Mismatch of HBA Speed

[gkapoor]

Hey Guys,

Just wanted to ask, What could be the possible issues if HBA speed on HOST is different from HBA speed on Array.

Example.

HOST HBA : 8 GB/s
Array HBA : 4 GB/s

Would that be auto negotiable? Would the HOST HBA adjust itself to Array HBA speed?

Do you think this mismatch would really cause performance issues?

[afidel]

It works fine so long as you're not using direct attach (ie you are using a FC switch in between).

Remember you can have a host with 2x 8Gb ports and an array with 24x 4Gb and then you'll be able to get 16Gb to that host assuming you have sufficient disk to push that throughput and are using multipathing.

[Richard Siemers]

Going through the switch, I would also zone each 8gb HBA to 2 different 4gb storage ports