After some tests, we found that "dsync backup" sometimes fails to copy all the IMAP "keywords" (labels) from the source mailbox to the backup one. Our Dovecot version is 2.2.13 (Debian Jessie package 1:2.2.13-12~deb8u1). We are migrating mailboxes from MBOX (with separate indexes) to MDBOX (with custom DIRNAME) format. The source mail_location is: mail_location = mbox:~/mail:INBOX=~/mail/INBOX:INDEX=/var/cache/dovecot/indexes/%16Hu/%u and the target: mail_location = mdbox:~/mdbox:DIRNAME=_@@_dbox-Mails_@@_ and we use the following dsync command to replicate (twice, a first "hot" run, and a second "cold" run with lda and user kicked off). dsync -o mail_access_groups=$mgroup -u "$login" backup "mdbox:$mdbhome/mdbox:DIRNAME=_@@_dbox-Mails_@@_" where $login is username, $mgroup is an UNIX group which has write access to the (temporary chowned/chmoded) mailbox, and $mdbhome is the new (MDBOX) user's home. It appears that some keywords get replicated, but some other do not. The only workaroud we found is to backup all keywords with "doveadm fetch 'mailbox uid flags' keywords '*'", an restore them on the new mailbox with "doveadm flags add". This solution yields no keyword loss. has this problem already been addressed ? -- Benoit BRANCIARD Service InfraStructures (SIS) Direction du Syst?me d'Information et des Usages Num?riques (DSIUN) Universit? Paris 1 Panth?on-Sorbonne Centre Pierre Mend?s France 90 rue de Tolbiac - 75634 Paris cedex 13 - France Bur. B406 - T?l +33 1 44 07 89 68 - Fax +33 1 44 07 89 66 Accueil: +33 1 44 07 89 65 - Assistance-DSIUN at univ-paris1.fr http://dsi.univ-paris1.fr