We have FAS2020 HA controllers and also have DFM (Operations Manager) for monitoring the controllers. What performance statistics need to be looked at to help us plan for upgrading the controllers? We've been adding VM's over the years and I really do not have a good understanding into which monitors would give me indications that it is time to move up to say a 2040 or the new 2240. Can anyone point me to a best practices document? Thanks.
My personal guidelines when upgrading from a 3020 to 3240 was 1) CPU load on the controllers 2) Shelf/drive count. I was getting to the point where I wouldn't be able to add more shelves and the CPU load was 50-60% on each controller. In a failover situation, you need to ensure you have enough capacity to run your workload without performance problems.