Re: imapsync's --maxage flag

[David Emmerich <dpemmerich@driftwood.eiu.edu>]

Hi John,

I used the --maxage option with great success during our migration.  It was awhile ago when we did it in bulk, and I know several versions have been released since then, but I don't recall any issues when we did it.  I have used it off and on since then with success too, but that was with single accounts that needed mail from the last x days restored, so I restored to a new account then imapsynced the mail over for them.

Anyway, just my 2 cents.

David Emmerich
Network Specialist II - ITS Systems Administration
Eastern Illinois University

----- Original Message -----
From: "John Fulton" <fultonj@lafayette.edu>
To: zimbra-hied-admins@sfu.ca
Sent: Tuesday, September 30, 2008 5:25:25 PM GMT -06:00 US/Canada Central
Subject: imapsync's --maxage flag

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1


I need to imapsync 5,000 accounts totaling 800G of mail. Has anyone used
imapsync's --maxage flag to speed up an imapsync? If so, any problems?

If you're going to have repeated runs on imapsync it seems that you can
shrink the time for each sync by setting --maxage to the number of days
between the start and end of the previous imapsync.

I did an early test. It took me 50 minutes to imapsync 450M of mail even
if run repeatedly every hour. However if I run a second time with
"--maxage 1", i.e. sync only messages from the last day, then it took
only 3 minutes. This is only for a single user but I expect this trick
to ease my migration.

I expect the first sync to take a long time: let's assume n days. After
that I would sync again but with maxage at n and then I expect n to
decrease for each call.

imapsync
imapsync --maxage n
imapsync --maxage n=time(previous_call)
...
imapsync --maxage k

Finally k would be either the outage window OR the time users must wait
for the last set of messages between k and today for all of their mail
to finally be cut over after go live. You would have a good idea of what
k would be after repeated runs with no change in n.

Has anyone tried this?

  John
- --
John Fulton, Linux Administrator, Lafayette College ITS
610-330-5650, Pardee Hall Room 11, Easton PA 18042-1775
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.6 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iD8DBQFI4qdVNZmEpbCkXmERAhqPAJ41vRfeYt7a/mNsaJ8+OV1MetZaIQCeKbQC
JwPQnezZf6E4vovnA8uj6S4=
=F6a2
-----END PGP SIGNATURE-----