3cx Failover/Backup SIP Trunk

[Aung Phyo]

I would like to confirm the feasibility and best-practice configuration for a planned failover deployment using 3CX.

Current and Planned Setup

Main Office (Primary 3CX Server)

• Existing SIP Trunk from MPT: 14 DIDs / 80 concurrent calls (direct cable connection)
• Plan to add a new SIP Trunk from MPT (direct cable connection)
• Both SIP trunks will operate simultaneously during normal operation.

Branch Office (Secondary / Failover 3CX Server)

• The Secondary 3CX Server will be relocated to the Branch Office.
• Main Office and Branch Office are connected via local LAN routing.
• The new SIP trunk will also be directly connected at the Branch Office.
• This SIP trunk should be used by the Secondary 3CX Server during failover.

Expected Behavior

• During normal operation, the Primary 3CX Server should use both SIP trunks.
• When the Primary Server becomes unavailable, the Secondary Server should automatically take over and operate using the new SIP trunk located at the Branch Office.

SIP Trunk Details

• Existing MPT SIP Trunk (Main Office): 14 DID / 80 concurrent calls
• New MPT SIP Trunk (Branch Office): 1 DID / 10 concurrent calls

Questions

1. Is this failover with different SIP trunk using design supported by 3CX?
2. (How SIP trunk work? It's working look like backup trunk?Does a SIP trunk automatically function as a backup trunk, or does it require specific configuration to provide failover?)
3. Could you please provide best-practice guidance for configuring this scenario?

 

[paulodagraca]

Hello Aung Phyo,

The 3CX can have 5 route's at the 'outbound rules'.
Meaning that it is easy to setup a failover, that is 'HOT Standby'
When the first SIP Trink does not work or is full, the call will failover to the second SIP Trunk automatically.

So the Main Office will have
1) Trunk to main SIP privider
2) Fallback SIP trunk for Main office

And the Brach Office will have
1) Trunk using Primary main SIP provider
2) Fallback SIP trunk for Secondary server

The Primary 3CX server will be active and a perfect copy will be ready on the secondary 3CX server to take over.
When it does fall back to the secondary 3CX server, it should have a FULL backup, so working with same details as above.

The 3CX servers will be able to fallback
The SIP Trunks will also be able to fallback to a standby SIP trunk.
However these 2 things do not work together, meaning if the 3CX server will failover, it does NOT change any trunk, and the other part where the SIP trunk will fail, it will NOT change 3CX server.

Paulo

 

[Elil_TeleProTech]

Hai,

for SIP trunk failover, You can check with telecom to provide the primary sip trunk and backup sip trunk and use a SBC to manage the fail over between the SIP trunks. so u can maintain the same DID and when primary sip trunk fails, from telecom side, incoming call wil hit backup SIP Trunk. some telecoms provides, backup sip trunk in branch offices.

Thank u
Elil