Preferred Mount - Shadowing

[Chris O]

We have a number of systems with dual-redundant HSx controllers. The drives on them are Phase II(host based) shadowed. We usually try to split the shadowset members between controllers. From a performance standpoint, is it better to have both members of a given shadowset on one controller or have them split between controllers? Thank you, Chris

[comarow]

Yes, you are on the right track.
Not only splitting controllers will improve performance, but provide greater redundency.

Good job.

[Eberhard Wacker]

Besides the redundancy advantage you have in general you have to set the preferred ways of your shadowset member disks explicitly (one to controller A and and one to controller B) to take advantage of your environment And this should be done on a regular basis to reset realtime changes after a contoller restart and such things.
Cheers,
EW