Adding LUNs

[f. halili]

Do you need to reboot the system, or be in single user mode to create a LUN???

Will there be a problem in doing this when system is up ( assuming this a production box) ???

[Andreas Voss · Accepted solution]

Hi,

you don't say which storage system you wnat to add a LUN but if you have an AutoRAID there is no requirement for rebooting.
You can add a LUN at the running system.
If you doing it with arraycfg you have to create the new device files with:
ioscan -fn disk
insf
Or you can use SAm (which creates the device files automatically)

Greetings

Andrew

[f. halili]

thanks for all the info......

[Maarten van Maanen]

Hi,

Wonderous world. Am expanding some volumes on a HP AutoRAID just now and doing it live.

Step 1 is creating LUN.
Create two if you have two RAID-controllers and switch them to increase performance.

Create LUN:
arraycfg -L 5 -a 5000 arrayID
-L = LUN-no -a = size in Mb

Create device-files:
insf -C disk

Check them with ioscan:
ioscan -fnC disk

Prepare them for LVM:
pvcreate -f /dev/rdsk/CxTyDz
x, y z from the device files creating

Including them in the VG you want them:
lvextend /dev/vgxx /dev/dsk/CxTyDz /dev/dsk/Cx2TyxDz3

Do this again with device files switched to created alternate links on the AutoRAID so each disk use the other controller for backup.

Check the VG with vgdisplay -v (or look in /etc/lvmtab)

umount the LV you want to extend:
umount /Lvname

Extend the LV to the required size:
lvextend -L (size) /dev/vgxx/lvolxx

Create the filesystem on the extra space:
extendfs -F jfs or vxfx /dev/vgxx/rlvolxx

Mount de LV again and voila, you'r ready to go. If you can bring the LV down because it's in use you can check the actual users with fuser and then kill them with fuser -cu.

Success,

Maarten van Maanen
Netherlands