Ran across and interesting situation.
4 node 2012 R2 Hyper-V cluster. The cluster uses a direct connection to shared storage so there is no network needed for that. There are two subnets: one for domain traffic and one for live-migration and heartbeat.
On top of that, a 2 node in-guest SQL Server 2014 Cluster. There are three subnets: one for domain traffic (same as above), one for heart beat, and one for migration.
Along with a 2 node file share cluster with three subnets. Again, one for domain traffic (same as above) and one for heart beat and one for migration.
While each cluster uses different subnets (the all share the domain subnet for domain traffic), everything is on the same VLAN. Everything is Windows Server 2012 R2. There are 12 servers on this network. There is no other traffic other than users connecting through a firewall with a single application. All other traffic is blocked. There is no Internet traffic allowed to this network. At all. Everything connects through a 10G switch.
Question: Is having all that clustering on the same VLAN, despite the usage of subnets, terrible? What is our level of screwed-ness? I watched on machine fail over, seemed to work fine. Just a couple of seconds. But still, thought I would ask. :)
Oh, the validate cluster wizard gives it all green lights across the board.
JamesNT
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