3CX Linux Using Wrong Interface After Reboot

[l2]

We have a client running Version 20.0 Update 5 (Build 551 Release) on Linux in a Hyper-V environment. After an automatic update on 3/4 and again 3/18, we experienced an issue where after the reboot the system tries to route WAN traffic over the secondary NIC. The only fix we have found so far is to disable the secondary NIC in Hyper-V Manager and reboot 3CX then re-enable the secondary NIC after 3CX is back up. Primary NIC routes to WAN and secondary NIC is where the phones are attached. I have verified that the proper NIC is set in Admin > Advanced > Network > Default Gateway.

Has anyone else experienced this and have a permeant solution or ideas?

 

[fxbastler]

... and have a permeant solution or ideas?

Yes: use only one NIC.

That's how it's described everywhere, over and over again.

 

[l2]

Yes: use only one NIC.

That would be my preference but unfortunately that isn’t an option for this client at this time. While I can appreciate “best practice”, this has worked flawlessly since we upgraded from v18 until now. “Use only one NIC” is a workaround and not a solution to a feature in the system.

 

[fxbastler]

Then use a firewall which does the network separation.

 

[NicholasP_3CX]

Remove the default gateway from your secondary NIC.

If you have a secondar NIC that routes traffic off network to a sIP provider for example, use a persistent static route, but the default gateway should only be on ONE interface.

https://www.3cx.com/blog/docs/network-configurations-supported-3cx-phone-system/

 

[l2]

Remove the default gateway from your secondary NIC.

Thanks, Nicholas! That is likely the problem. I will test this change with a reboot at close of business today.