[Csync2] Sync of dissimilar hosts and dry run output deciphering

[Lars Ellenberg]

On Thu, Apr 17, 2008 at 09:57:56AM -0600, Dan Brown wrote:
> About four months ago I setup a server, copied quite a bit of data to it
> (around 60GB) and installed it in a remote collocation site about 600km away
> from our primary site.  At that point no csync2 initialization had been done
> on the host and due to various circumstances (telco problems, remote support
> problems, etc) the server didn't get initialized with csync2 until recently.
> 
> So in the meantime the primary server all of the data was originally copied
> off of has changed a bit and some of the files from the original copy are no
> longer there.  If it weren't so much data (about 77GB now) I'd just wipe out
> all of the data on the (currently) slave and re-sync it.  I've only setup
> replication like this locally before and never over a WAN link through the
> general internet.
> 
> I did an initial sync from the primary server to the secondary server and it
> updated quite a few GB of files.  I would like to update from the secondary
> server to the primary but it appears that it wants to re-add some files
> which have been deleted off of the primary server.  
> I'm assuming that since my conflict resolution is "auto left;" it wont
> actually re-add the files to the primary server (Demeter), but will it leave
> them in a dirty state when I run csync2 -xv on the secondary server
> (Persephone) until I manually remove them (all 5000!) or will it delete them
> locally automatically once it realizes that the master/primary server
> doesn't have them?
> 
> Once the secondary is sync'd with the primary I plan to turn the config into
> a master-master setup.

# wipe out old state
on both# rm /var/lib/csync2/*

# reinitialize
on both# csync2 -cIr /

# compare state, and mark dirty,
# using the side you want to use as sync source
only on source# csync2 -TIUX /

# sanity check
on source# csync2 -M
on source# csync2 -udv

# actually sync it
on source# csync2 -uv

-----------------
# other possibility:

# wipe out old state
on both# rm /var/lib/csync2/*

on source# rsync -Pavz --delete sourcedir/ target:targetdir/

# reinitialize csync2
on both# csync2 -cIr /

# compare state, and mark dirty,
# using the side you want to use as sync source
only on source# csync2 -TIUX /

now, csync2 -M should report nothing.

-- 
: Lars Ellenberg                            Tel +43-1-8178292-55 :
: LINBIT Information Technologies GmbH      Fax +43-1-8178292-82 :
: Vivenotgasse 48, A-1120 Vienna/Europe    http://www.linbit.com :