how to increase the size of LVM which used by multipathd...
 

we r using RHEL 5. mount the SAN Partition in RHEL5 using multipathd.
LUN size was 5 GB. now the SAN Admin increased that LUN to 10 GB. but its not updated in RHEL5. when we put fdisk -l the size was only 5 GB.
i want to know how to update that Size and how to increase that VG from 5 GB to 15 GB without affecting the data.

Items to review:

• To add a physical volume to a VG, see the manpages for vgextend(8).
• To add size to a LV, see the manpages for lvextend(8).
• To grow a filesystem to fill up a resized LV, see the filesystem's documentation. (On RHEL4, ext2online(8) was used for ext2 filesystems; not sure off the top of my head for RHEL5.)

Hello,

You can consult this easy to read Guide to LVM. It contains all the commands needed, examples and much more.

Kind regards,

Eric

we increased the size in the Same lun. after restartign the server it gets reflected in that disk. but pvdisplay shows only 4gb. now how to increase the vg. is it possible to increase the vg.
[root@domclust2 ~]# fdisk -l
Disk /dev/sda: 36.4 GB, 36401479680 bytes
255 heads, 63 sectors/track, 4425 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sda1 * 1 13 104391 83 Linux
/dev/sda2 14 4425 35439390 8e Linux LVM

Disk /dev/sdb: 15.0 GB, 15032385536 bytes
64 heads, 32 sectors/track, 14336 cylinders
Units = cylinders of 2048 * 512 = 1048576 bytes

Disk /dev/sdb doesn't contain a valid partition table

Disk /dev/sdc: 15.0 GB, 15032385536 bytes
64 heads, 32 sectors/track, 14336 cylinders
Units = cylinders of 2048 * 512 = 1048576 bytes

Disk /dev/sdc doesn't contain a valid partition table

Disk /dev/dm-2: 15.0 GB, 15032385536 bytes
255 heads, 63 sectors/track, 1827 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/dm-2 doesn't contain a valid partition table

Hello,

Can you (re) post output of following commands, but include them in CODE tags please (the # mark on the icon bar in the editor window).
That way we get a clear (and readable) view of your current setup.

Kind regards,

Eric

thanks to everyone the problem was solved when we use the pvresize the new size gets updated in the PV and VG. then we extend the lv by using lvextend.

Good job! Mark your thread as SOLVED using the thread tools please.

Kind regards,

Eric

Hey!

I didn't try it yet and wonder... Did this operation reflected any of your data residing your physical volume with the old lun size?

And i'm wondering 1 thing more... Why did you find increasing lun size at the storage level usefull? Is it an ASM disk? I don't find it usefull to change the size at the storage level because if you would need to decrease the size, you will see that very dangerous...

Sorry for my curiousness :)

our data is ok. nothing lost. may be if we decrease the size our will be lost. but sofar in our test environment we didnt try decreasing the size of a LUN.

sorry i really wonder why is this method usefull...