Raid 5 on 6 disks

[roycrom]

I am running solaris 9. I have 6 x 18Gb disks that I want to configure as RAID 5.

I have created and initialized my disks named disk01 to disk06 and they are all in the rootdg disk group.

I ran the command

vxassist maxsize layout=raid5 disk01 disk02 disk03 disk04 disk05 disk06

which gave me this output

Maximum volume size: 141416448 (69051Mb)

I'm losing a third of my disk space here where I only expected a loss of 1/6th due to the parity checking.

Can anybody tell me what I'm doing wrong? Thanks.

------------------------------------------
Somethings come from nothing, nothing seems to come from somethings - SFA - Guerilla

roycrom

 

[alarnold]

You are doing nothing wrong. RAID 5 takes about 1/3 for of the usable storage space for redundancy. I also was shocked at the space it required. The nice thing about RAID 5, if one of your hard drives dies, it can rebuild your valuable information of the remaining drives.

Hope this helps, Al

 

[alarnold]

You are doing nothing wrong. RAID 5 takes about 1/3 for of the usable storage space for redundancy. I also was shocked at the space it required. The nice thing about RAID 5, if one of your hard drives dies, it can rebuild your valuable information off the remaining drives.

Hope this helps, Al