Re: Are snapshots always consistent?

From: Jens Schweikhardt <schweikh_at_schweikhardt.net>
Date: Sat, 10 May 2003 16:41:32 +0200
Farid,

On Sat, May 10, 2003 at 12:55:37AM +0200, Farid Hajji wrote:
# I'm somewhat confused about snapshots.
# 
# Are snapshots (e.g. created with dump -L) supposed to
# be always in a consistent state?
# 
# What happens if a snapshot is taken, while background
# fsck is fixing a filesystem?

I'm no expert in file systems, but AFAIK the bg fsck mostly looks for
unreferenced blocks and puts them in the free block bitmap again, while
dump reads files (contents) and does not store block bitmaps and other
fs meta information. So, these operations should not interfere with
one another.

# If snapshots are not always consistent, how can one
# be sure about dump -L output? Is it better to take
# a snapshot first, fsck it, and _then_ dump the
# snapshot without -L (how?)?

The most appropriate place to ask this is probably freebsd-fs_at_ (in Cc:
and Reply-To:).

Regards,

	Jens
-- 
Jens Schweikhardt http://www.schweikhardt.net/
SIGSIG -- signature too long (core dumped)
Received on Sat May 10 2003 - 05:41:34 UTC

This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:37:07 UTC