Hello,

We are using dovecot with mdbox and ALT store on S3(Simple Storage System). We export the mail_location=mdbox:/<user-mailstore>/mdbox:ALT=/altmailstore/<user-mailstore>/mdbox of user in extra parameters. Today, alternate mail store of few users is disparaged unexpectedly which resulted in mail loss. We are unable to trace out why and when the alternate store is disparaged. Our hypothesis is, the folder is removed during doveadm altmove. We want to prevent this in future. It will be great if someone helps to identify the root cause.

Dovecot version: 2.2.19

# dovecot -n # 2.2.19: /etc/dovecot/dovecot.conf # OS: Linux 2.6.32-573.el6.x86_64 x86_64 CentOS Linux release 6.0 (Final) auth_mechanisms = plain login auth_verbose_passwords = plain disable_plaintext_auth = no mail_fsync = always mail_gid = 65111 mail_location = maildir:~/Maildir mail_nfs_index = yes mail_nfs_storage = yes mail_plugins = " quota" mail_uid = 65111 mdbox_rotate_interval = 1 days mdbox_rotate_size = 20 M mmap_disable = yes namespace inbox { inbox = yes location = mailbox Drafts { auto = create special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Sent { special_use = \Sent } mailbox "Sent Items" { auto = create } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { auto = create special_use = \Trash } mailbox chat { auto = create } prefix = INBOX. separator = . type = private } plugin { mail_log_events = delete undelete expunge copy mailbox_delete mailbox_rename mail_log_fields = uid box msgid size } ssl_cert = </conf/server/server.crt ssl_key = </conf/server/server.key

-- Sincerely, Prakash P. Autade.