how to setup Disk Mirror on SUN V880

[100mbs]

I have a V880 and i want to mirror the OS drives. They are two 146GB Fiber Channel Drives.

Dont these servers have Hardware RAID controllers or do i need to use my Veritas Volume Manager to create the RAID?

Also what is the difference between concatenated volume and Creating a mirror?

 

[Mike042]

Dont these servers have Hardware RAID controllers or do i need to use my Veritas Volume Manager to create the RAID?
Some of the SunFire servers have H/W Raid (eg V440) and some do not (eg V1280). Check the 'spec' on the Sun website to be sure. (If a feature is not mentioned then it probably doesn't exist - is a good rule of thumb!)

Solaris 8 has Solstice DiskSuite (SDS) that can be downloaded or installed from 'Solaris 8 Software 2 of 2' CD. Solaris 10 has Solaris Volume Manager (SVM) in-built. Both are S/W Raid packages.

Also what is the difference between concatenated volume and Creating a mirror?
I think a 'concatenated volume' is a 'Stripe' or RAID 0 (which is not really RAID at all because the 'R' stands for Redundant and there is no redundancy with this!). It effectively doubles the disk capacity of a single disk, but halves the mean-time-between-failures, because the second disk is 'bolted' onto the end of the first disk. A 'mirror' effectively halves the disk capacity of both disks, because a complete copy of one disk is maintained on the other.


I hope that helps.

Mike

 

[elgrandeperro]

I don't believe and v880 has onboard raid.

I think you want the difference between a concat device and a striped device. Concat as stated just bolts together disk pieces and a stripe device lays out blocks across the disks. Stripes are faster. Both cannot be rebuilt with the failure of a single device, they must be restored.

A mirror is a logical device that replicates 2 volumes. If the volumes don't use the same phycical device, then loss of one device will only require rebuilding the bad device and reattaching the mirror.

Sorry if some my naming is wonky, I've admin'ed both Disksuite/SVM and Veritas so I get confused on their conventions.

To mirror the OS disks, I typically only uses SVM since it requires less complexity and is supported and works fine.

 

[jimmies]

Hi
Agree SVM is easy to use for mirroring.
Stripping will be the best to use for performance that will reduce the I/O wait and for redundancy (RAID 0+1) if you lose one disk you don't need to resync the whole side of the mirror only the failed stripe
Hope this will help

 

[ohnowhathaveidone]

Hi, you want to mirror partitions that cannot be unmounted. You need to format the mirror disk exactly like the primary disk.
make a copy of your /etc/vfstab and /etc/system (this may get you out of jail later)
Create a concat stripe of the partetion on the primary disk.
Create a mirror and drop the concat stripe into the mirror. You now have a one way mirror. VERY IMPORTANT - If you are mirroring the root / filesystem, make the mirror bootable. metaroot d??
Stop all updated to the file system lockfs -fa
Reboot
create a concat stripe of the secondary mirror partition and drop it into the mirror. IMPORTANT, keep an eye on the mirror syncing. DO NOT INTERRUPT THE SYNC. (I learned this the hard way.)
See the following for details....

http://www.sun.com/bigadmin/content/submitted/svm_mirroring.jsp

http://slacksite.com/solaris/disksuite/disksuite.php