We're in the process of migrating our dovecot 1.x mail server to a
Dovecot 2.2.25 server. During the migration I'm moving from mbox storage
I use the following method to do a one-way sync from our current mail
server to our new mail server (command executed on the new server):
doveadm -v -o imapc_host=oldserver \
-o imapc_user=$u \
-o imapc_master_user=$masteruser \
-o imapc_password="$masterpass" \
-o imapc_port=993 -o imapc_ssl=imaps \
-o ssl_client_ca_file=/etc/pki/tls/certs/ca-bundle.crt \
-o imapc_ssl_verify=yes \
-o mail_fsync=never \
-o mail_prefetch_count=20 \
backup -R -u $u imapc:
$u is replaced by the username I'm migrating.
The dsync command runs and exits with code 0 (all OK).
However, when I look at the subscriptions file on the new server, there
seem to be additional subscriptions that are not in the subscriptions
file on the old server:
Where do these come from? Is something wrong with the migration?
It also seems that subscriptions for IMAP folders that only contain
subfolders are no longer present in the new subscriptions file:
# diff -u sub-old.sorted sub-new.sorted
--- sub-old.sorted 2016-10-11 13:42:44.175070610 +0200
+++ sub-new.sorted 2016-10-11 13:47:53.973888462 +0200
@@ -1,26 +1,26 @@
Archive/Research/FET/VPH - Virtual Physiological Human
Archive/Research/Grants/ICON IBBT Call 2011
Archive/Research/Grants/Marie Curie ITN 2011
Is this expected behaviour?
 On the old server a folder can only contain either messages or
subfolders, not both at the same time.
KU Leuven - Dept. Elektrotechniek (ESAT)
Kasteelpark Arenberg 10 bus 2440 - B-3001 Leuven-Heverlee
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