[CentOS] LVM lvresize/lvextend requires some space in /etc to grow a logical volume?

Mon Sep 19 23:15:09 UTC 2011
Johnny Tan <johnnydtan at gmail.com>

Side note:

In CentOS-6, I noticed a new option in lvresize / lvextend:

       -r, --resizefs
              Resize underlying filesystem together with the logical
volume using
              fsadm(8).

Nice. Two steps (lvresize and resize2fs) can now be combined into one!
Works great.

But that has nothing to do with my question, just thought I'd share
the discovery.

==

Anyway, here's the real issue with LVM, at least in CentOS-6:

[root at jttest ~]# df
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/mapper/vg_main-lv_root
                       1548144   1548144         0 100% /

[root at jttest ~]# lvextend -L 2G /dev/vg_main/lv_root
  /etc/lvm/archive/.lvm_jttest.pp.local_5523_51321310: write error
failed: No space left on device
  Volume group "vg_main" metadata archive failed.
  /etc/lvm/cache/.cache.tmp: write error failed: No space left on device

So I can't extend a logical volume if there's no space in /etc?

Granted, I only need to delete like 2k worth of files in the same
logical volume as /etc to make the above work, but I don't recall
lvresize or lvextend requiring space in /etc to do a resize. Has this
always been the case? I don't have any 5.x servers handy to test this
with. Can anyone verify?

If this is new, this seems less-than-ideal. /etc itself rarely fills
up, so, in theory, I could make it its own LV, but that's even less
ideal. For now, I'll stick to deleting just enough to do the
extend/resize.

johnny