Adding disks to a new EMC AX100i at one of our offices, the fastest solution to expand the volume sizes was to upgrade them to Windows dynamic volumes and add the new disks to the volume. With no mirroring and plenty of server power, the use of the dynamic volumes was unlikely to impact performance but it would eliminate the need to transfer data off and on the EMC array. The dynamic volumes worked well at first, but turned out to be a bad idea that next time the attached servers were rebooted.

The iSCSI volumes were not attached when the servers started up and the “merge foreign disks” command needed to be run before the array could even be addressed by the server. The only way to keep the error from happening at every reboot was to remove the data, rebuild the volumes on the AX100i, and then move the data back - no time saved after all.

I expect that our use of the Microsoft iSCSI initiator had a lot to do with the problems. An iSCSI HBA would have made the volumes available earlier in the boot process and probably prevented the foreign disk status. Nonetheless, if we had wanted to spend the extra money on HBAs we probably would have bought a fibre channel array instead of iSCSI.

(A May 2005 article also mentions that loading Windows 2003 Server SP1 will result in crashes due to either Navisphere orPowerPath software.)

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