Problem: LVM Warnings About Duplicate PVs with Multipath Tools

Problem

When using multipath devices (ie FC-SAN) LVM complains about duplicate physical volumes (PV):

Found duplicate PV GDjTZf7Y03GJHjteqOwrye2dcSCjdaUi: using /dev/dm-5 not /dev/sdd
Found duplicate PV GDjTZf7Y03GJHjteqOwrye2dcSCjdaUi: using /dev/emcpowerb not /dev/sde
Found duplicate PV GDjTZf7Y03GJHjteqOwrye2dcSCjdaUi: using /dev/sddlmab not /dev/sdf

Solution

Create a filter for your multipathed devices in the /etc/lvm.conf file. Disable all other “filter=” lines::
filter = [ "r/block/", "r/disk/", "r/sd.*/", "a/.*/" ]

Explanation of this filter line:
This filter will remove all devices having “block”, “disk” in there access path. Additionally remove all devices starting with “sd” followed by any other characters.
It will add all other devices (ie mutlipath devices nodes)

References

RedHat: LVM filtering.
RedHat: Duplicate PVs