Extend iSCSI storage
Stop LV on all nodes except one
Rescan iSCSI node on one host
# iscsiadm -m node -R
Resize PV
# pvresize /dev/<disk/part>
Execute vgs and verify extended size visible as free space
Extend LV
# lvextend -l +100%FREE /dev/<vg>/<lv>
On all other nodes run
# iscsiadm -m node -R
# pvscan