I have a WSFC with SQL Server 2016 Enterprise Edition and 4 Availability Groups. Each server has 1 CPU with 6 cores @ 3.4GHz and 256GB of RAM.
Currently I have one instance on each, they serve 4 Availability Groups with a total of ~300 GB data in 95 databases.
I have the task of migrating more databases (35 databases, 235 GB data) into this environment, which I'm sure would be a breeze - had it not been for the fact that these databases come from a cluster with another collation. Hence, I'm thinking of adding an instance on each server and creating a separate Availability Group for this collation.
To help keep things sorted and sort of simple I will add an IP address on each server for the new instance. That way I can address both instances on port 1433 and won't need to sort that out in the availability Groups Creation - at least that's my thinking. (I've used this approach on a single server with 3 instances - they all have their own Ip addresses which removes the need to address them by instance name - keeps it easy in case the db needs to migrate to another server. )
I found a similar question from a few years back but since there was no evident reason for the multiple instances the TS received a lot of whys, donts and whats. I my case I really need to have an extra instance due to the collation issue, my question to the Community is: is there anyone who could tell me "Yes" or "No"? And if either answer - could you please give me a good motivation?
If I can't add the instances I would have to go with another server, and due to the license costs of Enterprise Edition this would then be a non-clustered solution - reducing uptime, complicating patch routines, removing redundancy and so on. So: could I do this?