On 12/14/18 7:57 AM, Rich Freeman wrote:
Yes. At least by default LVM is going to scan all your drives looking
for LVM PVs and will identify them regardless of what device they are on,
as long as the device gets scanned.
I wouldn't be surprised if LVM didn't scan all block devices.
I think LVM always looks for /dev/sd* and /dev/hd* by default. (At
least all the times I've used it.)
I can't say the same for things like /dev/mpath* or other more
intriguing block devices.
Yes, in general. The only time you might have an issue is if you use
something more exotic that creates a block device that might not get
scanned by default, but I believe that is just a configuration fix.
So, if you're using iSCSI or something maybe you might need to do a
little work.
Yes, there should be an entry of devices to scan and an entry of black
listed devices. I think this is in /etc/lvm.conf or something like
that. (It's been a number of years since I've changed it.)
Bog standard PCs shouldn't need to worry about this. Servers or things
with more exotic storage may have a problem in that the default might
not work for them.
ProTip: Be careful if you are using LVM on multipath devices. You want
to make sure that LVM is scanning the multipath device and not the
member path devices. LVM will happily use the first one that it finds.
So scan order and / or black listing is important.
