Will an HA install work across two private clouds?

[raymondnorton]

We will install a new 3Cx system at one of our WAN member k12 school districts in a few months. However, a few months later, they will migrate to a new WAN (not operational yet), and the original WAN/Cloud will go away. Would an HA install work if the primary server was at site A and the secondary server was at site B, if we created an IPsec tunnel between two Fortigates across the Internet, or is it an impossibility because they would not be on the same subnet (provisioning)? If it would work, we would cut over to the secondary server when the original WAN is shut down and, hopefully, not have any downtime.

Thoughts?

 

[Evolute IT]

We will install a new 3Cx system at one of our WAN member k12 school districts in a few months. However, a few months later, they will migrate to a new WAN (not operational yet), and the original WAN/Cloud will go away. Would an HA install work if the primary server was at site A and the secondary server was at site B, if we created an IPsec tunnel between two Fortigates across the Internet, or is it an impossibility because they would not be on the same subnet (provisioning)? If it would work, we would cut over to the secondary server when the original WAN is shut down and, hopefully, not have any downtime.

Thoughts?

Use FQDNs for provisioning, with Split DNS and a failover script to update the DNS record.

That's how we do failover between sites when a VPN is there. Otherwise we use public FQDNs.

 

[raymondnorton]

That is what I read in the docs, but I was not clear about how the remote server could provision phones on the other subnet.

 

[Evolute IT]

That is what I read in the docs, but I was not clear about how the remote server could provision phones on the other subnet.

As long as it uses the FQDN, it doesn't matter.

If you use a 3CX FQDN, it will autoupdate the public IP, but you still need to update the Split DNS (internal private IP) to reflect the active server. You can use the scripts for this.

 

[SteveITS]

@raymondnorton Note the HA for 3CX is via scheduled restore, not a live sync. An Enterprise license has a 5 minute TTL on a 3CX hostname. The SBCs, phones, apps, etc. will all point to the hostname.

 

[raymondnorton]

Related question: Does HA need to be configured at installation, or can it be done later during a restore? I ask because our failover network will not be operational for a few months, so I am hoping we can do a single install now and set up the HA configuration at a later date.

 

[SweetAction]

You can setup HA at any time.