Both the ESX host can be managed by single vcenter as long as Site A and Site B esx are able to communicate to vcenter and with required ports are open.
No need to create cluster at all as we got a total of only 2 servers. As you can create a datacenter and add host directly to the datacenter.wiht server name siteAesx and siteBesx.
- volumes will be replicated between Site A en Site B
- what is the best way to design the network so Site A can use Site B as failover and vice versa?
Same network Vlan has to be there in site A and site B.so in case of failover replication between storage can be breaked and vm in the site B will be regirested to ESX host in site B and start providing services.
- I guess i need to manually change router configuration on active site when one site fails?
Yes there should a policy or a rule placed that when router in site A is not aviable the traffic should go via router in site B. Speak to your network admin on this.
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