- dovecot - dovecot.org

Re: Errors with missing links to files when using Single Instance Storage and zlib (Dovecot 2.3.4)
by Daniel Schütze 27 Dec '18

27 Dec '18

Having had a week with the system I'm now inclined to believe that the issues I've seen are not necessarily related to SIS and zlib but may be due to replication instead. After experiencing these issues and looking at historical mailing list posts I wrote a basic script (as was suggested as a possible diagnostic approach for SIS before SIS was even implemented!) which pulled all the mail from a user doveadm fetch -u username body all > /dev/null 2>error.log This generated errors in error.log for every e-mail with a problem. From that and some use of sed,uniq,cut and ln I was able to (re)create the missing links. Unfortunately the error generated was only the first missing link for all the links expected for an e-mail. So my script had to be run multiple times per user until no more errors were reported. This wasn't all that onerous given I was basically running on a test box before mass migrating my users. A better approach would have been to scan the mdbox files for all links expected and check the existence of them all. Having (re)created all missing links I've not had a single instance of a link being missing after a week of delivery of mail (where the errors were regular before this procedure). I have also since looked at how replication handles links. What I hadn't expected was that the links created on the server pair are not the same. Although I had two servers which started in the same state (one a clone of the other) after a month or so of replication they had diverged to the state where if I sent a test message to the one server I could see the file name of the link created to the has was not the same on both servers (although obviously the hash itself was the same name and content wise). This leads me to believe the errors I saw where most likely down to my expecting the two servers in the pair to have identical SIS attachment directories/hardlinks to hashes and the way I handled my migration. Coming from a database mail server were replication master/slave means the backend should be absolutely identical if all is working I may simply have gotten the wrong idea of dovecot replication. With my 2.3.1 and 2.3.4 replication pair there were a lot of the tcp errors which the changelog for Dovecot stated had been fixed post 2.3.1; mainly the connection timing out after 10 minutes. Looking at the code for replication (which I'm not going to claim I've fully go to grips with) it looks like the name of a hardlink is made up of essentially [hash]-[identifier including mailbox GUID]. It must be the case then that the [identifier including mailbox GUID] can diverge between server pairs, at least with 2.3.1 as a version involved. Errors with missing links to files when using Single Instance Storage and zlib (Dovecot 2.3.4) *Daniel Schütze*daniel at cwa.uk.com<mailto:dovecot%40dovecot.org?Subject=Re:%20Re%3A%20Errors%20with%20missing%20links%20to%20files%20when%20using%20Single%20Instance%20Storage%0A%20and%20zlib%20%28Dovecot%202.3.4%29&In-Reply-To=%3Ccc3b8bf3-055f-6908-95a0-d337544a8998%40cwa.uk.com%3E> /Tue Dec 18 15:39:41 EET 2018/ * Previous message:Change default mode for attachment files <https://www.dovecot.org/pipermail/dovecot/2018-December/113952.html> * Next message:High Load average on NFS Spool - v.2.1.15 & 2.2.13 <https://www.dovecot.org/pipermail/dovecot/2018-December/113957.html> * *Messages sorted by:*[ date ] <https://www.dovecot.org/pipermail/dovecot/2018-December/date.html#113954>[ thread ] <https://www.dovecot.org/pipermail/dovecot/2018-December/thread.html#113954>[ subject ] <https://www.dovecot.org/pipermail/dovecot/2018-December/subject.html#113954>[ author ] <https://www.dovecot.org/pipermail/dovecot/2018-December/author.html#113954> ------------------------------------------------------------------------ I'm running Dovecot 2.3.4 with Single Instance Storage (SIS) and zlib and I am frequently seeing errors where files are missing in the attachments directory even though the zipped file in the hash directory is actually there. This appears not to have been an issue in Dovecot 2.3.1 Requested output of the server below. The error looks like this in the log Dec 18 08:58:58 dovecot01 dovecot: imap(username)<3692><RKnPGEh9fC3AqAAB>: Error: Mailbox INBOX/FOLDER: UID=41: read(attachments-connector(zlib(/usr/home/vmail/mail/username//mdbox/storage/m.411))) failed: read(/usr/home/vmail/attachments/91/08/91085773a0774909207852b8f9c98dbe22fe5a31-e88ba0276aae135cd2050000d09efc50[base64:19 b/l]) failed: open(/usr/home/vmail/attachments/91/08/91085773a0774909207852b8f9c98dbe22fe5a31-e88ba0276aae135cd2050000d09efc50) failed: No such file or directory (FETCH BODY[]) I'm also seeing errors when replication fails dovecot: dsync-local(username)<bzg3MqjhGFxmFwAAzRvpBw>: Error: dsync(servername): read(attachments-connector(zlib(/usr/home/vmail/mail/username//mdbox/storage/m.413))) failed: read(/usr/home/vmail/attachments/45/42/4542dcf385f6b4a4dc8752b96db1d7ad8a8023d5-ac735007f6bd135c93440100cd1be907[base64:19 b/l]) failed: open(/usr/home/vmail/attachments/45/42/4542dcf385f6b4a4dc8752b96db1d7ad8a8023d5-ac735007f6bd135c93440100cd1be907) failed: No such file or directory (last sent=mail, last recv=mail (EOL)) It is not the case that every replication fail has a corresponding imap access fail. I am running Dovecot 2.3.4 on FreeBSD11.2 and I did not see this error on Dovecot 2.3.1 FreeBSD 10.4. Both installs had the same configuration for Dovecot. Both installs were made from source code and not packages (as the need for the non standard fts and mysql options). During my testing I had the 2.3.1 install receive mail and replicate to the 2.3.4 and that was working fine (except for tcp connection issues which I saw was fixed in the changelog). Unfortunately having gone into testing with real account and mail being sent to the 2.3.4 install I'm seeing the above errors. My clients are using Thunderbird on desktops and Roundcube for webmail. My users report they can see the e-mails fine in their webmail (Roundcube) and only Thunderbird is giving issues. I admit I don't know how this can be the case as both systems use the same account details. In everycase so far there is a file in the hashes directory I have hand crafted the missing file (i.e. link) using ln and this restores access in Thunderbird. Clearly this is an big issue for my install and I'd appreciate any help! At the moment it looks like my course will be to try and script creation (recreation?) of the links from the error logs (I've seen people talking about this online) but that isn't really what I'm after. DOVECOT CONFIG # 2.3.4 (0ecbaf23d): /usr/local/etc/dovecot/dovecot.conf # Pigeonhole version 0.5.4 (60b0f48d) # OS: FreeBSD 11.2-RELEASE-p5 amd64 # Hostname: dovecot01.cwa.uk.com dict { acl = mysql:/usr/local/etc/dovecot/dovecot-dict-sql.conf.ext } disable_plaintext_auth = no doveadm_password = # hidden, use -P to show it first_valid_uid = 145 last_valid_uid = 145 mail_access_groups = mail mail_attachment_dir = /usr/home/vmail/attachments mail_attachment_min_size = 64 k mail_gid = vmail mail_location = mdbox:~/mdbox:INDEX=/indexdisk/indexes/%n mail_plugins = " fts fts_solr acl zlib notify replication" mail_privileged_group = mail mail_uid = vmail managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext namespace { list = yes location = mdbox:%%h/mdbox:INDEXPVT=~/mdbox/shared/%%n prefix = shared/%%n/ separator = / subscriptions = yes type = shared } namespace inbox { inbox = yes location = mailbox Drafts { auto = subscribe special_use = \Drafts } mailbox Junk { auto = subscribe special_use = \Junk } mailbox Sent { auto = subscribe special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { auto = subscribe special_use = \Trash } prefix = type = private } passdb { args = /usr/local/etc/dovecot/dovecot-sql.conf.ext driver = sql } plugin { acl = vfile acl_shared_dict = proxy::acl fts = solr fts_autoindex = yes fts_solr = url=http://localhost:8983/solr/dovecot/ mail_replica = tcp:192.168.0.138:12345 replication_dsync_parameters = -d -l 30 -U sieve = ~/.dovecot.sieve sieve_dir = ~/sieve sieve_duplicate_default_period = 1h sieve_duplicate_max_period = 1d sieve_global_dir = /usr/home/vmail/sieve/global/ sieve_global_path = /usr/home/vmail/default.sieve sieve_vacation_default_period = 1d zlib_save = gz zlib_save_level = 6 } protocols = imap sieve service aggregator { fifo_listener replication-notify-fifo { user = vmail } unix_listener replication-notify { user = vmail } } service auth { unix_listener auth-userdb { mode = 0777 } } service dict { unix_listener dict { mode = 0600 user = vmail } } service doveadm { inet_listener { port = 12345 } } service replicator { process_min_avail = 1 unix_listener replicator-doveadm { mode = 0600 user = vmail } } ssl = no userdb { driver = prefetch } userdb { args = /usr/local/etc/dovecot/dovecot-sql.conf.ext driver = sql } protocol lda { mail_plugins = " fts fts_solr acl zlib notify replication sieve" submission_host = 192.168.0.1:25 } protocol imap { mail_plugins = " fts fts_solr acl zlib notify replication imap_acl imap_zlib" } ------------------------------------------------------------------------ * Previous message:Change default mode for attachment files <https://www.dovecot.org/pipermail/dovecot/2018-December/113952.html> * Next message:High Load average on NFS Spool - v.2.1.15 & 2.2.13 <https://www.dovecot.org/pipermail/dovecot/2018-December/113957.html> * *Messages sorted by:*[ date ] <https://www.dovecot.org/pipermail/dovecot/2018-December/date.html#113954>[ thread ] <https://www.dovecot.org/pipermail/dovecot/2018-December/thread.html#113954>[ subject ] <https://www.dovecot.org/pipermail/dovecot/2018-December/subject.html#113954>[ author ] <https://www.dovecot.org/pipermail/dovecot/2018-December/author.html#113954> ------------------------------------------------------------------------ More information about the dovecot mailing list <https://dovecot.org/mailman/listinfo/dovecot>

1 0

Segfault report
by Daniel Miller 27 Dec '18

27 Dec '18

Ubuntu 18.04, AMD Opteron, Dovecot Version 2.3.3, local file storage. I believe it's one of my users checking mail remotely via mobile - don't remember if it's an iPhone or Android. gdb backtrace: Reading symbols from /usr/local/libexec/dovecot/imap...done. [New LWP 13852] [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". Core was generated by `dovecot/imap [kkhany(a)amfes.c'. Program terminated with signal SIGSEGV, Segmentation fault. #0 event_want_debug_log (event=event@entry=0x0, source_filename=source_filename@entry=0x7efd84178aa3 "mail-storage.c", source_linenum=source_linenum@entry=1261) at event-log.c:120 120 if (event->forced_debug) (gdb) bt full #0 event_want_debug_log (event=event@entry=0x0, source_filename=source_filename@entry=0x7efd84178aa3 "mail-storage.c", source_linenum=source_linenum@entry=1261) at event-log.c:120 ctx = {type = LOG_TYPE_DEBUG, exit_status = 0, timestamp = 0x0, timestamp_usecs = 0, log_prefix = 0x0, log_prefix_type_pos = 0} #1 0x00007efd83dc0986 in event_want_debug (event=event@entry=0x0, source_filename=source_filename@entry=0x7efd84178aa3 "mail-storage.c", source_linenum=source_linenum@entry=1261) at event-log.c:140 No locals. #2 0x00007efd840bf270 in mailbox_open_full (box=box@entry=0x55704dc81058, input=input@entry=0x0) at mail-storage.c:1259 _tmp_event = 0x0 ret = <optimized out> #3 0x00007efd840bf57a in mailbox_open_full (input=0x0, box=0x55704dc81058) at mail-storage.c:1368 ret = <optimized out> ret = <optimized out> _tmp_event = <optimized out> _data_stack_cur_id = <optimized out> _data_stack_cur_id = <optimized out> #4 mailbox_open (box=0x55704dc81058) at mail-storage.c:1349 No locals. #5 0x000055704c36a31b in select_open (readonly=false, mailbox=<optimized out>, ctx=0x55704dc13bc8) at cmd-select.c:288 client = 0x55704dc11de8 status = {messages = 1830951344, recent = 32766, unseen = 2391910144, uidvalidity = 1475818629, uidnext = 1830951424, first_unseen_seq = 32766, first_recent_uid = 1832402502, last_cached_seq = 32766, highest_modseq = 0, highest_pvt_modseq = 4294967296, keywords = 0x55704dbf1380, permanent_flags = 1280910144, flags = 21872, permanent_keywords = false, allow_new_keywords = false, nonpermanent_modseqs = false, no_modseq_tracking = false, have_guids = false, have_save_guids = true, have_only_guid128 = false} flags = <optimized out> ---Type <return> to continue, or q <return> to quit--- ret = 0 client = <optimized out> status = <optimized out> flags = <optimized out> ret = <optimized out> #6 cmd_select_full (cmd=<optimized out>, readonly=<optimized out>) at cmd-select.c:417 client = 0x55704dc11de8 ctx = <optimized out> args = 0x55704dbef690 list_args = 0x5d0000006e mailbox = 0x55704dbe1540 "shared" error = 0x55704dc11de8 "" ret = <optimized out> __func__ = "cmd_select_full" #7 0x000055704c371e30 in command_exec (cmd=cmd@entry=0x55704dc13a38) at imap-commands.c:201 hook = 0x55704dbeb0f0 finished = <optimized out> __func__ = "command_exec" #8 0x000055704c3701d2 in client_command_input (cmd=<optimized out>, cmd@entry=0x55704dc13a38) at imap-client.c:1152 client = 0x55704dc11de8 command = <optimized out> __func__ = "client_command_input" #9 0x000055704c370274 in client_command_input (cmd=<optimized out>) at imap-client.c:1215 client = 0x55704dc11de8 command = <optimized out> __func__ = "client_command_input" #10 0x000055704c370675 in client_handle_next_command (remove_io_r=<synthetic pointer>, client=0x55704dc11de8) at imap-client.c:1257 ---Type <return> to continue, or q <return> to quit--- No locals. #11 client_handle_input (client=0x55704dc11de8) at imap-client.c:1271 _data_stack_cur_id = 3 ret = <optimized out> remove_io = false ret = <optimized out> remove_io = <optimized out> client = 0x55704dc11de8 handled_commands = <optimized out> _data_stack_cur_id = <optimized out> ret = <optimized out> remove_io = <optimized out> _data_stack_cur_id = <optimized out> #12 0x000055704c370ccc in client_input (client=0x55704dc11de8) at imap-client.c:1317 cmd = 0x55704dc0bcb0 output = 0x55704dc2d150 bytes = 17 __func__ = "client_input" #13 0x00007efd83ddae0f in io_loop_call_io (io=0x55704dc13910) at ioloop.c:698 ioloop = 0x55704dbe9ee0 t_id = 2 __func__ = "io_loop_call_io" #14 0x00007efd83ddc7c6 in io_loop_handler_run_internal (ioloop=ioloop@entry=0x55704dbe9ee0) at ioloop-epoll.c:221 ctx = 0x55704dbedc00 events = <optimized out> event = <optimized out> list = 0x55704dc13970 ---Type <return> to continue, or q <return> to quit--- io = <optimized out> tv = {tv_sec = 1799, tv_usec = 999365} events_count = <optimized out> msecs = <optimized out> ret = <optimized out> i = 0 j = <optimized out> call = <optimized out> __func__ = "io_loop_handler_run_internal" #15 0x00007efd83ddaf1c in io_loop_handler_run (ioloop=<optimized out>) at ioloop.c:750 No locals. #16 0x00007efd83ddb138 in io_loop_run (ioloop=0x55704dbe9ee0) at ioloop.c:723 __func__ = "io_loop_run" #17 0x00007efd83d50873 in master_service_run (service=0x55704dbe9d70, callback=<optimized out>) at master-service.c:775 No locals. #18 0x000055704c362611 in main (argc=<optimized out>, argv=<optimized out>) at main.c:521 set_roots = {0x55704c5909a0 <smtp_submit_setting_parser_info>, 0x55704c5906c0 <imap_setting_parser_info>, 0x0} login_set = {auth_socket_path = 0x55704dbe12a8 "\340\022\276MpU", postlogin_socket_path = 0x55704dbe12f0 "m 174.237.3.103 SELECT]", postlogin_timeout_secs = 60, callback = 0x55704c37ed60 <login_client_connected>, failure_callback = 0x55704c37e530 <login_client_failed>, request_auth_token = true} service_flags = <optimized out> storage_service_flags = <optimized out> username = 0x0 auth_socket_path = <optimized out> c = <optimized out> error = 0x0 doveconf -n: # 2.3.3 (dcead646b): /usr/local/etc/dovecot/dovecot.conf # Pigeonhole version 0.5.3 (f018bbab) # OS: Linux 4.15.0-43-generic x86_64 Ubuntu 18.04.1 LTS # Hostname: bubba.amfes.lan auth_cache_size = 4 k auth_master_user_separator = * auth_mechanisms = plain login default_login_user = nobody default_vsz_limit = 1 G dict { acl = mysql:/usr/local/etc/dovecot/dovecot-dict-sql.conf.ext } disable_plaintext_auth = no imap_client_workarounds = tb-extra-mailbox-sep imap_idle_notify_interval = 29 mins listen = * mail_attachment_hash = %{sha512} mail_plugins = fts fts_solr acl zlib virtual mail_prefetch_count = 10 mail_shared_explicit_inbox = yes managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext namespace inbox { hidden = no inbox = yes list = yes location = mailbox "Deleted Messages" { auto = no autoexpunge = 30 days special_use = \Trash } mailbox Drafts { auto = subscribe special_use = \Drafts } mailbox INBOX/Archives { auto = no special_use = \Archive } mailbox Sent { auto = subscribe special_use = \Sent } mailbox "Sent Items" { auto = no special_use = \Sent } mailbox "Sent Messages" { auto = no special_use = \Sent } mailbox Trash { auto = subscribe autoexpunge = 30 days special_use = \Trash } mailbox virtual/Flagged { comment = All my flagged messages special_use = \Flagged } prefix = separator = / subscriptions = yes type = private } namespace usershares { list = children location = sdbox:/var/mail/%%d/%%n/sdbox prefix = shared/%%n/ separator = / subscriptions = no type = shared } namespace virtual { list = children location = virtual:/var/mail/%d/%n/virtual prefix = virtual/ separator = / subscriptions = no } passdb { args = /usr/local/etc/dovecot/master-users driver = passwd-file master = yes } passdb { args = /usr/local/etc/dovecot/dovecot-ldap.conf.ext driver = ldap } plugin { acl = vfile:/usr/local/etc/dovecot/global-acls:cache_secs=300 acl_shared_dict = proxy::acl fts = solr fts_autoindex = yes fts_solr = break-imap-search url=http://127.0.0.1:8983/solr/dovecot/ mailbox_alias_new = Sent Messages mailbox_alias_new2 = Sent Items mailbox_alias_new3 = Deleted Messages mailbox_alias_old = Sent mailbox_alias_old2 = Sent mailbox_alias_old3 = Trash sieve = file:~/sieve;active=~/.dovecot.sieve } protocols = imap lmtp sieve service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0660 user = postfix } unix_listener auth-userdb { group = mail mode = 0600 user = vmail } } service dict { unix_listener dict { group = mail mode = 0660 user = vmail } } service imap-login { process_min_avail = 10 service_count = 1 } service imap-postlogin { executable = script-login /usr/local/etc/dovecot/post-login.sh user = $default_internal_user } service imap { executable = imap imap-postlogin } service lmtp { process_min_avail = 5 unix_listener /var/spool/postfix/private/dovecot-lmtp { group = mail mode = 0666 user = vmail } } service managesieve-login { inet_listener sieve { port = 4190 } inet_listener sieve_deprecated { port = 2000 } process_min_avail = 0 service_count = 1 } ssl_cert = </etc/letsencrypt/live/mail.amfes.com/fullchain.pem ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it userdb { driver = prefetch } userdb { args = /usr/local/etc/dovecot/dovecot-ldap.conf.ext driver = ldap } verbose_proctitle = yes protocol lmtp { mail_plugins = fts fts_solr acl zlib virtual sieve postmaster_address = postmaster(a)amfes.com } protocol lda { mail_plugins = fts fts_solr acl zlib virtual sieve } protocol imap { mail_max_userip_connections = 50 mail_plugins = fts fts_solr acl zlib virtual imap_acl imap_zlib mailbox_alias } local 192.168.0.2 { protocol imap { ssl_cert = </etc/letsencrypt/live/mail.amfes.com/fullchain.pem ssl_key = # hidden, use -P to show it } } -- Daniel

2 3

Migration to 2.3.36 using replication
by Thomas Durand 26 Dec '18

26 Dec '18

Hello, I have to migrate my dovecot box to a new one. I would like to know if it’s possible to do this migration with the replication process. My plan is to activate replication between 2.2.10 server and the 2.3.4 new server. Then I will update the DNS to redirect the name to new box. Users will then connect either on the new or the old box depending on the dns upgrade. Does anyone have already experienced such process ? Is there any incompatibility issue ? Thanks. Thomas

1 0

Heads-up regarding non-replication of Sieve scripts?
by Markus Ueberall 25 Dec '18

25 Dec '18

Dear all, A couple of months ago, it has been mentioned that multiple users experienced a problem regarding the synchronisation of Sieve scripts by means of "dsync" (whereas e-mails were replicated just fine between servers) [1][2] for Dovecot v2.3.x; the same problem apparently occurred with early versions from the v2.2 branch some three years ago but has been marked/confirmed as fixed back then [3]. Since I'm currently using the 2.2.33.2[-1ubuntu3] packages from the Dovecot community software repository and would like to upgrade to v2.3.x at one point, I'm very interested in hearing whether the above problems have been fixed (if so, how?) since I do not want to semi-manually synchronise the Sieve scripts between two mail servers in active/active mode on my own. Thanks in advance for a heads-up / Kind regards, Markus [1] https://www.dovecot.org/pipermail/dovecot/2018-October/113244.html [2] https://www.dovecot.org/pipermail/dovecot/2018-August/112548.html [3] https://www.dovecot.org/pipermail/dovecot/2015-February/099658.html

1 0

Authentication Problem
by Odhiambo Washington 21 Dec '18

21 Dec '18

I am using SHA512-CRYPT scheme for passwords. In my dovecot-sql.conf.ext, I have: default_pass_scheme = CRYPT In 10-auth.conf, I have: auth_mechanisms = plain login digest-md5 M$ Outlook is refusing to authenticate, with error: Requested DIGEST-MD5 scheme, but we have only CRYPT What an I missing?? I hate it that this has taken me round in circles :-) -- Best regards, Odhiambo WASHINGTON, Nairobi,KE +254 7 3200 0004/+254 7 2274 3223 "Oh, the cruft.", grep ^[^#] :-)

4 12

Password expiration: how to trigger it?
by Cédric Jeanneret 21 Dec '18

21 Dec '18

Dear Dovecot Team, I'm in the (long) process of migrating my whole email infrastructure. Of course, dovecot is in the place, and is working just fine. Still, I have an issue: password expiration. I'm now using FreeIPA backend for the user authentication, and it includes the capacity to expire passwords. Basically, it's an LDAP with fancy things, among them a field named krbPasswordExpiration (yes, that's kerberos). In order to make things simple, I'd rather NOT force my users to set up a kerberos/gssapi/whatever on their personal computer (most of them will just have blank gaze if I start talking about that). Is there a way to make Dovecot use that field? It's apparently a simple date in %Y%M%D%H%m%sZ format, so a pretty neat thing to test. If there's some support for that in Dovecot, that is. If not, as a last resort, I can configure the freeIPA to deactivate the user if the password is expired, and this should push another field in the user description. Would that be a possibility for Dovecot, in case it can't use the datetime field as is? Thank you for your support! Cheers, C.

2 1

outlook idiocy - IMAP folders with /
by Wojciech Puchar 20 Dec '18

20 Dec '18

user attempts to create folders with / dovecot naturally cannot create it so it returns error but outlook of course "create" it and keep data in local store only. data is lost when you remove local store .pst file. The question is - can dovecot be configured so it will automatically replace slash in name with something else?

8 15

SIS feature request
by Daniel Miller 20 Dec '18

20 Dec '18

I tried SIS a couple years ago - I was very excited with the resulting decrease in storage requirements but the undiagnosed intermittent issues became too significant to ignore so I switched away. Recently I was thinking about it again. The primary issue with SIS seemed to be links would be deleted even though the source attachment files and related mails still existed. It was possible to either manually re-build the links or have a script scan the mail error log and perform such. I haven't looked at the code - but a thought for a possible "temporary" fix: 1. Whatever function in dbox code that performs the deletion of links - prior to actually deleting call a new function that will verify if any mails exist that reference it. A new function, without modifying existing code, may catch something the existing functions don't - and if it logs the fact that it was called and found something...perhaps we can find the flaw in the original algorithm. Just a thought. 2. In the mail retrieval function, if the attachment link doesn't exist - perform the relevant scan through the attachment database and if found re-create the link automatically. This should log an error but indicate the recovery. -- Daniel

1 0

Intentionally use weak server key
by Stavros Tsolakos 20 Dec '18

20 Dec '18

Hi list! For some reason I need to use a really weak server key (256 bit) with dovecot for imaps access. Is this possible? I tried but getting this error: dovecot: imap-login: Error: SSL: Stacked error: error:04075070:rsa routines:RSA_sign:digest too big for rsa key This is on an Ubuntu 14.04 on x64. Thank you! Stavros

4 7

High Load average on NFS Spool - v.2.1.15 & 2.2.13
by Albert E. Whale, CEH CHS CISA CISSP 19 Dec '18

19 Dec '18

I have two servers pointing to an NFS mounted mail spool with dovecot. Since I recently switched from using Dovecot v1.X, I have been experiencing high CPU use with the two Dovecot servers. I am not certain why they are not well behaved. Here is the configuration information. This configuration is currently running at a load average of 17. /usr/sbin/dovecot -n # 2.1.15: /etc/dovecot/dovecot.conf # OS: Linux 3.10.54-server-2.mga3 i686 Mageia 3 base_dir = /var/run/dovecot/ disable_plaintext_auth = no lock_method = dotlock login_greeting = SpamZapper Email ready. login_log_format_elements = user=<%u> method=%m rip=%r lip=%l %c mail_debug = yes mail_fsync = always mail_location = maildir:~/Maildir mail_nfs_index = yes mail_nfs_storage = yes mail_privileged_group = mail mbox_lock_timeout = 15 mins mmap_disable = yes passdb { driver = pam } protocols = imap pop3 service anvil { client_limit = 203 process_limit = 1 } service auth { user = root } service imap-login { chroot = login client_limit = 10 user = dovecot vsz_limit = 256 M } service pop3-login { chroot = login client_limit = 20 user = dovecot } ssl = no syslog_facility = local2 userdb { driver = passwd } verbose_proctitle = yes protocol pop3 { mail_max_userip_connections = 20 pop3_logout_format = top=%t/%p, retr=%r/%b, del=%d/%m, size=%s pop3_uidl_format = %08Xv%08Xu } protocol lda { postmaster_address = postmaster(a)example.com } protocol imap { mail_max_userip_connections = 10 } And the other server which is currently running with a load average of 10. dovecot -n # 2.2.13: /etc/dovecot/dovecot.conf doveconf: Warning: service anvil { client_limit=100 } is lower than required under max. load (303) # OS: Linux 4.1.15-server-2.mga5 x86_64 Mageia 4 base_dir = /var/run/dovecot/ disable_plaintext_auth = no listen = * lock_method = dotlock login_greeting = SpamZapper Email ready. login_log_format_elements = user=<%u> method=%m rip=%r lip=%l %c mail_fsync = always mail_location = maildir:~/Maildir mail_nfs_index = yes mail_nfs_storage = yes mail_privileged_group = mail mmap_disable = yes passdb { driver = pam } protocols = imap pop3 service anvil { client_limit = 100 process_limit = 1 } service auth { user = root } service imap-login { chroot = login client_limit = 48 user = dovecot vsz_limit = 256 M } service pop3-login { chroot = login client_limit = 50 user = dovecot } ssl = no syslog_facility = local2 userdb { driver = passwd } verbose_proctitle = yes protocol pop3 { mail_max_userip_connections = 50 pop3_logout_format = top=%t/%p, retr=%r/%b, del=%d/%m, size=%s pop3_uidl_format = %08Xv%08Xu } protocol lda { postmaster_address = postmaster(a)example.com } protocol imap { mail_max_userip_connections = 40 } Can you please offer a suggestion on what is happening? The timeouts to the imap server are frequent due to the load average. Thank you. -- -- -- Albert E. Whale, CEH CHS CISA CISSP *President - Chief Info Security Officer* IT Security, Inc. <http://www.IT-Security-inc.com> - A Service Disabled Veteran Owned Company - (*SDVOSB*) *HUBZone Certified* LinkedIn <https://www.linkedin.com/in/albertwhale> Profile Phone: 412-515-3010 | Email: Albert.Whale(a)IT-Security-inc.com Cell: 412-889-6870

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Re: How to configure Dovecot to disable NIST's curves and still rertain EECDH?
by Kurt Fitzner 19 Dec '18

19 Dec '18

My opinion is that security by RFC is not security, it's mommy medicine. Standards have had a terrible time keeping up with security realities. NITS's curves leak side channel information all over the place. I don't have details on what implementations are set to calculate the NIST curves in constant time, and that's not an easy feat to do anyway so I don't want to depend on implementations that say they are actually doing it the right way. Frankly I can't be bothered to keep up with that. There are better curves TODAY, so yes I intend to use them if I can find a way. Otherwise, I'll just keep EECDH disabled. I have EDH now, and I've not yet run into a client that doesn't support it. I want EECDH, but I won't use it without safe curves. I'm confident that EECDH with safe curves and a second choice of EDH will support any clients that are worth using. OpenSSL supports X25519, and that is half the battle. Is there a way to change the curve selection in Dovecot? On 2018-12-19 01:49, Tributh via dovecot wrote: > Do you really plan to do this? > RFC 8446 section 9.1: > A TLS-compliant application MUST support key exchange with secp256r1 > (NIST P-256) and SHOULD support key exchange with X25519 > > I think your idea could be not future proved. > > Beside that, how many mail-clients will remain usable with this cipher > selection? > > Torsten

2 1

How to configure Dovecot to disable NIST's curves and still rertain EECDH?
by Kurt Fitzner 19 Dec '18

19 Dec '18

I am interested in configuring Dovecot's TLS so as to retain forward secrecy, but eliminate all of NIST's elliptic curves. Besides being subject to side channel attacks [1], in some quarters there is a general distrust of NIST's curves and any of their other cryptographic primitives after the Dual EC DRBG debacle. >From what I can tell, the following will prevent the use of NIST's curves (along with other dangerous primitives) in Dovecot, but this is accomplished by simply disabling EECDH entirely. ssl_cipher_list = HIGH:!DSS:!EECDH:!ECDH:!SHA1:!aNULL:!eNULL:@STRENGTH This should still retain forward secrecy through the use of EDH, but this doesn't leave much in the way of allowable algorithms on my server: $ openssl ciphers -V 'HIGH:!DSS:!EECDH:!ECDH:!SHA1:!aNULL:!eNULL:@STRENGTH' 0x00,0x9F - DHE-RSA-AES256-GCM-SHA384 TLSv1.2 Kx=DH Au=RSA Enc=AESGCM(256) Mac=AEAD 0x00,0x6B - DHE-RSA-AES256-SHA256 TLSv1.2 Kx=DH Au=RSA Enc=AES(256) Mac=SHA256 0x00,0x9D - AES256-GCM-SHA384 TLSv1.2 Kx=RSA Au=RSA Enc=AESGCM(256) Mac=AEAD 0x00,0x3D - AES256-SHA256 TLSv1.2 Kx=RSA Au=RSA Enc=AES(256) Mac=SHA256 0x00,0x9E - DHE-RSA-AES128-GCM-SHA256 TLSv1.2 Kx=DH Au=RSA Enc=AESGCM(128) Mac=AEAD 0x00,0x67 - DHE-RSA-AES128-SHA256 TLSv1.2 Kx=DH Au=RSA Enc=AES(128) Mac=SHA256 0x00,0x9C - AES128-GCM-SHA256 TLSv1.2 Kx=RSA Au=RSA Enc=AESGCM(128) Mac=AEAD 0x00,0x3C - AES128-SHA256 TLSv1.2 Kx=RSA Au=RSA Enc=AES(128) Mac=SHA256 Is there a better way to do this? Is there a way to disable only the suspect NIST curves and still retain EECDH but with side-channel safe curves like X25519? Thanks, Kurt Fitzner Links: ------ [1] https://blog.cr.yp.to/20140323-ecdsa.html

2 1

Errors with missing links to files when using Single Instance Storage and zlib (Dovecot 2.3.4)
by Daniel Schütze 18 Dec '18

18 Dec '18

I'm running Dovecot 2.3.4 with Single Instance Storage (SIS) and zlib and I am frequently seeing errors where files are missing in the attachments directory even though the zipped file in the hash directory is actually there. This appears not to have been an issue in Dovecot 2.3.1 Requested output of the server below. The error looks like this in the log Dec 18 08:58:58 dovecot01 dovecot: imap(username)<3692><RKnPGEh9fC3AqAAB>: Error: Mailbox INBOX/FOLDER: UID=41: read(attachments-connector(zlib(/usr/home/vmail/mail/username//mdbox/storage/m.411))) failed: read(/usr/home/vmail/attachments/91/08/91085773a0774909207852b8f9c98dbe22fe5a31-e88ba0276aae135cd2050000d09efc50[base64:19 b/l]) failed: open(/usr/home/vmail/attachments/91/08/91085773a0774909207852b8f9c98dbe22fe5a31-e88ba0276aae135cd2050000d09efc50) failed: No such file or directory (FETCH BODY[]) I'm also seeing errors when replication fails dovecot: dsync-local(username)<bzg3MqjhGFxmFwAAzRvpBw>: Error: dsync(servername): read(attachments-connector(zlib(/usr/home/vmail/mail/username//mdbox/storage/m.413))) failed: read(/usr/home/vmail/attachments/45/42/4542dcf385f6b4a4dc8752b96db1d7ad8a8023d5-ac735007f6bd135c93440100cd1be907[base64:19 b/l]) failed: open(/usr/home/vmail/attachments/45/42/4542dcf385f6b4a4dc8752b96db1d7ad8a8023d5-ac735007f6bd135c93440100cd1be907) failed: No such file or directory (last sent=mail, last recv=mail (EOL)) It is not the case that every replication fail has a corresponding imap access fail. I am running Dovecot 2.3.4 on FreeBSD11.2 and I did not see this error on Dovecot 2.3.1 FreeBSD 10.4. Both installs had the same configuration for Dovecot. Both installs were made from source code and not packages (as the need for the non standard fts and mysql options). During my testing I had the 2.3.1 install receive mail and replicate to the 2.3.4 and that was working fine (except for tcp connection issues which I saw was fixed in the changelog). Unfortunately having gone into testing with real account and mail being sent to the 2.3.4 install I'm seeing the above errors. My clients are using Thunderbird on desktops and Roundcube for webmail. My users report they can see the e-mails fine in their webmail (Roundcube) and only Thunderbird is giving issues. I admit I don't know how this can be the case as both systems use the same account details. In everycase so far there is a file in the hashes directory I have hand crafted the missing file (i.e. link) using ln and this restores access in Thunderbird. Clearly this is an big issue for my install and I'd appreciate any help! At the moment it looks like my course will be to try and script creation (recreation?) of the links from the error logs (I've seen people talking about this online) but that isn't really what I'm after. DOVECOT CONFIG # 2.3.4 (0ecbaf23d): /usr/local/etc/dovecot/dovecot.conf # Pigeonhole version 0.5.4 (60b0f48d) # OS: FreeBSD 11.2-RELEASE-p5 amd64 # Hostname: dovecot01.cwa.uk.com dict { acl = mysql:/usr/local/etc/dovecot/dovecot-dict-sql.conf.ext } disable_plaintext_auth = no doveadm_password = # hidden, use -P to show it first_valid_uid = 145 last_valid_uid = 145 mail_access_groups = mail mail_attachment_dir = /usr/home/vmail/attachments mail_attachment_min_size = 64 k mail_gid = vmail mail_location = mdbox:~/mdbox:INDEX=/indexdisk/indexes/%n mail_plugins = " fts fts_solr acl zlib notify replication" mail_privileged_group = mail mail_uid = vmail managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext namespace { list = yes location = mdbox:%%h/mdbox:INDEXPVT=~/mdbox/shared/%%n prefix = shared/%%n/ separator = / subscriptions = yes type = shared } namespace inbox { inbox = yes location = mailbox Drafts { auto = subscribe special_use = \Drafts } mailbox Junk { auto = subscribe special_use = \Junk } mailbox Sent { auto = subscribe special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { auto = subscribe special_use = \Trash } prefix = type = private } passdb { args = /usr/local/etc/dovecot/dovecot-sql.conf.ext driver = sql } plugin { acl = vfile acl_shared_dict = proxy::acl fts = solr fts_autoindex = yes fts_solr = url=http://localhost:8983/solr/dovecot/ mail_replica = tcp:192.168.0.138:12345 replication_dsync_parameters = -d -l 30 -U sieve = ~/.dovecot.sieve sieve_dir = ~/sieve sieve_duplicate_default_period = 1h sieve_duplicate_max_period = 1d sieve_global_dir = /usr/home/vmail/sieve/global/ sieve_global_path = /usr/home/vmail/default.sieve sieve_vacation_default_period = 1d zlib_save = gz zlib_save_level = 6 } protocols = imap sieve service aggregator { fifo_listener replication-notify-fifo { user = vmail } unix_listener replication-notify { user = vmail } } service auth { unix_listener auth-userdb { mode = 0777 } } service dict { unix_listener dict { mode = 0600 user = vmail } } service doveadm { inet_listener { port = 12345 } } service replicator { process_min_avail = 1 unix_listener replicator-doveadm { mode = 0600 user = vmail } } ssl = no userdb { driver = prefetch } userdb { args = /usr/local/etc/dovecot/dovecot-sql.conf.ext driver = sql } protocol lda { mail_plugins = " fts fts_solr acl zlib notify replication sieve" submission_host = 192.168.0.1:25 } protocol imap { mail_plugins = " fts fts_solr acl zlib notify replication imap_acl imap_zlib" }

1 0

Change default mode for attachment files
by Олег Кривоносов 18 Dec '18

18 Dec '18

Hi I migrated my dovecot server from Maildir to mdbox with saving attachments to external files and enabled SIS a few days ago. Everything works fine except one issue. I have both virtual and system users. Dovecot saves attachments with mode 0600. So I catch such errors for system users: dovecot: lda(wasya): Error: fs-sis: Couldn't read hash file /var/mail/attachments/2e/dc/hashes/2edc6009bc9b6ba38febb581df03986dcaf134d9: Permission denied I want to fix this issue by changing default file mode to 0660 via group policy. I found such feature in the changelog (v2.1.rc2 2012-01-06): lib-fs: Added "mode" parameter to "posix" backend to specify mode for created files/dirs. Unfortunately I can't find any information about this feature in the dovecot documentation. Can I use it to setup mode 0660 for attachments in the dovecot configuration? uname -a Linux diplo.trueconf.ru 4.9.0-6-amd64 #1 SMP Debian 4.9.88-1+deb9u1 (2018-05-07) x86_64 GNU/Linux dovecot --version 2.2.27 (c0f36b0) 10-mail.conf dovecot configuration: mail_access_groups = vmail mail_location = mdbox:~/mdbox mdbox_preallocate_space = yes mdbox_rotate_interval = 1 weeks mdbox_rotate_size = 5 M mail_attachment_dir = /var/mail/attachments mail_attachment_min_size = 32k mail_attachment_fs = sis posix mail_attachment_hash = %{sha1} Thank you

1 0

Possible attack?
by Daniel Miller 18 Dec '18

18 Dec '18

I found an error in my log today... Dec 17 12:03:30 bubba dovecot: imap(user1(a)amfes.com)<23017><VzQFnjx9WNAKO2EC>: Error: fts_solr: received invalid uid '0' Dec 17 12:04:44 bubba dovecot: imap(user2(a)amfes.com)<25004><FeHDSj19i2ysOCn7>: Fatal: master: service(imap): child 25004 killed with signal 11 (core dumps disabled - https://dovecot.org/bugreport.html#coredumps) I've now enabled core dumps (I think) and restarted - if it comes back hopefully I can get a backtrace. But reading that fts_solr message, and some other comments, leads me to wonder - could this be caused by someone/thing trying to authenticate as root? On that theory - I tried doing so via telnet - and received: Dec 17 15:06:02 bubba dovecot: auth: Error: plain(ultradeitytypeperson(a)amfes.com,127.0.0.1,<4kQr0z99UMZ/AAAB>): user not found from any userdbs Dec 17 15:06:02 bubba dovecot: imap: Error: Authenticated user not found from userdb, auth lookup id=3522297857 (auth connected 1 msecs ago, handshake 0 msecs ago, request took 1 msecs, client-pid=29572 client-id=1) I have root's email aliased to a valid user's email. I'm not sure how I'm able to authenticate as root - there isn't a root user defined in my LDAP database and that should be the only auth backend enabled for Dovecot. Or do I need to explicitly block local users from /etc/passwd on the server? The only auth databases shown in doveconf -n: userdb { driver = prefetch } userdb { args = /usr/local/etc/dovecot/dovecot-ldap.conf.ext driver = ldap } passdb { args = /usr/local/etc/dovecot/master-users driver = passwd-file master = yes } passdb { args = /usr/local/etc/dovecot/dovecot-ldap.conf.ext driver = ldap } and "master-users" doesn't list root either. -- Daniel

1 0

Re: ECDSA client question
by Michael A. Peters 18 Dec '18

18 Dec '18

On 12/16/18 7:52 AM, Tributh via dovecot wrote: > > > Am 16.12.18 um 12:13 schrieb Michael A. Peters: >> Hi, for those who have adopted ECDSA, >> >> Are there still any commonly used IMAPS/POP3S clients that still can not >> handle ECDSA certificates? >> >> I know you can set up Dovecot dor dual cert, I am just trying to >> determine if there still is a real world need to. > > Nearly every client can handle ECDSA, but it depends on the size of the > certificate. > I used years ago ECDSA-384bit certificates, which covered most of the > clients. It came to the point to disable RSA in that time, but than came > Android7.0. This Version can only handle ECDSA-256bit certificates or RSA. > > The coverage of Android7.0 is still over 20%. Google reacted fast and > repaired this bug in 7.1, which is still not coming to most of the phones. > > Cheers > Torsten > Wow - My phone is running Android 6, I just checked with Dad - his phone (Motorola) is running Android 7.0 - the version with the bug. We don't replace phones just because new versions are available, we replace them when they stop working, and when we do we usually get refurbished because we hate how much electronic waste is in the world. I have to admit, the tin foil hat of mine just got an alert. We know there are unexplained constants in the NIST curves including P-256 - what if NSA was partially responsible for this bug (back room deal to avoid anti-trust prosecution, similar deal with IBM was made in the 70s I believe also involving cryptography) so that Android apps that use ECDSA (beyond just the mail client, e.g. chat apps) would use P-256 for compatibility and are maybe vulnerable to MITM for the key exchange. I want Ed25519 now.

2 1

Overrideing pop delete?
by ＠lbutlr 17 Dec '18

17 Dec '18

Is it possible to override the POP3 delete on download command and make sure that messages stay on the server for at least X hours or X days? It is important that the messages be around long enough to hit a snapshot cycle (using rsnapshot to backup ever hour). -- Greedo didn't shoot first, motherfucker!

3 7

Bug in IDLE implementation for virtual mailbox
by Pali Rohár 17 Dec '18

17 Dec '18

Hello! I found bug in Dovecot's IDLE implementation when virtual mailbox is in use. IDLE does not notify about new emails when email appears in newly created mailbox and IDLE was issued in virtual folder which matches "*" wildcard and that mailbox was created after opening virtual mailbox. This problem is present in version 2.2.34 which is available in Debian Stretch system with backports. Reproducer: 1. Create virtual "All" mailbox in Gmail-like style: $ cat All/dovecot-virtual * -Drafts -Spam -Trash ALL 2. Ensure that (real non-virtual) mailbox "Test" does not exist. 3. Create sieve rule which deliver some email to "Test" mailbox. require [ "fileinto", "mailbox" ]; ... fileinto :create "Test"; 4. Open dovecot imap connection, select virtual "All" mailbox and then enter IDLE command. 4. Send email which matches that sieve filter. Email will be processed by dovecot sieve. As "Test" mailbox does not exist, dovecot sieve would first create it and then deliver email into it. Now dovecot imap should notify IDLE client that new message into virtual "All" mailbox was delivered (as it collects emails from all - * - mailboxes). But dovecot for some unknown reason does not notify via IDLE that there is a new email. To get notifications, it is needed to re-open that "All" mailbox again. -- Pali Rohár pali.rohar(a)gmail.com

2 4

Downgrade dovecot if required
by Durga Prasad Malyala 17 Dec '18

17 Dec '18

Hello all, I have version 2.3.3-2 of dovecot and could see version 2.3.4-2 available from the repos. How is feedback after upgrade to 2.3.4-2? Any issues? Can I revert back to older version if I face any problems? Cheers/DP

2 1

ssh_dh?
by Daniel Miller 17 Dec '18

17 Dec '18

Don't know if this was corrected in 2.3.4 (haven't upgraded yet but didn't see it in the notes) - but in 2.3.3 I see this in my log: imap-login: Error: Diffie-Hellman key exchange requested, but no DH parameters provided. Set ssh_dh=</path/to/dh.pem So...either there's an undocumented feature of SSH-over-IMAP (that's Dovecot - always on the cutting edge!) or someone had a coffee shortage during a coding session... -- Daniel

5 5

Sieve scripts not backed up
by Marc Weustink 17 Dec '18

17 Dec '18

Hi all. I try to backup out sieve scripts through doveadm -o stats_writer_socket_path= backup -R -u marc -N tcp:<remote.host>:4191 All mail is backed up but no scripts. What am I doing wrong ? Thanks Marc doveconf -n # 2.3.4 (0ecbaf23d): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.4 (60b0f48d) # OS: Linux 4.4.0-137-generic x86_64 Ubuntu 16.04.5 LTS autofs # Hostname: xxx dict { acl = pgsql:/etc/dovecot/dovecot-dict-sql-local.conf.ext } doveadm_password = # hidden, use -P to show it mail_debug = yes mail_gid = vmail mail_home = /home/mail/backup/%n mail_location = maildir:/home/mail/backup/%n/mail mail_uid = vmail managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext namespace Shared { location = maildir:/home/mail/backup/Common/mail:INDEXPVT=/home/mail/backup/%n/mail/common prefix = Shared/ separator = / subscriptions = no type = public } namespace Users { list = children location = maildir:/home/mail/backup/%%n/mail:INDEXPVT=/home/mail/backup/%n/mail/shared/%%n prefix = Users/%%n/ separator = / subscriptions = no type = shared } namespace inbox { inbox = yes location = mailbox Drafts { special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Sent { special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { special_use = \Trash } prefix = separator = / type = private } passdb { args = /etc/dovecot/dovecot-sql.conf.ext driver = sql } plugin { acl = vfile acl_shared_dict = proxy::acl sieve = file:~/sieve;active=~/.dovecot.sieve } protocols = sieve service auth { unix_listener auth-userdb { mode = 0777 } } service dict { unix_listener dict { group = vmail user = vmail } } ssl = no userdb { args = /etc/dovecot/dovecot-sql.conf.ext driver = sql }

2 1

Upgrade to 2.3.1 has failed
by C. Andrews Lavarre 17 Dec '18

17 Dec '18

Problem: We had Dovecot v2.2 working just fine under openSUSE Leap 42.3. But we upgraded openSUSE to Leap 15.0. In the process, Dovecot got upgraded from 2.2 to 2.3.1. It no longer works and I haven't figured out how to downgrade to the older working version. The key issue seems to be the change to requiring dh.pem and changing s sl_protocols to ssl_min_protocols. I think I've navigated both correctly, but it still doesn't work. The error is auth: Error: stats: open(old-stats-user) failed: Permission denied as a consequence of which we get imap-login: Error: Failed to initialize SSL server context: Can't load SSL certificate: There is no valid PEM certificate. We have followed the instructions at https://wiki.dovecot.org/S SL/DovecotConfiguration 1. We have created /etc/dovecot/dh.pem (yes it took five hours) 2. We have edited 10-ssl.conf as directed by the Wiki: ssl = yes ssl_cert = /etc/certbot/live/privustech.com/fullchain.pem ssl_key = /etc/certbot/live/privustech.com/privkey.pem ssl_dh = /etc/dovecot/dh.pem #(yes, it took five hours to create...) ssl_min_protocol = TLSv1 ssl_cipher_list = ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@STRENGTH ssl_prefer_server_ciphers = no 3. We have checked 10-ssl.conf against the 2.3 default at https://github.com/dovecot/core/blob/master/doc/example-config/conf.d/10-ss… 4. We do NOT include the less than (<) symbol before the paths because then dovecot fails to load complaining it cannot find the files. 5. we have checked all the pem keys, certificates, and dh files with cat, they all exist and are in the expected hash format. 6. We have followed the instructions to set their permissions root:root 0444 and 0400 accordingly. 7. We have rebooted the host. Any help or clues would be most appreciated. Kind regards, Andy

7 20

ECDSA client question
by Michael A. Peters 16 Dec '18

16 Dec '18

Hi, for those who have adopted ECDSA, Are there still any commonly used IMAPS/POP3S clients that still can not handle ECDSA certificates? I know you can set up Dovecot dor dual cert, I am just trying to determine if there still is a real world need to.

2 1

Plugins mailboxalias subfolders
by Marc Roos 16 Dec '18

16 Dec '18

This plugin does not work anymore when subfolders are created. https://wiki2.dovecot.org/Plugins/MailboxAlias

1 0

mailbox locking
by Victor Sudakov 16 Dec '18

16 Dec '18

Dear Colleagues, I use exim's appendfile transport, procmail and a local mutt on my system, they all (to my knowledge) use lockfiles when working with mboxes. However, `doveconf | grep lock` says dotlock_use_excl = yes lock_method = fcntl mail_max_lock_timeout = 0 mbox_dotlock_change_timeout = 2 mins mbox_lock_timeout = 5 mins mbox_read_locks = fcntl mbox_write_locks = dotlock fcntl pop3_lock_session = no Do I need to change anything in dovecot's default locking setup? Does it still use lockfiles on mboxes or not? There are some contradictory parameters IMHO. -- Victor Sudakov, VAS4-RIPE, VAS47-RIPN 2:5005/49@fidonet http://vas.tomsk.ru/

1 1