SRDF/A Concat META Expansion

Am back !!

Today am gonna take you on a issue which I faced during a recent device expansion in Symmetrix VMAX.

Adding additional 100 Gigs to an existing RDF Concat Meta. But how ???

(Click to expand)

1) Create devices on R1 and R2 and R2 Clone as per their hyper sizes.
2) Terminate Clone Session on R2
3) Disable consistency on R1 group
4) Suspend RDF links for that group
5) Do a delete pair on the R1 group. This is an IMPORTANT step.
6) Add the created hypers to the existing META on R1 side (Remember this procedure is exclusively for Concat META expansion)
7) Add the created hypers to the existing META on R2 side.
8) Add the created hypers to the existing META on R2 Clone.
9) Establish a new R1 - R2 Sync with the mode ACP_Disk. This would be a fresh sync between R1 and R2 as the new devices which were added to the concat META will adjust the META Geometry. Since this sync will take time, its better to set the mode to ACP_DISK.
10) You can either create a temporary RDF group and later on move the pair to the actual production group or you can directly add the pair to the actual production group.
11) Once the device state changes to "Synchronized", we have to change the mode to ASYNC and then suspend the RDF group to move the pair to the actual group.
12) Once the move pair operation is complete, we can resume the RDF links and enable the consistency on the actual group which will show the state of the device pair as "Consistent".
13) So we have completed the R1 - R2 setup. Now moving over to the R2 Clone setup.
14) Since we terminated the previous clone session, we will be using the same set of clone devices and will create a clone pair.
15) You can create a pairing file with the R2 and R2 Clone device(s) and create the clone session with the -PRECOPY option. This will start the background copy of the device and the host can access data through it. 
16) You can keep the devices in precopy mode always or you can activate the clone copy which will change the status of the devices to "Copied" status.

Thats it !.. Your R1 - R2 and R2 Clone Concat META expansion is complete. You can ask the platform guys to expand the drive at their end so that the new size would be visible to them.