Ok so I was told wrong about the ports on the SAN’s. Both ports on the HP 4300g2’s are bonded as adaptive load balancing. But on the switch the ports are not bonded for either SAN. (Juniper 4200 switches)
ALB is not meant to have any special configuration on the physical switch side, that's fine.
Each san has 8 drives (7.2krpm, 1TB, SAS 6bgps) Raid 5. The sans are in a mirror. (all info from the SAN's) there are 2 lun's with about 20 vm's each.
Wow, eight 7.2k RPM drives in RAID5 sounds really bad for 40 VMs. This makes me extremely doubt the issue is really bandwidth related. Just check (r)esxtop or Datastore/Disk latencies in the performance charts when you notice slowness. It's very likely that your disks just can't handle the IOs your VMs are generating.
