I am migrating an old dovecot 2.2.30 (macOS High SIerra, macO S Server) to a new server with dovecot 2.3.7 (macOS Mojave, macports).

To get the data over, I’m trying to do a reverse backup with doveadm between an old and a new mail server, but failing to do so. I’m trying (from the new server, the old server is 192.168.2.67):

doveadm -Dv \
  -o imapc_host=192.168.2.67 \
  -o imapc_user=gerben \
  -o imapc_password=’[snip]' \
  -o imapc_features='rfc822.size fetch-headers’ \
  -o mail_prefetch_count=20 \
  -o mail_fsync=never \
  -o imapc_ssl=starttls \
  -o imapc_ssl_verify=no \
   backup -R -u gerben imapc:

It seems to start to work:

dsync(gerben): Debug: imapc(192.168.2.67:143): Created new connection
dsync(gerben): Debug: imapc(192.168.2.67:143): Looking up IP address (reconnect_ok=true, last_connect=1577059834)
dsync(gerben): Debug: imapc(192.168.2.67:143): Connecting to 192.168.2.67:143
dsync(gerben): Info: imapc(192.168.2.67:143): Connected to 192.168.2.67:143 (local 192.168.2.66:50804)
dsync(gerben): Debug: imapc(192.168.2.67:143): Server capabilities: IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE STARTTLS LOGINDISABLED XAPPLEPUSHSERVICE
dsync(gerben): Debug: imapc(192.168.2.67:143): Starting SSL handshake
dsync(gerben): Debug: imapc(192.168.2.67:143): SSL handshake successful, ignoring invalid certificate: SSL certificate doesn't match expected host name 192.168.2.67: No match to 2 SubjectAltNames
dsync(gerben): Debug: imapc(192.168.2.67:143): Server capabilities: IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE XAPPLEPUSHSERVICE AUTH=CRAM-MD5 AUTH=PLAIN AUTH=LOGIN AUTH=DIGEST-MD5 AUTH=GSSAPI
dsync(gerben): Debug: imapc(192.168.2.67:143): Authenticating as gerben
dsync(gerben): Debug: imapc(192.168.2.67:143): Server capabilities: IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE SORT SORT=DISPLAY THREAD=REFERENCES THREAD=REFS THREAD=ORDEREDSUBJECT MULTIAPPEND URL-PARTIAL CATENATE UNSELECT CHILDREN NAMESPACE UIDPLUS LIST-EXTENDED I18NLEVEL=1 CONDSTORE QRESYNC ESEARCH ESORT SEARCHRES WITHIN CONTEXT=SEARCH LIST-STATUS BINARY MOVE XAPPLEPUSHSERVICE COMPRESS=DEFLATE QUOTA ACL RIGHTS=texk
dsync(gerben): Debug: imapc(192.168.2.67:143): Authenticated successfully
dsync(gerben): Debug: imapc: root=, index=, indexpvt=, control=, inbox=, alt=
dsync(gerben): Debug: fts: Indexes disabled for namespace ''
dsync(gerben): Debug: brain S: Namespace  has location imapc:
dsync(gerben): Debug: brain M: Local mailbox tree: INBOX guid=184a4c066b219a5dd73700009e3b11ac uid_validity=1570382187 uid_next=18 subs=no last_change=0 last_subs=0
dsync(gerben): Debug: brain S: Local mailbox tree: INBOX guid=c92f64f79f0d1ed01e6d5b314f04886c uid_validity=1232523592 uid_next=482711 subs=no last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Local mailbox tree: Notspam_train guid=e0cc8c076b219a5dd73700009e3b11ac uid_validity=1570382188 uid_next=10 subs=no last_change=0 last_subs=0
dsync(gerben): Debug: brain S: Local mailbox tree: zzz-Old guid=c71fb29dcfd52e98ffb476033482311a uid_validity=1246525241 uid_next=1 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Local mailbox tree: Sent guid=e8c3b0076b219a5dd73700009e3b11ac uid_validity=1570382189 uid_next=17 subs=yes last_change=0 last_subs=1570382187
dsync(gerben): Debug: brain S: Local mailbox tree: zzz-Old/Werk guid=493c1b0ff8829799ae854dcdd35bdc49 uid_validity=1246525654 uid_next=1 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Local mailbox tree: Spam_train guid=7076d5076b219a5dd73700009e3b11ac uid_validity=1570382190 uid_next=3719 subs=no last_change=0 last_subs=0
dsync(gerben): Debug: brain S: Local mailbox tree: zzz-Old/Werk/UitNFIMailboxen guid=1da8c05ea358b80ee1c2f3a01cc7f2cc uid_validity=1232523595 uid_next=118 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Local mailbox tree: Trash guid=4810f5076b219a5dd73700009e3b11ac uid_validity=1570382191 uid_next=3 subs=no last_change=0 last_subs=0
dsync(gerben): Debug: brain S: Local mailbox tree: zzz-Old/Werk/RvdR guid=44c6bc132d8b2818930a6bcf0d2a5706 uid_validity=1232523595 uid_next=349 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Local mailbox tree: Junk guid=f8a063086b219a5dd73700009e3b11ac uid_validity=1570382194 uid_next=1 subs=no last_change=0 last_subs=0
dsync(gerben): Debug: brain S: Local mailbox tree: zzz-Old/Werk/Nieuwe Baan guid=75a5c26e35145b08ff594eb249867d0e uid_validity=1232523595 uid_next=380 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Local mailbox tree: Subfolder guid=d8d293340d2c9a5d1d3a00009e3b11ac uid_validity=1570382195 uid_next=1 subs=yes last_change=0 last_subs=1570384909
dsync(gerben): Debug: brain S: Local mailbox tree: zzz-Old/Werk/NFI guid=3d3c4682642c7ccb58523e0726a0ecff uid_validity=1232523595 uid_next=289 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Local mailbox tree: Subfolder/SUbSubFolder guid=08fb2d1a402c9a5d1d3a00009e3b11ac uid_validity=1570382196 uid_next=1 subs=yes last_change=0 last_subs=1570384960
dsync(gerben): Debug: brain S: Local mailbox tree: zzz-Old/Projects guid=7843f3ba3f3bfb3c4c965c1bd59b219a uid_validity=1246525385 uid_next=1 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Local mailbox tree: Archive guid=d89d4d148903005e6b5501009e3b11ac uid_validity=1570382197 uid_next=1 subs=yes last_change=0 last_subs=1570382187
dsync(gerben): Debug: brain S: Local mailbox tree: zzz-Old/Projects/TeX guid=2063d233e1533d17e6910c2d1c3d802c uid_validity=1232523594 uid_next=1 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Local mailbox tree: Drafts guid=60cd72148903005e6b5501009e3b11ac uid_validity=1570382198 uid_next=1 subs=yes last_change=0 last_subs=1570382187
dsync(gerben): Debug: brain S: Local mailbox tree: zzz-Old/Projects/TeX/Word Hell guid=bbd58ddde1f98e962507f8868f2b8372 uid_validity=1232523594 uid_next=123 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain S: Local mailbox tree: zzz-Old/Projects/TeX/TUG2003 guid=af8b9bd0abed0f24ff41acd3e0f6cfcf uid_validity=1232523594 uid_next=202 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain S: Local mailbox tree: zzz-Old/Projects/TeX/TUG ADC guid=2c828ce4f978e96b8199cd3364cf831a uid_validity=1232523594 uid_next=127 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Remote mailbox tree: INBOX guid=c92f64f79f0d1ed01e6d5b314f04886c uid_validity=1232523592 uid_next=482711 subs=no last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Remote mailbox tree: zzz-Old guid=c71fb29dcfd52e98ffb476033482311a uid_validity=1246525241 uid_next=1 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Remote mailbox tree: zzz-Old/Werk guid=493c1b0ff8829799ae854dcdd35bdc49 uid_validity=1246525654 uid_next=1 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Remote mailbox tree: zzz-Old/Werk/UitNFIMailboxen guid=1da8c05ea358b80ee1c2f3a01cc7f2cc uid_validity=1232523595 uid_next=118 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Remote mailbox tree: zzz-Old/Werk/RvdR guid=44c6bc132d8b2818930a6bcf0d2a5706 uid_validity=1232523595 uid_next=349 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Remote mailbox tree: zzz-Old/Werk/Nieuwe Baan guid=75a5c26e35145b08ff594eb249867d0e uid_validity=1232523595 uid_next=380 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Remote mailbox tree: zzz-Old/Werk/NFI guid=3d3c4682642c7ccb58523e0726a0ecff uid_validity=1232523595 uid_next=289 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Remote mailbox tree: zzz-Old/Projects guid=7843f3ba3f3bfb3c4c965c1bd59b219a uid_validity=1246525385 uid_next=1 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Remote mailbox tree: zzz-Old/Projects/TeX guid=2063d233e1533d17e6910c2d1c3d802c uid_validity=1232523594 uid_next=1 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Remote mailbox tree: zzz-Old/Projects/TeX/Word Hell guid=bbd58ddde1f98e962507f8868f2b8372 uid_validity=1232523594 uid_next=123 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Remote mailbox tree: zzz-Old/Projects/TeX/TUG2003 guid=af8b9bd0abed0f24ff41acd3e0f6cfcf uid_validity=1232523594 uid_next=202 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Remote mailbox tree: zzz-Old/Projects/TeX/TUG ADC guid=2c828ce4f978e96b8199cd3364cf831a uid_validity=1232523594 uid_next=127 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain S: Local mailbox tree: zzz-Old/Projects/TeX/TUG guid=0ff5d314b54457b60c266634bca9898a uid_validity=1232523594 uid_next=242 subs=yes last_change=0 last_subs=0
dsync(gerben): Debug: brain M: Remote mailbox tree: zzz-Old/Projects/TeX/TUG guid=0ff5d314b54457b60c266634bca9898a uid_validity=1232523594 uid_next=242 subs=yes last_change=0 last_subs=0

etc. Then, at some point, it changes to:

dsync(gerben): Debug: brain M: Mailbox AAA Superjunk: local=00000000000000000000000000000000/0/0, remote=3232b6d3762f0d825fa9c7a1499b292f/0/1: mailbox not selectable yet
dsync(gerben): Debug: brain M: Mailbox APG: local=00000000000000000000000000000000/0/0, remote=d857f802643888ecbec4214ad6b7717e/0/1: mailbox not selectable yet
dsync(gerben): Debug: brain M: Mailbox Administrator: local=00000000000000000000000000000000/0/0, remote=8be9e36e5e0d2a6a87de584aaca0193f/0/1: mailbox not selectable yet
dsync(gerben): Debug: brain M: Mailbox Apple: local=00000000000000000000000000000000/0/0, remote=e85a0aa21c23f5abd2975a89b6820d63/0/1: mailbox not selectable yet
dsync(gerben): Debug: brain M: Mailbox Apple Mail To Do: local=00000000000000000000000000000000/0/0, remote=6275568b3221fc326872b07eefccd0b2/0/1: mailbox not selectable yet
dsync(gerben): Debug: brain M: Mailbox Archive: local=d89d4d148903005e6b5501009e3b11ac/0/1, remote=51a58e1d1d5c491aac71488647b20224/0/1: GUIDs conflict - will be merged later
dsync(gerben): Debug: brain M: Mailbox Bounces: local=00000000000000000000000000000000/0/0, remote=3479a3b099333fa68dd4b912625af777/0/1: mailbox not selectable yet
dsync(gerben): Debug: brain M: Mailbox Calendar Events: local=00000000000000000000000000000000/0/0, remote=498953ab9976b9c77b62da8cb4dd790a/0/1: mailbox not selectable yet
dsync(gerben): Debug: brain M: Mailbox DMARC: local=00000000000000000000000000000000/0/0, remote=decbde7a60591d2b65d074f75f07845f/0/1: mailbox not selectable yet

with lots of 'mailbox not selectable yet'

After I see all the remote (old server) mailboxes being mentioned such, then I see

dsync(gerben): Debug: brain M: Deleting mailbox 'Archive' (GUID d89d4d148903005e6b5501009e3b11ac): UIDVALIDITY changed (1295434254 -> 1570382197)
dsync(gerben): Debug: brain M: Deleting mailbox 'Drafts' (GUID 60cd72148903005e6b5501009e3b11ac): UIDVALIDITY changed (1232523592 -> 1570382198)
dsync(gerben): Debug: brain M: Deleting mailbox 'INBOX' (GUID 184a4c066b219a5dd73700009e3b11ac): UIDVALIDITY changed (1232523592 -> 1570382187)
dsync(gerben): Debug: brain M: Deleting mailbox 'Junk' (GUID f8a063086b219a5dd73700009e3b11ac): UIDVALIDITY changed (1295433962 -> 1570382194)
dsync(gerben): Debug: brain M: Deleting mailbox 'Notspam_train' (GUID e0cc8c076b219a5dd73700009e3b11ac): Mailbox doesn't exist
dsync(gerben): Debug: brain M: Deleting mailbox 'Sent' (GUID e8c3b0076b219a5dd73700009e3b11ac): Mailbox doesn't exist
dsync(gerben): Debug: brain M: Deleting mailbox 'Spam_train' (GUID 7076d5076b219a5dd73700009e3b11ac): Mailbox doesn't exist
dsync(gerben): Debug: brain M: Deleting mailbox 'Subfolder/SUbSubFolder' (GUID 08fb2d1a402c9a5d1d3a00009e3b11ac): Mailbox doesn't exist
dsync(gerben): Debug: brain M: Deleting mailbox 'Subfolder' (GUID d8d293340d2c9a5d1d3a00009e3b11ac): Mailbox doesn't exist
dsync(gerben): Debug: brain M: Deleting mailbox 'Trash' (GUID 4810f5076b219a5dd73700009e3b11ac): Mailbox doesn't exist
dsync(gerben): Debug: doveadm-sieve: Iterating Sieve mailbox attributes
dsync(gerben): Debug: sieve: Pigeonhole version 0.5.7.1 () initializing
dsync(gerben): Debug: sieve: include: sieve_global is not set; it is currently not possible to include `:global' scripts.
dsync(gerben): Debug: sieve: Sieve imapsieve plugin for Pigeonhole version 0.5.7.1 () loaded
dsync(gerben): Debug: sieve: Sieve Extprograms plugin for Pigeonhole version 0.5.7.1 () loaded
dsync(gerben): Debug: sieve: file storage: Using active Sieve script path: /private/var/mail/nl.rna.mail/rules/gerben/dovecot.sieve
dsync(gerben): Debug: sieve: file storage: Using script storage path: /private/var/mail/nl.rna.mail/rules/gerben/gerben
dsync(gerben): Debug: sieve: file storage: Using permissions from /private/var/mail/nl.rna.mail/rules/gerben/gerben: mode=0700 gid=-1
dsync(gerben): Debug: sieve: file storage: Relative path to sieve storage in active link: gerben/
dsync(gerben): Debug: sieve: file storage: sync: Synchronization active
dsync(gerben): Debug: sieve: file storage: quota: Storage limit: 52428800 bytes
dsync(gerben): Error: Mailbox INBOX sync: mailbox_delete failed: INBOX can't be deleted.
dsync(gerben): Debug: brain S: Remote mailbox tree: INBOX guid=184a4c066b219a5dd73700009e3b11ac uid_validity=1570382187 uid_next=18 subs=no last_change=0 last_subs=0
dsync(gerben): Debug: brain S: Remote mailbox tree: Notspam_train guid=e0cc8c076b219a5dd73700009e3b11ac uid_validity=1570382188 uid_next=10 subs=no last_change=0 last_subs=0
dsync(gerben): Debug: brain S: Remote mailbox tree: Sent guid=e8c3b0076b219a5dd73700009e3b11ac uid_validity=1570382189 uid_next=17 subs=yes last_change=0 last_subs=1570382187
dsync(gerben): Debug: brain S: Remote mailbox tree: Spam_train guid=7076d5076b219a5dd73700009e3b11ac uid_validity=1570382190 uid_next=3719 subs=no last_change=0 last_subs=0
dsync(gerben): Debug: brain S: Remote mailbox tree: Trash guid=4810f5076b219a5dd73700009e3b11ac uid_validity=1570382191 uid_next=3 subs=no last_change=0 last_subs=0
dsync(gerben): Debug: brain S: Remote mailbox tree: Junk guid=f8a063086b219a5dd73700009e3b11ac uid_validity=1570382194 uid_next=1 subs=no last_change=0 last_subs=0
dsync(gerben): Debug: brain S: Remote mailbox tree: Subfolder guid=d8d293340d2c9a5d1d3a00009e3b11ac uid_validity=1570382195 uid_next=1 subs=yes last_change=0 last_subs=1570384909
dsync(gerben): Debug: brain S: Remote mailbox tree: Subfolder/SUbSubFolder guid=08fb2d1a402c9a5d1d3a00009e3b11ac uid_validity=1570382196 uid_next=1 subs=yes last_change=0 last_subs=1570384960
dsync(gerben): Debug: brain S: Remote mailbox tree: Archive guid=d89d4d148903005e6b5501009e3b11ac uid_validity=1570382197 uid_next=1 subs=yes last_change=0 last_subs=1570382187
dsync(gerben): Debug: brain S: Remote mailbox tree: Drafts guid=60cd72148903005e6b5501009e3b11ac uid_validity=1570382198 uid_next=1 subs=yes last_change=0 last_subs=1570382187
dsync(gerben): Debug: imapc(192.168.2.67:143): Disconnected

But nothing has been copied over and while it states it has deleted local mailboxes (such as Subfolder/SUbSubFolder), they are still there. In other words: nothing happens.

Well, not quite. The first time I ran this, local directory /var/mail/nl.rna.mail/rules/gerben/gerben/tmp was created.

Can anyone see here what is going wrong?

Gerben Wierda
Chess and the Art of Enterprise Architecture
Mastering ArchiMate
Architecture for Real Enterprises at InfoWorld
On Slippery Ice at EAPJ