MBOX-Line: From dot at dotat.at  Mon Aug 27 03:31:20 2007
To: imap-protocol@u.washington.edu
From: Tony Finch <dot@dotat.at>
Date: Fri Jun  8 12:34:40 2018
Subject: [Imap-protocol] Private FETCH items
In-Reply-To: <46CD9A95.4030001@andrew.cmu.edu>
References: <46CC88EE.5040500@andrew.cmu.edu>
	<22D7E33A-FD12-4B76-8240-89A4690A03B6@orthanc.ca>
	<46CD9A95.4030001@andrew.cmu.edu>
Message-ID: <Pine.LNX.4.64.0708271125570.16524@hermes-2.csi.cam.ac.uk>

On Thu, 23 Aug 2007, Ken Murchison wrote:
>
> I probably wasn't clear in the use case.  Cyrus now has the ability to
> replicate a mailstore in near realtime.  Several sites (including CMU in the
> near future) are using this to have redundant mailstores in case of a hardware
> failure.  Rather than create a new tool or protocol to verify the consistency
> of the mailstore pairs, extending IMAP with a couple of new FETCH items seems
> like a reasonable thing to do.

I should note that the MD5 replica consistency check has been very useful
in finding lurking bugs in the code, both the original version and across
versions as the code has evolved. It's also good for discovering bit-
smashing hardware failures that haven't (yet) affected lower levels of the
os/driver/raid stack. You can only be sure of data integrity if you test
it end-to-end.

Tony.
-- 
f.a.n.finch  <dot@dotat.at>  http://dotat.at/
IRISH SEA: SOUTHERLY, BACKING NORTHEASTERLY FOR A TIME, 3 OR 4. SLIGHT OR
MODERATE. SHOWERS. MODERATE OR GOOD, OCCASIONALLY POOR.

