Windows – How to use new disk space after extend attached SAN disk

This is what I have used for systems with dm-multipath and LVM; modify as needed:

1) Increase size of LUN in SAN
2) Check with "multipath -ll" which devices belong to said LUN
3) For each device above, do "echo 1 > /sys/block/sdX/device/rescan"
4) Go to multipath command line with "multipathd -k"
5) For each device, do "del path sdX", "add path sdX" while hoping that
the multipathing functionality works as advertised and fails over properly.
6) "resize map multipath-map-name"
7) Exit multipath command line (Ctrl-D), check with "multipath -ll" that
new size is seen.
8) pvresize, lvextend, resize2fs
9) Profit!

This works as of RHEL 5.3.

I am pretty sure this is a kinown issue with Windows Server 2000. It didn't support disks that changed size without a dismount/remount. We hit this issue a number of times. Typically the way you solve this is with thin provisioining/storage virtualization. I.e. you create a partition that says it is 2TB but is only backed by 500GB of storage. Then behind the scenes you can add storage over time either manually or autoamtically up to the 2TB limit without requiring a reboot. Once you go beyond that you will have to reboot the system.

Worked for us back when this was an issue. Alternative is to upgrade the OS. I seem to remember Server 2003 deals with this much better.

Thanks,

Chris