extending LVM on SW RAID
We have 2 160GB disks in software raid1 with 3 partitions - so we have
md0 (root fs), md1 (swap) and md2 (PV for LVM). One disk has failed
and because will need more space in near future I'm thinking of buying
2 bigger disks. The question is how to resize the raid & lvm.
In some FAQ I have found that I can resize the last partition in fdisk
and then run mdadm --grow on the md2. There is pvresize command for
LVM, but is it safe to use it? And last question is from where to get
this command, because it is not in LVM 2.01 in sarge and only in etch.
Another possibility would be to create another partition & md3 on the
free space of bigger disks and use it as second PV in LVM. But as far
as I know kernel's read optimization for RAID1 (choosing from which
disk read which data) assumes only one md device on each disk, so that
would hurt performance even more than my todays' 3 md devices
(although md0 and md1 are not used much).