Description of problem:
some SANs allow online LUN extension. Using that in RHEV currently means some manual work:
1) on all hosts, rescan iscsi disks: echo "1" > /sys/block/sdX/device/rescan
2) on all hosts, resize multipathed device: multipathd -k'resize map dm-Y'
3) on SPM, run: pvresize /dev/dm-Y
4) let engine know current storage size (can be done by force-switching engine)
Version-Release number of selected component (if applicable):
encountered on 3.2
Steps to Reproduce:
1. extend online backing iscsi LUN
2. try to make use of the new space in RHEV-M
steps to extend multipathed device are from RHEL docs: https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/DM_Multipath/MPIO_admin-troubleshoot.html#online_device_resize
Yes. I didn't notice it while reporting so sorry for the noise.
*** This bug has been marked as a duplicate of bug 609689 ***