We run our cyrus 2.4 murder with deduplication switched on. Generally speaking this works well, but every so often user's complain about receiving duplicate messages. We've been taking a look at our delivery logs and our delivery db and it does seem to sometimes behave oddly e.g a series of messages gets delivered with the same Message-ID and if dump deliver.db we can see this sort of thing: id: <E4Aa6n7XGPzsf%2FKcSmgv9w%3D%3D@xxxxxxxxxxxxxxx> to: user.xxxxxxxx at: 1411970492 uid: 24022 id: <E4Aa6n7XGPzsf%2FKcSmgv9w%3D%3D@xxxxxxxxxxxxxxx> to: user.xxxxxxxx at: 1411974127 uid: 24023 id: <E4Aa6n7XGPzsf%2FKcSmgv9w%3D%3D@xxxxxxxxxxxxxxx> to: user.xxxxxxxx at: 1411977693 uid: 24026 id: <E4Aa6n7XGPzsf%2FKcSmgv9w%3D%3D@xxxxxxxxxxxxxxx> to: user.xxxxxxxx at: 1411988514 uid: 24031 id: <E4Aa6n7XGPzsf%2FKcSmgv9w%3D%3D@xxxxxxxxxxxxxxx> to: user.xxxxxxxx at: 1411992092 uid: 24033 id: <E4Aa6n7XGPzsf%2FKcSmgv9w%3D%3D@xxxxxxxxxxxxxxx> to: user.xxxxxxxx at: 1412059168 uid: 24042 id: <E4Aa6n7XGPzsf%2FKcSmgv9w%3D%3D@xxxxxxxxxxxxxxx> to: user.xxxxxxxx at: 1412060492 uid: 24043 id: <E4Aa6n7XGPzsf%2FKcSmgv9w%3D%3D@xxxxxxxxxxxxxxx> to: user.xxxxxxxx at: 1412070549 uid: 24051 id: <E4Aa6n7XGPzsf%2FKcSmgv9w%3D%3D@xxxxxxxxxxxxxxx> to: user.xxxxxxxx at: 1412073074 uid: 24053 id: <E4Aa6n7XGPzsf%2FKcSmgv9w%3D%3D@xxxxxxxxxxxxxxx> to: user.xxxxxxxx at: 1412075354 uid: 24055 these are quite isolated incidents, but surely this shouldn't happen at all? I suppose I'm asking if there are any known reasons why the deduplication process might behave in this way? We run cyr_expire -E 1 every night Gavin Gray Edinburgh University Information Services Rm 2013 JCMB Kings Buildings Edinburgh EH9 3JZ UK tel +44 (0)131 650 5987 email gavin.gray@xxxxxxxx -- The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. ---- Cyrus Home Page: http://www.cyrusimap.org/ List Archives/Info: http://lists.andrew.cmu.edu/pipermail/info-cyrus/ To Unsubscribe: https://lists.andrew.cmu.edu/mailman/listinfo/info-cyrus