I've been digging around trying to find an answer but haven't really found anything definitive. I think I know what the answer is, but wanted to get real world feedback and possible best practices.
I'm looking at a scenario with a single filer (dual head) that is cabled fully redundant across two separate FC switches. Head one 0a goes to switch 1, 0b goes to switch 2. Head two 0a goes to switch 2, 0b goes to switch 1. There are a few VMware hosts, each with a vmhba into each switch. I'm doing quite a bit of cleanup in the back of the rack and need to perform the following:
1. Replace the power cable on FC switch 2.
2. Replace all the FC cables going into the filer heads.
I need to do all this without downtime. Since it is fully redundant, I should be able to do one thing at a time without any interruptions.
I'm hoping that the answer is going to be that FC is an intelligent enough protocol that it can handle this without any provisions and no risk of data corruption.
I'm expecting the answer to be something like remove the paths in VMware, shutdown FC adapters in the filer, then perform maintenace. While not difficult, just a huge pain in the backside when looking at multiple datastores, each with 4 paths, presented on multiple hosts.
Let me know if anyone has any experience with this they wouldn't mind sharing.
You are absoultey right these tasks can be performed with any distrubtion to the ESX hosts/virtual guests what gets people caught out are the following.
Bad Zoning or Incorrect zoning across front end ports.
Incorrect pathing policy set on ESX hosts you can verify this with your storage vendor what it should be set to.
If you have these things right your good to go.