without the powerpath software I see I have 4 paths
2 standby and 2 active
but 1 active only has (I/O
with powerpath will that give me 4 paths active?
can I get more active paths by adding in extra hba?
Powerpath does have the ability to use all the path in an optimal way (which may or may not mean using all the paths - depends on the array and current workload).
You can get more paths listed as 'active' with another HBA, but wihtout PP, ESXi will always only use 1 path at a time (true for all arrays with ESXi).
RR is not supported on the CX3. Also, the CX3 is not supported at all with vSphere 5.
The CX4 does support RR with the right FLARE code revision (29 and above) and initiator settings (Failover Mode 4)
However - dont forget that round robin DOESN"T use multiple paths simulataneously - it just switches rapidly between them. If you want to use multiple paths *at the same time*, you need powerpath.
Meaning not supported at all.
VMware does not support the use of vSphere 5 with any CX3 array. HCL link: http://www.vmware.com/resources/compatibility/search.php?deviceCategory=san