Hello there!

I have a a slight issue updating and extending a lvm partition on a server which we don't want to reboot..

The thing is that this volume is shared through a SAN. The SAN part have been updated with another 25gb, but it does not show up when I run pvscan:

pvscan sends me this:
PV /dev/sda1 VG VolGroup01 lvm2 [150.00 GB / 0 free]

and it "should" now show 150.00 GB / 25.00 GB free

Apparently it shows up with no delay on m$.

What am I missing?

BR

Just sayin, Im not that good with lvm - this might be really easy :-)

You probably have the disk (/dev/sda) enlarged, but the partition table still has claimed 150 GB for /dev/sda1 (the first partition);
Somehow this partition ought to be enlarged using this new free space, so that the PV is showing the free space that can be allocated by the VG and thus LV

You could try "vgchange --refresh and vg name", cannot guarantee that it will sole your problem, but it's worth a try.

If you have problems with fs space and you will need to fix it, assign new disk from sun and assign it to the vg and extend you fs's, this is the fastest way, if there is a real problem and you need to fix it quick.

Thanks for you reply!

Adding '--refresh' is not acceptable/possible with at least my version of vgchange.

Somehow I get the feeling your 'fast solution' is basically what I started up with and intended to do; we assigned new space from SAN at first, but I expected the resized space to show up when I run pvscan, but perhaps it does not work that way?
You wrote "..assign it to the vg and extend your fs.." makes me wonder, how do I assign it to the vg?

BR

Wel, this is how LVM works:

PV[s] (Physical Volumes) > VG (Volume Groups) > LV (Logical Volumes) > Filesystem

After you assign the disk from SAN:

-fdisk -l (you will see your new disk here line /dev/sdax and that it contains no valid partition table
-using fdisk you will create a new partition table like:

Ex:

fdisk /dev/sdbx

Command (m for help): p

Disk /dev/sdb: 293.3 GB, 293389467648 bytes
255 heads, 63 sectors/track, 35669 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System

Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-35669, default 1):
Using default value 1
Last cylinder or +size or +sizeM or +sizeK (1-35669, default 35669):
Using default value 35669

Command (m for help): p

Disk /dev/sdb: 293.3 GB, 293389467648 bytes
255 heads, 63 sectors/track, 35669 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sdbx 1 35669 286511211 83 Linux

while you are in fdisk do:

Command (m for help): t
Selected partition 1
Hex code (type L to list codes): 8e
Changed system type of partition 1 to 8e (Linux LVM)

Command (m for help): p

Disk /dev/sdb: 293.3 GB, 293389467648 bytes
255 heads, 63 sectors/track, 35669 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sdbx 1 35669 286511211 8e Linux LVM

Command (m for help):

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.

After the disk is partitioned for LVM you need to:

pvcreate /dev/sdbx

Physical volume "/dev/sdbx" successfully created

After you creted the PV, you will need to exteng your VG:

vgextend (vg_name) /dev/sdbx

-now you can check your VG size: vgdisplay

Now you can exteng your LV and filesystem:

lvextend -L +15G /dev/vg_name/your_name_lv

resize2fs /dev/vg_name/your_name_lv

Now you can do a df -h on your filesystem to see your new size

Hope it helps

Gr2600 tells you exactly what needs to be done; Excellent roundup!

Is almost 100% correct, with the addition that a PV is a partition.

So, you increased your physical disk. That disk contains a partition table. Currently you'll have a partition table that is not covering 100% of the disk, as it has been enlarged. So, you'll first need to update the partition table, so that it covers this new free space as well. (That's done with fdisk as Gr2600 shows; cfdisk is also possible as are other tools).

After the partition table has been updated, you'll not yet see the free space, although you should now see the free space in your VG; taking that you increased the partition that was already assigned to your PV, and thus the VG. Now that the PV is increased, you can expand the LV after which you can increase the FS (assuming you have a filesystem that supports resizing).

Just follow Gr2600's instructions and you should be set.