Hello, I am very new to LVM. Trying to extend a LV after I added a 4th disk in a HW RAID, but I don't have much luck. I am really hoping someone out there can help me. Here is my setup: [root@sk-nas ~]# fdisk /dev/cciss/c0d0 The number of cylinders for this disk is set to 53535. There is nothing wrong with that, but this is larger than 1024, and could in certain setups cause problems with: 1) software that runs at boot time (e.g., old versions of LILO) 2) booting and partitioning software from other OSs (e.g., DOS FDISK, OS/2 FDISK) Command (m for help): p Disk /dev/cciss/c0d0: 440.3 GB, 440345714688 bytes 255 heads, 63 sectors/track, 53535 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System /dev/cciss/c0d0p1 * 1 13 104391 83 Linux /dev/cciss/c0d0p2 14 35690 286575502+ 8e Linux LVM Command (m for help): As one can see /dev/cciss/c0d0 is now 440.3GB, which means that my 4th disk is "physically" seen in the array. so far so good. First issue, looks like the 4th disk in not seen by pvscan? [root@sk-nas ~]# pvscan PV /dev/cciss/c0d0p2 VG VolGroup00 lvm2 [273.28 GB / 0 free] Total: 1 [273.28 GB] / in use: 1 [273.28 GB] / in no VG: 0 [0 ] [root@sk-nas ~]# [root@sk-nas ~]# pvdisplay --- Physical volume --- PV Name /dev/cciss/c0d0p2 VG Name VolGroup00 PV Size 273.30 GB / not usable 18.89 MB Allocatable yes (but full) PE Size (KByte) 32768 Total PE 8745 Free PE 0 Allocated PE 8745 PV UUID 07qmA3-5eD9-klBa-OzWp-XDz1-pUvX-KGXAji [root@sk-nas ~]# What should I do, looks like my first disk is not seen by lvm? Thanks! Michael