Cannot reactivate RAID-5 volume: The size of the plex member is invalid
- by Ian Boyd
We had a 3-drive Windows Server 2008 R2 RAID-5 fail (operating in redundancy mode):
WDC 1 TB
WDC 1 TB
WDC 1 TB
We removed the failed hard drive, and put a WDC 1 TB drive (that we had standing by) into the machine.
When launched, Disk Manager, asked permission to "initialize" the disk as either:
Master Boot Record (MBR)
Guid Partition Table (GPT)
We initialized the disk as GPT, converted it to dynamic, and tried to use the Repair Volume command - except it was greyed out. (which is a terrifying thing on a failed production server hosting 3 virtual servers)
i tried from the diskpart command line tool. First we look for our RAID-5 volume that is in Failed Rd mode:
DISKPART> list volume
Volume ### Ltr Label Fs Type Size Status Info
---------- --- ----------- ----- ---------- ------- --------- --------
Volume 0 E VMs (Raid5) NTFS RAID-5 1863 GB Failed Rd
Volume 1 D DVD-ROM 0 B No Media
Volume 2 System Rese NTFS Partition 100 MB Healthy System
Volume 3 C NTFS Partition 1862 GB Healthy Boot
There, Volume 0. Make that our active context:
DISKPART> select volume 0
Volume 0 is the selected volume.
Now we need to find the disk we will be repairing the volume with:
DISKPART> list disk
Disk ### Status Size Free Dyn Gpt
-------- ------------- ------- ------- --- ---
Disk 0 Online 931 GB 0 B *
Disk 1 Online 931 GB 931 GB *
Disk 2 Online 1863 GB 0 B
Disk 3 Online 931 GB 0 B *
Disk M0 Missing 0 B 0 B *
The disk with 931 GB free, Disk 1. Now we just need to repair the volume:
DISKPART> repair disk=1
Virtual Disk Service error:
The size of the plex member is invalid.
