HA over switch on Dedicated HA Link

Question

Hi 
 
 We have 2 datacenter and we would like to configure 2 Sophos XG 550 in HA, one in each DC. Nowadays we have a fiber channel connecting the DCs. Is possible connect the PortA3 (Dedicated HA) in the network switch and use the same trunk fiber with VLAN ? 
 
 In my tests, I tried to connect the PortA3 in the switch, but the auxiliary Sophos keep rebooting. When I connect a directed cable, it's works.

Thank you.

LuCar Toni · Answer

Hi, 
 i link my answer to such questions here: 
 https://community.sophos.com/products/xg-firewall/f/network-and-routing/90780/utilizing-high-availability-between-an-office-and-co-location-in-data-center 
 I am not a fan of split brain scenarios. Instead i use 2x HA in each location and cross connect them. 
 
 You need to consider, if the Link between both appliances break, you will have a Master-Master Situation, which can/will cause trouble. 
 UTM offers something like Backup Interface, but tbh, most of the time, those backup interfaces to check the connection in such setups, is build on the same "wire". So basically, the main connection dies, the backup dies too. 
 I tried to find a Feature Request for this on Ideas.sophos.com, but found only one with 2 votes. 
 https://ideas.sophos.com/forums/330219-xg-firewall/suggestions/34644892-high-availability-with-backup-interface 
 So feel free to vote for it.

Plus: If the aux reboots, seems like the link is not "direct" attached. Maybe something is blocking the logical way to the aux appliance.