VMWare Latency Errors

I have 2 Drobo SANS (B1200i). I have 3 ESX 5.1 hosts attached to the DROBOS via ISCCI. The Drobos were installed a while ago, but not much was running on them. Recently, I have moved a major file server, a document management system, a print server, and 2 SQL databases to the Drobos. Since this heavy usage, my ESX hosts are throwing errors… volumes are losing connecting to the storage and then recovering. These error messages are constant.
VMware has reviewed the logs and told me that this is a storage issue. The storage just can not catch up and these latency errors are occurring. Speaking with Drobo care has not been fruitful. They have told me to switch to single redundancy state, which I have done to no avail. At this point, I am worried, if I made a right technology and decision. May be there are ISCCI settings that need to be tweaked. I am looking for anything at this point.

hi, maybe some settings need tweaking, or possibly it is too slow for your needs,
but one thing to bear in mind is that a drobo will usually become sluggish after a large amount of data is written to it/modified until it sorts itself out… this might just be a few hours or maybe a day or so depending on the data…

if you just moved all these systems onto it, and started using them, it might still be trying to self-optimise the data, inbetween all of this usage… and if there is a period of time where you can give it a bit of breathing space, it might finish and subsequently perform better.

maybe not the best thing to hear, if youve just moved all of you production systems onto it in one go, but it might be a factor?