In short: you can't.
Long version: The different sd<x> devices represent different views on the same disk over different paths (hence *multi*-path). Usually you don't use these (because every one of them represents one single connection to the disk) but the multipath-device.
Your actual problem probably is that the additional devices mess up your LVM2 configuration. This is taken care of the following way:
The first layer to deal with the LUNs from SAN is the multipath-software. Make sure you give meaningful alias names in "/etc/multipath.conf". That makes administration a lot easier. I use <vgname>pv<nr> (like: "myvgpv01", "myvgpv02", etc.) for the disks. "/etc/multipath.conf" looks like:
[...]
multipaths {
#----------------- [dbvg Start] ----------------------
multipath {
wwid 360050768018200878000000000000108
alias dbvgpv01
}
multipath {
wwid 360050768018200878000000000000140
alias dbvgpv02
}
#----------------- [dbvg End] -------------------------
#----------------- [appvg Start] ----------------------
multipath {
wwid 360050768018200878000000000000149
alias appvgpv01
}
#----------------- [appvg End] ------------------------
}
[...]
This will create these disk aliases and the respective udev rules should create device mappings in "/dev/mpath" like this:
root@host # ls -l /dev/mpath
total 0
lrwxrwxrwx 1 root root 8 Jun 20 12:31 dbvgpv01 -> ../dm-13
lrwxrwxrwx 1 root root 8 Jun 20 12:31 dbvgpv01p1 -> ../dm-21
lrwxrwxrwx 1 root root 8 Jun 20 12:31 dbvgpv02 -> ../dm-14
lrwxrwxrwx 1 root root 8 Jun 20 12:31 dbvgpv02p1 -> ../dm-20
lrwxrwxrwx 1 root root 8 Jun 20 12:31 appvgpv01 -> ../dm-11
lrwxrwxrwx 1 root root 8 Jun 20 12:31 appvgpv01p1 -> ../dm-17
[...]
After getting this to work you have to configure the LVM2 by creating a filter-rule and a directory to look for possible PVs. The configuration file is "/etc/lvm/lvm.conf":
[...]
devices {
[...]
# An array of directories that contain the device nodes you wish
# to use with LVM2. "/dev" is for the local disk(s) /dev/sda, /dev/sdb,
# etc., "/dev/mpath" is for the SAN disks
scan = [ "/dev", "/dev/mpath" ]
# filter rules are basically regexps. "a|" means "accept", "r|" means "remove".
# The rules in detail:
# "r/.*/" removes every device not explicitly allowed by the rules before
#
# "a|vg[0-9]*pv[0-9]*|" my VG names always end in "vg", sometimes followed by a number
# allow everything ending in "vg" or "vg<nr>" followed by "pv<nr>" like
# "appvgpv01" or "db5vgp03", etc.
#
# "a|sd[ab]$|", "a|sd[ab][1-9]*$|" allows "/dev/sda" or "/dev/sdb",
# both optionally followed by a number (/dev/sda1), but NOT a
# character. This filters out "/dev/sdaa" and similar devices.
filter = [ "a|vg[0-9]*pv[0-9]*|", "a|sd[ab]$|", "a|sd[ab][1-9]*$|", "r/.*/" ]
[...]
}
You should by now be able to use "pvscan"/"vgscan" to find your VGs and LVM2 should exclusively make use of the multipath devices.
I hope this helps.
bakunin