Replacement of idas1 Disk Array with a New One
         - Anubhav, Feb 20, 2018


Preparation
============
* copy ida & root users' crontab on idas1 to idas2, and vice versa

* edit relevant files to stop NFS export on next reboot.

* sync idas2 with idas1 to have most recent changes ...
   - archive data
   - /etc

* prepare crontabs so that they are ready for the next reboot.

* switch idas1 & idas2 host names, along with IP addresses.

* reboot.

* update crontabs.

* update the mahchine labels.

* verify that NFS exports & cron jobs are working as expected.

* if needed, re-run failed jobs related to data archive.

* move the disk array to the computer room.


Replacement
============
@@ I will need help with removal & installation of disk arrays. @@

* on idas2 host (previously idas1), put ZFS pool1 and pool2 in offline mode.

* remove the disks of both pools from the idas1 disk array.
   - label them with POOL NAME, DISK NUMBER as seen by OS, and the SLOT in
     the array.
     ^^
      `+-- Need to research more about removing, adding disks to
           a ZFS pool; ask Miranda H-O if she has notes of her
           attempts.

* remove the old disk array.

* install the new disk array.

* install pool1 drives in order. Put the pool in online mode.

* install 6TB drives in pool2 to see if all the drives are recognized by the
  OS.
   - if YES, create a new ZFS pool "pool3" and add the new drives to the
     pool.
      -- then, copy data from ZFS pool "pool2" on idas1 to idas2 to "pool3".
      --- then, rename "pool3" to "pool2" (may need to destroy "pool2").