Mirroring root volume group vg00 that spans 4 disks

[mike worrell]

We have a box that runs just to monitor our network and has network node manager/net metrix,etc on it. The box only has vg00 volume group on it and all the files for these products reside there. I have a 4.3gb and 3 - 2gb drives holding all the data. These fill up the left side of the Jamaica box. I have disks to go in the right side of the jamaica, extras that are the same size 1 - 4.3gb and 3 - 2gb.
Can you mirror when it spans over so many drives? I've always had just one drive that contained vg00 and just mirrored it to another drive.
???????
Thanks
Mike

[Marco Santerre]

Hi Mike,

The answer to your question is yes you can. You are mirroring at the Logical Volume level and therefore as long as you have the same quantity of space to mirror, there will be no problems whatsoever.

[A. Clay Stephenson]

You bet. Remember, you don't mirror at the drive level but rather at the logical volume level. The main requirement is that your mirrored boot disk must contain at least /, /stand, and primary swap - the layout of the other LVOL's is unimportant.
If this were me, I would allocate the mirrored LVOL's exactly as their counterparts on the other side of the JBOD.
I trust that the JBOD is actually split into two SCSI busses with different controllers.

[Jeff Schussele]

Hi Mike,

Absolutely, you can.
And since you're not going to be adding larger disks to the VG than were used during VG creation, then you won't encounter the max PE/PV problem that so many have faced. I would recommend that you *literally* mirror the drives physically i.e. put the 4Gb right next to the 4Gb in the Jamaica. Then add the disks to the VG in the same order that the original drives were added.
This is not mandatory, it's just very handy to know that the mirrors are right next to each other physically when you're troubleshooting drive trouble down the road.

Rgds,
Jeff

[Jeff Schussele]

Oh and I was going to add, as Clay as hinted, that the Jamaica enclosure can be driven by separate HBAs & doing so is highly desirable as you eliminate another SPOF (Single Point of Failure). So if you have a second HBA in this system, hook it up & use it for these new disks.

Rgds,
Jeff

[mike worrell]

thanks to all who replied
Have a great week
:-))