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SyncMirror pool assignment planning for array LUNs

To set up SyncMirror with array LUNs, you must provide Data ONTAP information about which array LUNs are local and which array LUNs are remote.

For native disks, Data ONTAP automatically assigns a disk to the local pool or remote pool, as appropriate, or you can assign a disk to a pool. However, Data ONTAP cannot detect whether an array LUN is located on the local storage array (the local pool) or on the remote storage array (the remote pool). You must explicitly provide this information to Data ONTAP.

You want the data mirrored exactly the same on the two storage arrays so that if one plex becomes unavailable, all data can continue to be served. Your goal is to group the LUNs belonging to the two storage arrays, or two locations on the same storage array, into two SyncMirror pools. One is the local pool and the other is the remote pool. Then, when you later create a mirrored aggregate, the LUNs for the same plex are derived from the same pool.

To group the LUNs, you must identify the appropriate SyncMirror pool for each array LUN you are using to create the two plexes of the aggregate. To specify the correct pool for each array LUN, you must know which array LUNs are located on which storage array. Data ONTAP cannot determine this for you.

You need to ensure that each LUN set has the same number of LUNs and that the LUNs in each set are the same size.

If you are using one storage array, you need to ensure that each LUN is from a different disk group (RAID group) on the storage array.

Physical location of storage (assuming two storage arrays) Pool to which the array LUNs need to be assigned Command setting
Array LUN is on the storage array that is connected to the Data ONTAP system (the local storage array). The aggregate is created on this Data ONTAP system. (You can think of the Data ONTAP system as the owner of the aggregate.) Local pool (pool0) disk assign -p 0
Array LUN is on the storage array whose LUNs are to be used to mirror the array LUNs in the aggregate. (This is the remote storage array.) Remote pool (pool1) disk assign -p 1
Note: You use the -p parameter of the disk assign command to specify the SyncMirror pool assignment.