[tlug] Re: Mysterious LVM issue

[John Fremlin <john@example.com>]

Hi Birkir,

Good to hear you're not smarting from recent overwork.

"Birkir A. Barkarson" <birkirb@example.com> writes:

> In short I was copying about 216GB from one HD to another which had an
> LVM VG with exactly 216GB free. The copy (cp -a) went well and except
> for some bad data on the original nothing was reported. Once done though
> the LVM drive reported 0 bytes free, 216GB used.

Don't worry about LVM. Worry about your filesystem.

Were you perchance using root to do the cp? Perhaps you were running
into the "reserved blocks" issue, where you can set a portion of your
filesystem to be saved for root (and have it logically disappear from
df).

On ext2

tune2fs -m 0 /dev/mapper/america_main-store

to reserve nothing for root.

By default (mke2fs) a certain percentage is saved for root which is
annoying on large filesystems.

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