Hi, first I'd recommend getting the nomenclature standardized so we all know what we're talking about PSCA=PSC. It's just PSC. No 'A'.
1/ I have 2 remote sites with each a VCSA and a PSCA, ELM enable and even domain SSO (version 6.5).
I'm searching a solution in case of PSCA and network failure (between the 2 sites) in same time without using VDP.
I am looking for a solution to automatically backup the PSCA except using VDP.
Does anybody can help me ?
If there's a network failure between two sites and the link is broken, no type of backup/restoration job is going to help you. The PSC relies upon this link and so if it's down it's not a problem with the appliance. If you meant "if the PSC is down" then your best option, while still on 6.5, is to use a load balancer in front of two PSCs that are replicas. Failover will be transparent and the second PSC will take over duties.
If you're using VDP, you're out of luck. There's no automatic restore function there. And, furthermore, VDP is EoL and I think EoGS, so there's no point in using it any more when there are so many other programs out there that are infinitely better. Get off VDP as soon as you can.
2/ It seems the external powerCLI function "VCSA-BackupToFile" only works to backup VCSA (based on the service "com.vmware.appliance.recovery.backup.job").
Is it true ?
If no please have you a script example ?
Yes, to my knowledge. I'm not entirely sure what you're asking though.
3/ In case of using VDP to backup the appliance, Is there a special procedure to restore a failed PSCA ?
See answer to #1. Don't use VDP in the first place. As far as a special procedure to restore (if restore even works which it doesn't half the time), then no. It's just a VM. Although you will have to target an ESXi host and not vCenter since, presumably, vCenter will be down.