
Is there any way to prove this other than give them a Mikrotik?
And on a Mikrotik, can I tweak the UDP/TCP timeouts to flush out idle
connections faster? Seems like even with infinite memory, there are
only 65K possible ports for NAT/PAT and you would run into port
exhaustion.
