Unstretching a Pod

If you have followed best practices there is nothing required inside of SRM to unstretch a pod. With that being said, mistakes happen and it is important to be sure.

1. The array that will still own the pod is configured in SRM array managers. This will ensure that SRM can still control the pod now that it is only on one array.
2. The array that will still own the pod has existing and valid connections for all of the volumes in use. This will ensure that the VMware environment will still have storage access to the volumes when the one FlashArray is removed from the pod.

   So the first step is to verify array manager configuration.

   In this example I have a pod called testPod on stretched across two FlashArrays, flasharray-m50-1 and flasharray-m50-2:

   

   I want to remove it from flasharray-m50-2. In SRM, click on the array pair for testPod and choose Edit Local Array Manager from the Array Manager Pair drop down.

   

   Since I will be removing flasharray-m50-2 and the pod will remain on flasharray-m50-1, I want to make sure the address of flasharray-m50-1 is listed. If it is not, add it now:

   

   If you have made any changes. Click Save.

   Now verify it is listed in the remote array manager. Select the pair, then the Array Manager Pair drop down and then Edit Remote Array Manager:

   

   Same as above, ensure that the eventual surviving owner (flasharray-m50-1 in this case) is listed. But this time in the peer array(s) address entry:

   

   If it is not there, add it and click Save.

   The next step is to verify storage connectivity. This is standard procedure for any unstretch operation. The FlashArray will not let you unstretch from a FlashArray if the volumes in that pod have active connections to one or more hosts on that particular FlashArray. So, for any volume connections on flasharray-m50-2, they should also be connected to those same hosts on flasharray-m50-1. Below I currently have one volume in the pod (repeat this process for all of them):

   

   Click on the volume.

   Then go to the Connected Hosts and Connected Host Groups. In the vertical ellipsis menu, click Show Remote Connections:

   

   This will show the host(s) or host group(s) (depending on what box you are in) connections on both FlashArrays in the pod:

   

   Verify for every connection on the FlashArray you want to remove that there is a corresponding connection on the other array. In the case of host groups, ensure that the hosts in the host groups are the same (verify by looking click on the host group, then the hosts to verify the initiators).

   So for example, the host called esxi-02 is the same on flasharray-m50-1 in host group MountainView as the host esxi-02 in host group MountainView on flasharray-m50-2:

   flasharray-m50-1:

   

   flasharray-m50-2:

   

   To be extra sure, verify that the host themselves see all of the paths as live by looking at the FlashArray GUI on the array you want to keep the pod on. Click on Health > Connections and then the host name:

   

   Confirm that the host has at least two connections to both CT0 and CT1 that are marked as green. If one or both controllers do not have green connections, verify zoning (for Fibre Channel) or ESXi host configuration (for iSCSI).

   Once confirmed you can safely unstretch the pod.