| 2009-03-19 15:47:19 |
Ken Simon |
multipath-tools: statusexplanation |
|
This bug's gone pretty much unnoticed I guess, but I'm experiencing the same issue. I'm scheduling downtime for next thursday (unfortunately this is a production machine) to try out some different LVM configurations, to make sure I can get it to reliably reboot with LVM scanning the multipath nodes, instead of the raw (sd*) device nodes.
Here's the configuration I'm using and expecting to work:
lvm.conf:
devices {
dir="/dev"
scan="/dev"
filter=["a|/dev/mapper/mpath.*|", "r|.*|"]
cache="/etc/lvm/.cache"
write_cache_state=1
types=["device-mapper", 1]
sysfs_scan=1
md_component_detection=1
}
Note that "types=" contains device-mapper types. IIRC this is not by default in Ubuntu, but is required for multipath support.
Also note that "filter=" is telling LVM to only scan for /dev/mapper/mpath*. This will make sure that LVM is only scanning for devices in /dev/mapper that begin with mpath. To get multipath to make devices with this prefix, edit multipath.conf:
defaults {
...
user_friendly_names yes #names the devices mpath0 - mpath<n>
...
}
Or, optionally configure aliases for each multipath, and have them begin with "mpath".
These changes *should* force LVM to only ever look at /dev/mapper, and for multipath devices in particular, for PV's. If you use LVM for more than just mpio, change the filter line in lvm.conf to something like:
filter=["a|/dev/mapper/mpath.*|", "a|^/dev/sda1$|", "a|^/dev/sdb1$|", "r|.*|"]
This will add /dev/sda1 and /dev/sdb1 in addition to the mpio devices.
I'll update this bug next thursday to say whether it works or not after a reboot. |
|
