Upgrade Flare no upgrade host agent OK or not?

if it's just a minor level upgrade i think you will be ok, but guess what's going to happen when you have a problem and you call EMC. First thing coming out of their mouth will be "You are running an unsupported version of agent/cli/admsnap, let's upgrade those and see if it fixes the problem" ...at least it's been in my experience.

If you have any scripts they will probably no longer work correctly as each version of navicli has small in the syntax so make sure you consider that. Other than that just talk with your CE or EMC support and see if the current version on navicli, and adminsnap are going to be compatable with the new version of FLARE. If it's compatable then don't upgrade the hosts.

Check the Navisphere Host Agent CLI Release Notes on powerLink for each version you will upgrade past or to and do the same for each layered application you are using SnapView, MirrorView etc. The release notes indicate supported older releases and will indicate any discrepancies this is especially important for the Navi CLI.
There were some infrastructure changes in the 22/24 timeframe that effect SnapView Clones and Mirrorview that require you to add a Secure CLI security file in order to continue to operate existing scripts.
The Host Agent is very stable and does not need to be upgraded, same with admsnap as this is operates on the server only.
We require that you upgrade the CLI client to the current release if you are using the Classic CLI but the older Secure CLI clients are supported with arrays at higher levels.
In general its a good idea to move to Secure CLI for all your scripts, besides fewer server upgrades, it offers better security and performance.

Has your question been answered ? If not what version of Flare are you currently running and what version do you need to go to ?