Well it was time to add some space to my Media Server. I started with one 80GB for the OS and Music. Then added a 200GB for MythTV, but using mpeg2 fills up the drive fast. I had the foresight to use LVM so I could add room when needed. I was always running at 90% so I went and bought a new 160GB. This is what I did to install it.

IDE id’s go like this in Linux
hda Primary Master
hdb Primary Slave
hdc Secondary Master
hdd Secondary Slave

I added the 160GB drive to the Secondary Master

I created the partition with fdisk and changed the id (type) to 8e(LVM).
pvcreate /dev/hdc
This gave me and error saying that there was partitions on the selected drive. I had to run the following 2 commands to fix this.

dd if=/dev/zero of=/dev/hdc bs=1k count=1
blockdev –rereadpt /dev/hdc

I then ran the extend command, you will need to unmount the LVM first

umount /dev/VGforMyth/video

vgextend VGforMyth /dev/hdc video2

but this resulted in an error. After googling around I found I had to use the full path and not the link

vgextend VGforMyth /dev/ide/host0/bus1/target0/lun0/disc video2

You can find the full paths to your drives by doing a

ls -la /dev /hd*

You should see something similar after using the pvdisplay command

pvdisplay /dev/hdc

--- Physical volume ---
PV Name               /dev/ide/host0/bus1/target0/lun0/disc
VG Name               VGforMyth
PV Size               152.67 GB [320173056 secs] / NOT usable 64.19 MB [LVM: 137 KB]
PV#                   2
PV Status             available
Allocatable           yes
Cur LV                1
PE Size (KByte)       65536
Total PE              2441
Free PE               140
Allocated PE          2301
PV UUID               UH7WvH-KmdN-wYv1-Rrgz-dDju-MmdW-DBkLwn

Now to extend the existing LVM partition to use the extra space. This command will extend the partition and also extend the file system, and do a disk check.

e2fsadm -L+150G /dev/VGforMyth/video

This will take a few minutes to complete.
You are now ready to remount your LVM and you should see the extra space.

mount /dev/VGforMyth/video

df

Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/root             74897024  56218544  14873888  80% /
none                    257508         0    257508   0% /dev/shm
/dev/VGforMyth/video 340600744 159349488 163949752  50% /mnt/store