Generally speaking, a Tier 1 array will have symmetric paths. In ALUA terms, both paths would be Active/Optimized. These have equal cost, and array LUN access would be evenly split (half the LUNs on one path, the other half on the other path.)
A Tier 2 array may have asymmetric paths. In ALUA terms, one path is Active/Optimized, and the other is Active/Non-Optomized. In this case, all the array LUNs in that group would use the A/O path, and the A/N path would be the failover path
In both cases we depend on the array to tell us which paths are active or preferred.
Hope that helps!
Daniel Isaacs Technical Marketing Engineer V-Series
Thanks for that, we were trialling an unsupported config with a HDS HUS150 behind a V6280. Dont ask why
One of the things i notices was we weren't able to get it running Active/active even though the HUS supports that kind of I/O my assumption was it was defaulting to active/passive due to it not quite understanding what array was connected to it. Which makes a certain amount of sense.