Linux – How to map iostat device names to LVM /dev/mapper/XXX names

iostatlinuxlvmmount

mount shows mount devices like:

/dev/mapper/VolGroup01-LogVol00 on /var type ext3 (rw)

/dev/mapper/VolGrp_backups-backups on /mnt/backups type ext3 (rw)

but

iostat uses dm- notation. like dm-0, dm-1 and so on.

Where can I find a way to know which is which?

ls -l /dev/mapper/*, the device minor number (field 6 of what ls -l outputs) corresponds to the number in dm-\d+.

Check out /etc/lvm/lvm.conf - you'll need to edit it and adjust the filter config.

Basically, LVM scans all the block devices in your system and is finding /dev/sdX before /dev/mdX.

If you edit lvm.conf and add something like

filter =  [ "a/md/", "r/.*/" ]

it will only scan /dev/mdX devices.

Do'h! Just a careless mistake on my part. I just ran partprobe and then update-initramfs and now everything's peachy.