sundance-communications.com/forum Forums TDM Business Telephone Systems Samsung Telephones & Systems SPNET "blocking"?

I have a 12 node Samsung SPNET with 6 - 7100, 2 - 7030 and two 7200s (MCP) (Customer refuses to upgrade to cloud)
Everything works fine till one of the nodes loses internet... then other systems start having issues calling the other nodes that ARE up...
My theory is the NAT tables in the routers/firewalls are getting full from the repeated attempts at making intercom calls to other nodes.
If that is the case... how can this be remedied? TCP or UDP timers in the firewall? If the timer is reduced, wouldn't it cause issues with calls when everything is fine?

I am not at all familiar with SPNET or how it communicates, but I can't see it causing an abundance of entries in a NAT table just because another extension/system is unreachable. To do so would mean the PBX send each individual request (for the same call) from different port numbers.

It's probably worth running Wireshark while the issue occurs to see if a smoking gun appears...

Doe the issues they experience have to do with degraded audio? Or do calls simply fail to complete (and if so what message do they see)?

I believe it's a "No User Response" error from the pbx. Had to clear an issue this am on this specific customer.
The one 7200 causing the issue was unreachable via the maintenance software (TCP 5090), but reachable via an IP set at my location. Rebooted the system via 811 and everything came back just fine.
It's difficult to get Wireshark in place... I have to act quickly to reboot which ever pbx is causing the issue and get them back online.

What firmware level are the OAS's or MGI's? I had a similar issue on a system that's been installed for 15 years without a hiccup then the network went down and the OAS's didn't come back without a reboot or reseat the OAS card. I found out that particular OAS version had a known issue an update corrected it.