IPSec tunnel with redundancy

[froussy]

Good day!

i'm managing a compagny with multiple store/site.

I'm using pfsense gear for all sites, except my office (172.16.35.0/24) which is an Edgerouter ER-8-XG

Actually, every sites (including my office) are connected through IPSEC to the head office (192.168.4.0/24).
I want to create a second tunnel, from every sites to my office, so if the headoffice goes offline, everything will pass through my office

What is the best way to do that

thanks in advance.

[Jose Carlos S]

@froussy Hi, may be IPSEC (VTI) + OSPF/BGP???