ONTAP Discussions

Can I join shelves from two separate stack into one stack




We have FAS8060 running 8.3.2 CDOT.  We have two stacks , Stack A have 5 shelves 30-34, Stack B has one shelf 40. They are exactly the same shelf model and speed and the disks are also the same. I want to combine them to free up the SAS port. Im guessing this will require downtime? I am thinking, re-id shelf 40 to shelf 35 then add to Stack A. I just need to know if downtime is required.







Downtime is not needed. You can hot-add a SAS disk shelf to an existing stack of supported SAS disk shelves.

Refer the sections below in the link: https://library.netapp.com/ecm/ecm_get_file/ECMP1119629

Changing the disk shelf ID page 10

Hot-adding a SAS disk shelf page 12

If this post resolved your issue, help others by selecting ACCEPT AS SOLUTION or adding a KUDO.


Hot add is easy - hot move is less so.


If you want to change shelf ID, then yes, downtime is required.


If you just want to merge stacks, a takeover/giveback/takeover/giveback cycle is required.


  1. Have A takeover B.
  2. Halt B.
  3. Unplug the B side of both SAS stacks from A's controller
  4. Unplug the A side of both SAS stacks from B's controller
  5. Rewire B side without plugging back into A
  6. giveback B from A
  7. takeover A by B
  8. Rewire A side of the SAS stacks.
  9. Plug A side of stack back into B
  10. Plug B side of stack back into A
  11. giveback A from B, and that should do it 

If the above sequence is confusing, I encourage planned downtime, to avoid unplanned downtime. 


In my opinion I prefer to do a quick downtime windows



- First plan very well the new SAS and ACP cabling, send ASUP to know your old configuration, then stop applications, disable cluster and halt filer.
- Wait until LOADER prompt on both nodes
- Make new SAS and ACP cabling
- Set new shelf ID and restart shelf to commit the change
- On both nodes from LOADER prompt tipe "boot_ontap menu"
- in 1-8 menu select option 5
- Validate new shelf ID change and disk showing correctly
- Then halt, and boot_ontap
- When filer comes online enable cluster and validate cabling

- Restart Applications

- Send new ASUP ending downtime windows.

In my opinion is the more secure and reliable way to make the work you want.

good luck.


Miguel Valls