Creating LVM on a EMC Symmetric SAN

[Nath_3]

Hi,

We have a server with 21 vgs created already. I was asked to create one more Vg with 320 LVs of 2 GB each. SAN team has allocated 550 Gb i.e., 8x68Gb luns for a server.
Now I am supposed to create a vg with 250 lvs. Out of these 22 VGs, 18 Vgs donot have space to create the any Lvs
i have only 4 Vgs how can i create the these lvs across the 4 vgs.
Please correct me if there are any steps or commands missing.

Steps:
1. ioscan -funC disk
2. insf
3. pvcreate -f /dev/rdsk/c#t#d# (All 8 luns)
4. mkdir -p /dev/
5. mknod /dev//group -c 64 minor number.
6. vgcreate -s /dev/
7. lvcreate -L 2001 i 8 I 64 -A n -n


I am confused on how can i create the vgs across the 4 vgs. Pls help me on this. Also,pls fill me on this.

Thanks

[Suraj K Sankari · Accepted solution]

Hi,

Your steps are looks ok but didn't understand about this line.

>I am confused on how can i create the vgs across the 4 vgs

vgs across the 4vgs ? means please clear

Suraj

[Nath_3]

Thanks
I have to create the lvs across the 4 vgs How can i do. I need help on the script.

Thanks

[Ganesan R]

Hi Nath,

If the HP-UX version is 11.11 or 11.23, then you cannot create more than 255 logical volumes within a VG. But in 11.31 you can have more than 255.

Other thing is, you have only 550GB of disk space and you want to create logical volumes of 2GB each. So you can create 255LV's*2GB=510GB. You will be wasting 40GB if you add all disks to single VG.

you can assing 7Luns to one VG, and assign the remaining 1Luns to another new VG or existing VG and create the logical volumes on it.

Your steps looking one. but you missed out to add the disks to the newly created vg.

After vgcreate you have to add the disk using vgextend command. command syntax would be #vgextend pv1 pv2 ....

>>lvcreate -L 2001 i 8 I 64 -A n -n <<

Do you really need striping on the logical volumes? you specified i 8 I 64

Why you use the option -A n ? Then it will not backup the configuration.