[root@wuc212 ~]# pvcreate /dev/hdd1
  Physical volume "/dev/hdd1" successfully created
[root@wuc212 ~]# pvcreate /dev/hdb1
  Physical volume "/dev/hdb1" successfully created
[root@wuc212 ~]# vgextend simulation /dev/hdd1 /dev/hdb1
  Volume group "simulation" successfully extended

[root@wuc212 ~]# e2fsck -f /dev/simulation/data
e2fsck 1.38 (30-Jun-2005)
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
/dev/simulation/data: 615910/16646144 files (1.5% non-contiguous), 3218755/16646144 blocks
[root@wuc212 ~]# resize2fs -p /dev/simulation/data
resize2fs 1.38 (30-Jun-2005)
Resizing the filesystem on /dev/simulation/data to 55721984 (4k) blocks.
Begin pass 1 (max = 1193)
Extending the inode table     XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
The filesystem on /dev/simulation/data is now 55721984 blocks long.

[root@wuc212 ~]# e2fsck -f /dev/simulation/data
e2fsck 1.38 (30-Jun-2005)
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
/dev/simulation/data: 615910/55738368 files (1.5% non-contiguous), 4444831/55721984 blocks