Posted by From previous article, you can configure and validate DKIM records on Zimbra which is used to increase email reputation. The configuration will increase reputation for outgoing email. But, how to enable DKIM/DomainKeys checking for incoming connection?
By enable DKIM/DomainKeys checking, you can reject every incoming email who did not have DKIM/DomainKeys. By default, Zimbra only configure OpenDKIM as signer. For configure OpenDKIM as verifier, you can follow these step
# Open openDKIM configuration
su - zimbra vi /opt/zimbra/conf/opendkim.conf.in
adjust below configuration. save and exit
On-NoSignature reject Mode sv
# Restart OpenDKIM
zmopendkimctl restart
The following is example log when receive email from domain who did not have DKIM
Mar 18 15:10:13 mail postfix/cleanup[22424]: 64728441B96: milter-reject: END-OF-MESSAGE from localhost[127.0.0.1]: 5.7.0 no DKIM signature data; from=<xxxx@xxxxxx.xxx> to=<xxxx@xxxxxx.xx.xx> proto=ESMTP helo=<xxx.xxxxx.xxx> Mar 18 15:10:13 mail postfix/smtp[23944]: 94BC4441B99: to=<xxxx@xxxxx.xx.xx>, relay=127.0.0.1[127.0.0.1]:10030, delay=42, delays=42/0.02/0.02/0.09, dsn=5.7.0, status=bounced (host 127.0.0.1[127.0.0.1] said: 550 5.7.0 no DKIM signature data (in reply to end of DATA command))
Good luck and hopefully useful 🙂
Hi
it is not working in ZCS 8.6 I have tested as you mentioned.
Hello,
Are you have any information on log about why the configuration not working?
I configured zimbra 8.7 to work with DKIM.
External messages with correct signature are verified and processed.
Internal messages without signature are rejected
External messages without signature are accepted.
Here the log of the connection from an external address without signature
Jul 10 15:57:15 mail postfix/postscreen[6744]: CONNECT from [79.52.221.58]:34580 to [10.55.0.40]:25
Jul 10 15:57:15 mail postfix/postscreen[6744]: PASS OLD [79.52.221.58]:34580
Jul 10 15:57:15 mail postfix/smtpd[29516]: connect from host58-221-dynamic.52-79-r.retail.telecomitalia.it[79.52.221.58]
Jul 10 15:57:51 mail postfix/smtpd[29516]: NOQUEUE: filter: RCPT from host58-221-dynamic.52-79-r.retail.telecomitalia.it[79.52.221.58]: : Sender address triggers FILTER smtp-amavis:[127.0.0.1]:10026; from= to= proto=SMTP helo=
Jul 10 15:57:51 mail postfix/smtpd[29516]: NOQUEUE: filter: RCPT from host58-221-dynamic.52-79-r.retail.telecomitalia.it[79.52.221.58]: : Sender address triggers FILTER smtp-amavis:[127.0.0.1]:10024; from= to= proto=SMTP helo=
Jul 10 15:57:52 mail postfix/smtpd[29516]: 456DFF8006A: client=host58-221-dynamic.52-79-r.retail.telecomitalia.it[79.52.221.58]
Jul 10 15:57:59 mail postfix/postscreen[6744]: CONNECT from [10.55.0.31]:59973 to [10.55.0.40]:25
Jul 10 15:57:59 mail postfix/postscreen[6744]: WHITELISTED [10.55.0.31]:59973
Jul 10 15:57:59 mail postfix/smtpd[18048]: connect from prtg.systeamus.com[10.55.0.31]
Jul 10 15:57:59 mail postfix/smtpd[18048]: disconnect from prtg.systeamus.com[10.55.0.31] ehlo=1 quit=1 commands=2
Jul 10 15:58:11 mail zmconfigd[2368]: Fetching All configs
Jul 10 15:58:11 mail zmconfigd[2368]: All configs fetched in 0.05 seconds
Jul 10 15:58:15 mail zmconfigd[2368]: Watchdog: service antivirus status is OK.
Jul 10 15:58:15 mail zmconfigd[2368]: All rewrite threads completed in 0.03 sec
Jul 10 15:58:15 mail zmconfigd[2368]: All restarts completed in 0.00 sec
Jul 10 15:58:35 mail postfix/cleanup[18042]: 456DFF8006A: message-id=
Jul 10 15:58:35 mail postfix/qmgr[5602]: 456DFF8006A: from=, size=374, nrcpt=1 (queue active)
Jul 10 15:58:35 mail amavis[13009]: (13009-07) ESMTP [127.0.0.1]:10024 /opt/zimbra/data/amavisd/tmp/amavis-20170710T115046-13009-OGOthOah: -> SIZE=374 Received: from mail.cloak.me ([127.0.0.1]) by localhost (mail.cloak.me [127.0.0.1]) (amavisd-new, port 10024) with ESMTP for ; Mon, 10 Jul 2017 15:58:35 -0700 (PDT)
Jul 10 15:58:35 mail amavis[13009]: (13009-07) Checking: 73CLjTFd19Vz [79.52.221.58] ->
Jul 10 15:58:36 mail postfix/amavisd/smtpd[18915]: connect from localhost[127.0.0.1]
Jul 10 15:58:36 mail postfix/amavisd/smtpd[18915]: D9115F80083: client=localhost[127.0.0.1]
Jul 10 15:58:36 mail postfix/cleanup[18042]: D9115F80083: message-id=
Jul 10 15:58:36 mail postfix/amavisd/smtpd[18915]: disconnect from localhost[127.0.0.1] ehlo=1 mail=1 rcpt=1 data=1 quit=1 commands=5
Jul 10 15:58:36 mail postfix/qmgr[5602]: D9115F80083: from=, size=1105, nrcpt=1 (queue active)
Jul 10 15:58:36 mail amavis[13009]: (13009-07) 73CLjTFd19Vz FWD from -> , BODY=7BIT 250 2.0.0 from MTA(smtp:[127.0.0.1]:10025): 250 2.0.0 Ok: queued as D9115F80083
Jul 10 15:58:36 mail amavis[13009]: (13009-07) Passed CLEAN {RelayedInbound}, [79.52.221.58]:34580 [79.52.221.58] -> , Queue-ID: 456DFF8006A, Message-ID: , mail_id: 73CLjTFd19Vz, Hits: 2.816, size: 374, queued_as: D9115F80083, 1774 ms
Jul 10 15:58:36 mail postfix/smtp[18913]: 456DFF8006A: to=, orig_to=, relay=127.0.0.1[127.0.0.1]:10024, delay=57, delays=55/0.02/0.01/1.8, dsn=2.0.0, status=sent (250 2.0.0 from MTA(smtp:[127.0.0.1]:10025): 250 2.0.0 Ok: queued as D9115F80083)
Jul 10 15:58:36 mail postfix/qmgr[5602]: 456DFF8006A: removed
Jul 10 15:58:37 mail postfix/lmtp[18916]: D9115F80083: to=, relay=mail.cloak.me[10.55.0.40]:7025, delay=0.2, delays=0.01/0.02/0.11/0.06, dsn=2.1.5, status=sent (250 2.1.5 Delivery OK)
Jul 10 15:58:37 mail postfix/qmgr[5602]: D9115F80083: removed
Jul 10 15:58:37 mail postfix/smtpd[29516]: disconnect from host58-221-dynamic.52-79-r.retail.telecomitalia.it[79.52.221.58] helo=1 mail=1 rcpt=1 data=1 quit=1 unknown=0/2 commands=5/7
(END)
Here the opendkim config
UserID zimbra:zimbra
UMask 022
Socket %%zimbraInetMode%%:8465@[%%zimbraLocalBindAddress%%]
PidFile /opt/zimbra/log/opendkim.pid
LDAPBindUser uid=zmpostfix,cn=appaccts,cn=zimbra
LDAPBindPassword @@ldap_postfix_password@@
LDAPUseTLS @@ldap_starttls_supported@@
LDAPTimeout 30
LDAPKeepaliveIdle 240
LDAPKeepaliveProbes 10
LDAPKeepaliveInterval 30
SigningTable @@opendkim_signingtable_uri@@
KeyTable @@opendkim_keytable_uri@@
#Canonicalization relaxed/relaxed
Canonicalization relaxed/simple
ReportAddress @@av_notify_user@@
SignHeaders message-id,date,from,mime-version,to
On-BadSignature quarantine
On-DNSError tempfail
On-InternalError tempfail
On-NoSignature reject
On-Security tempfail
AllowSHA1Only no
AlwaysAddARHeader no
AuthservIDWithJobId yes
AutoRestart yes
AutoRestartCount 20
AutoRestartRate 10/1h
Background Yes
ClockDrift 300
DisableCryptoInit yes
DNSTimeout 10
DomainKeysCompat no
EnableCoredumps yes
FixCRLF no
MaximumHeaders 65536
Minimum 0
Mode sv
MultipleSignatures no
NoHeaderB no
RequireSafeKeys Yes
SignatureAlgorithm rsa-sha256
SignatureTTL 0
StrictHeaders no
StrictTestMode no
SubDomains no
InternalHosts file:/opt/zimbra/conf/opendkim-localnets.conf
ExternalIgnoreList file:/opt/zimbra/conf/opendkim-localnets.conf
PeerList file:/opt/zimbra/conf/opendkim-localnets.conf
SendReports yes
Diagnostics yes
LogWhy yes
Quarantine yes
ResolverTracing no
Syslog yes
SyslogFacility LOCAL0
SyslogSuccess no
SoftwareHeader yes
TemporaryDirectory /opt/zimbra/data/tmp
KeepTemporaryFiles no
MilterDebug 0
~
~
Hello,
I am not find reject on your log. By default, your IP address be supposed as part from opendkim-localnets
Hi,
this is the problem on the public IP (external)
the email not signed passes without any problem
Here the segment note Ip address source is 79.52.221.58
Jul 10 15:32:13 mail postfix/cleanup[31026]: 23736F800B4: message-id=
Jul 10 15:32:13 mail postfix/qmgr[5602]: 23736F800B4: from=, size=395, nrcpt=1 (queue active)
Jul 10 15:32:13 mail amavis[29181]: (29181-10) ESMTP [127.0.0.1]:10024 /opt/zimbra/data/amavisd/tmp/amavis-20170710T125611-29181-aNnefojn: -> SIZE=395 Received: from mail.cloak.me ([127.0.0.1]) by localhost (mail.cloak.me [127.0.0.1]) (amavisd-new, port 10024) with ESMTP for ; Mon, 10 Jul 2017 15:32:13 -0700 (PDT)
Jul 10 15:32:13 mail amavis[29181]: (29181-10) Checking: oAeU9-jXutqQ [79.52.221.58] ->
Jul 10 15:32:14 mail postfix/amavisd/smtpd[26286]: connect from localhost[127.0.0.1]
Jul 10 15:32:14 mail postfix/amavisd/smtpd[26286]: 0EB75F804AF: client=localhost[127.0.0.1]
Jul 10 15:32:14 mail postfix/cleanup[31608]: 0EB75F804AF: message-id=
Jul 10 15:32:14 mail postfix/qmgr[5602]: 0EB75F804AF: from=, size=1154, nrcpt=1 (queue active)
Jul 10 15:32:14 mail postfix/amavisd/smtpd[26286]: disconnect from localhost[127.0.0.1] ehlo=1 mail=1 rcpt=1 data=1 quit=1 commands=5
Jul 10 15:32:14 mail amavis[29181]: (29181-10) oAeU9-jXutqQ FWD from -> , BODY=7BIT 250 2.0.0 from MTA(smtp:[127.0.0.1]:10025): 250 2.0.0 Ok: queued as 0EB75F804AF
Jul 10 15:32:14 mail amavis[29181]: (29181-10) Passed CLEAN {RelayedInbound}, [79.52.221.58]:34326 [79.52.221.58] -> , Queue-ID: 23736F800B4, Message-ID: , mail_id: oAeU9-jXutqQ, Hits: 4.224, size: 395, queued_as: 0EB75F804AF, 301 ms
Jul 10 15:32:14 mail postfix/smtp[31029]: 23736F800B4: to=, orig_to=, relay=127.0.0.1[127.0.0.1]:10024, delay=104, delays=104/0/0.01/0.3, dsn=2.0.0, status=sent (250 2.0.0 from MTA(smtp:[127.0.0.1]:10025): 250 2.0.0 Ok: queued as 0EB75F804AF)
Jul 10 15:32:14 mail postfix/qmgr[5602]: 23736F800B4: removed
Jul 10 15:32:14 mail postfix/lmtp[31084]: 0EB75F804AF: to=, relay=mail.cloak.me[10.55.0.40]:7025, delay=0.16, delays=0.01/0/0.11/0.05, dsn=2.1.5, status=sent (250 2.1.5 Delivery OK)
Jul 10 15:32:14 mail postfix/qmgr[5602]: 0EB75F804AF: removed
Jul 10 15:32:15 mail postfix/smtpd[21644]: disconnect from host58-221-dynamic.52-79-r.retail.telecomitalia.it[79.52.221.58] helo=1 mail=1 rcpt=1/2 data=1 quit=1 commands=5/6
Here instead the rejection before I added added PeerList into the config file. IP address 10.50.50.6 is internal (was already in the zimbra file opendkim-localnets.com)
Jul 10 15:01:01 mail amavis[31728]: (31728-08) ESMTP [127.0.0.1]:10026 /opt/zimbra/data/amavisd/tmp/amavis-20170710T103155-31728-k5JD6sVy: -> Received: from mail.cloak.me ([127.0.0.1]) by localhost (mail.cloak.me [127.0.0.1]) (amavisd-new, port 10026) with ESMTP for ; Mon, 10 Jul 2017 15:01:01 -0700 (PDT)
Jul 10 15:01:01 mail amavis[31728]: (31728-08) Checking: n41o61fbF9K8 ORIGINATING/MYNETS [10.50.50.6] ->
Jul 10 15:01:01 mail postfix/dkimmilter/smtpd[5776]: connect from localhost[127.0.0.1]
Jul 10 15:01:01 mail postfix/dkimmilter/smtpd[5776]: A2650F804AF: client=localhost[127.0.0.1]
Jul 10 15:01:01 mail postfix/cleanup[6914]: A2650F804AF: message-id=
Jul 10 15:01:01 mail opendkim[5801]: A2650F804AF: no signing table match for ‘luigi@luigi.com’
Jul 10 15:01:01 mail opendkim[5801]: A2650F804AF: no signature data
Jul 10 15:01:01 mail postfix/cleanup[6914]: A2650F804AF: milter-reject: END-OF-MESSAGE from localhost[127.0.0.1]: 5.7.0 no DKIM signature data; from= to= proto=ESMTP helo=
Jul 10 15:01:01 mail postfix/dkimmilter/smtpd[5776]: disconnect from localhost[127.0.0.1] ehlo=1 mail=1 rcpt=1 data=0/1 quit=1 commands=4/5
Jul 10 15:01:01 mail amavis[31728]: (31728-08) Negative SMTP response to data-dot (): 550 5.7.0 no DKIM signature data, dt: 86.9 ms
Jul 10 15:01:01 mail amavis[31728]: (31728-08) (!)n41o61fbF9K8 FWD from -> , BODY=7BIT 550 5.7.0 from MTA(smtp:[127.0.0.1]:10030): 550 5.7.0 no DKIM signature data
Jul 10 15:01:01 mail amavis[31728]: (31728-08) Blocked MTA-BLOCKED {RejectedInternal}, ORIGINATING/MYNETS LOCAL [10.50.50.6]:44648 -> , Queue-ID: 5C658F800B4, Message-ID: , mail_id: n41o61fbF9K8, Hits: -, size: 342, 173 ms
Jul 10 15:01:01 mail postfix/smtp[5749]: 5C658F800B4: to=, orig_to=, relay=127.0.0.1[127.0.0.1]:10026, delay=19, delays=19/0/0/0.17, dsn=5.7.0, status=bounced (host 127.0.0.1[127.0.0.1] said: 550 5.7.0 id=31728-08 – Rejected by next-hop MTA on relaying, from MTA(smtp:[127.0.0.1]:10030): 550 5.7.0 no DKIM signature data (in reply to end of DATA command))
Hello Luigi,
What your domain on Zimbra? please masking/change your domain on the log with another domain for troubleshoot
The driving crazy factor is that the internal ip execute DKIM and get rejected because there is no signature, while the external ip does not even get processed.
Any idea?
Thanks
Hi Iman,
my domain is cloak.me, but I do not know how to edit the post.
Thanks
Luigi
Hi Luigi,
If your domain is cloak.me, your email from luigi@luigi.com have no DKIM so that rejected
Hi Iman,
Luigi@luigi.com does not have signature and he get rejected, BUT is coming from a trusted internal IP address where was supposedly not to be checked.
At the same time if I do the same (pluto@www.pluto.com with no signature) from a public ipaddress opendkim will not even attempt to check the signature and will accept the message.
ul 10 13:53:29 mail postfix/smtpd[25414]: NOQUEUE: filter: RCPT from host58-221-dynamic.52-79-r.retail.telecomitalia.it[79.52.221.58]: : Sender address triggers FILTER smtp-amavis:[127.0.0.1]:10026; from= to= proto=SMTP helo=
Jul 10 13:53:29 mail postfix/smtpd[25414]: NOQUEUE: filter: RCPT from host58-221-dynamic.52-79-r.retail.telecomitalia.it[79.52.221.58]: : Sender address triggers FILTER smtp-amavis:[127.0.0.1]:10024; from= to= proto=SMTP helo=
Jul 10 13:53:30 mail postfix/smtpd[25414]: 24730F8006A: client=host58-221-dynamic.52-79-r.retail.telecomitalia.it[79.52.221.58]
Jul 10 13:53:42 mail postfix/anvil[1715]: statistics: max connection rate 1/60s for (smtpd:79.52.221.58) at Jul 10 13:51:58
Jul 10 13:53:42 mail postfix/anvil[1715]: statistics: max connection count 1 for (smtpd:79.52.221.58) at Jul 10 13:51:58
Jul 10 13:53:42 mail postfix/anvil[1715]: statistics: max cache size 1 at Jul 10 13:51:58
Jul 10 13:53:59 mail postfix/postscreen[6744]: CONNECT from [10.55.0.31]:62362 to [10.55.0.40]:25
Jul 10 13:53:59 mail postfix/postscreen[6744]: WHITELISTED [10.55.0.31]:62362
Jul 10 13:53:59 mail postfix/smtpd[15486]: connect from prtg.systeamus.com[10.55.0.31]
Jul 10 13:53:59 mail postfix/smtpd[15486]: disconnect from prtg.systeamus.com[10.55.0.31] ehlo=1 quit=1 commands=2
Jul 10 13:54:04 mail postfix/cleanup[16864]: 24730F8006A: message-id=
Jul 10 13:54:04 mail postfix/qmgr[5602]: 24730F8006A: from=, size=363, nrcpt=1 (queue active)
Jul 10 13:54:04 mail amavis[29175]: (29175-03) ESMTP [127.0.0.1]:10024 /opt/zimbra/data/amavisd/tmp/amavis-20170710T125610-29175-CP4Gyf71: -> SIZE=363 Received: from mail.cloak.me ([127.0.0.1]) by localhost (mail.cloak.me [127.0.0.1]) (amavisd-new, port 10024) with ESMTP for ; Mon, 10 Jul 2017 13:54:04 -0700 (PDT)
Jul 10 13:54:05 mail amavis[29175]: (29175-03) Checking: fR3hT8awOTMI [79.52.221.58] ->
Jul 10 13:54:05 mail postfix/amavisd/smtpd[17179]: connect from localhost[127.0.0.1]
Jul 10 13:54:05 mail postfix/amavisd/smtpd[17179]: 7F402F80083: client=localhost[127.0.0.1]
Jul 10 13:54:05 mail postfix/cleanup[16864]: 7F402F80083: message-id=
Jul 10 13:54:05 mail postfix/qmgr[5602]: 7F402F80083: from=, size=1017, nrcpt=1 (queue active)
Jul 10 13:54:05 mail postfix/amavisd/smtpd[17179]: disconnect from localhost[127.0.0.1] ehlo=1 mail=1 rcpt=1 data=1 quit=1 commands=5
Jul 10 13:54:05 mail amavis[29175]: (29175-03) fR3hT8awOTMI FWD from -> , BODY=7BIT 250 2.0.0 from MTA(smtp:[127.0.0.1]:10025): 250 2.0.0 Ok: queued as 7F402F80083
Jul 10 13:54:05 mail amavis[29175]: (29175-03) Passed CLEAN {RelayedInbound}, [79.52.221.58]:54517 [79.52.221.58] -> , Queue-ID: 24730F8006A, Message-ID: , mail_id: fR3hT8awOTMI, Hits: 0.104, size: 363, queued_as: 7F402F80083, 576 ms
Jul 10 13:54:05 mail postfix/smtp[17173]: 24730F8006A: to=, orig_to=, relay=127.0.0.1[127.0.0.1]:10024, delay=83, delays=83/0.03/0.01/0.57, dsn=2.0.0, status=sent (250 2.0.0 from MTA(smtp:[127.0.0.1]:10025): 250 2.0.0 Ok: queued as 7F402F80083)
Jul 10 13:54:05 mail postfix/qmgr[5602]: 24730F8006A: removed
Jul 10 13:54:05 mail postfix/lmtp[17180]: 7F402F80083: to=, relay=mail.cloak.me[10.55.0.40]:7025, delay=0.2, delays=0.01/0.02/0.11/0.06, dsn=2.1.5, status=sent (250 2.1.5 Delivery OK)
Jul 10 13:54:05 mail postfix/qmgr[5602]: 7F402F80083: removed
Jul 10 13:54:23 mail postfix/smtpd[25414]: disconnect from host58-221-dynamic.52-79-r.retail.telecomitalia.it[79.52.221.58] helo=1 mail=1 rcpt=1 data=1 quit=1 unknown=0/2 commands=5/7
Try again
Jul 10 13:54:05 mail postfix/qmgr[5602]: 7F402F80083: from=, size=1017, nrcpt=1 (queue active)
Jul 10 13:54:05 mail postfix/amavisd/smtpd[17179]: disconnect from localhost[127.0.0.1] ehlo=1 mail=1 rcpt=1 data=1 quit=1 commands=5
Jul 10 13:54:05 mail amavis[29175]: (29175-03) fR3hT8awOTMI FWD from -> , BODY=7BIT 250 2.0.0 from MTA(smtp:[127.0.0.1]:10025): 250 2.0.0 Ok: queued as 7F402F80083
Jul 10 13:54:05 mail amavis[29175]: (29175-03) Passed CLEAN {RelayedInbound}, [79.52.221.58]:54517 [79.52.221.58] -> , Queue-ID: 24730F8006A, Message-ID: , mail_id: fR3hT8awOTMI, Hits: 0.104, size: 363, queued_as: 7F402F80083, 576 ms
Jul 10 13:54:05 mail postfix/smtp[17173]: 24730F8006A: to=, orig_to=, relay=127.0.0.1[127.0.0.1]:10024, delay=83, delays=83/0.03/0.01/0.57, dsn=2.0.0, status=sent (250 2.0.0 from MTA(smtp:[127.0.0.1]:10025): 250 2.0.0 Ok: queued as 7F402F80083)
Jul 10 13:54:05 mail postfix/qmgr[5602]: 24730F8006A: removed
Jul 10 13:54:05 mail postfix/lmtp[17180]: 7F402F80083: to=, relay=mail.cloak.me[10.55.0.40]:7025, delay=0.2, delays=0.01/0.02/0.11/0.06, dsn=2.1.5, status=sent (250 2.1.5 Delivery OK)
For some reason log parts with name are missing.
Hi Luigi,
Maybe you can sent PM to me from this page : https://imanudin.net/contact/
I configured zimbra 8.0.7 to work with DKIM.
Internal message rejected which is forwarding stetted by user or admin.
“host 127.0.0.1[127.0.0.1] said: 550 5.7.0
id=30989-05 – Rejected by next-hop MTA on relaying, from
MTA(smtp:[127.0.0.1]:10030): 550 5.7.0 no DKIM signature data (in reply to end of DATA command)”
Hi Mitesh Kuvariya,
Please make sure your domain has been configured DKIM and publish public key on your DNS too
Hi Imanudin,
Can we block the domain only fail dkim verfication. Because we have lot of cusotmers which don’t have dkim signature in their domain so if we put reject on non signature everything will fail.
Hello,
I have no idea. Maybe you can apply SPF checking instead of DKIM 🙂 : https://imanudin.net/2016/03/11/zimbra-tips-how-to-enable-spf-checking-for-incoming-connection/
Hi Iman,
I have a peculiar problem in Zimbra 8.8.12 – All of a sudden, OpenDKIM does not start with the error Connection to LDAP failed. ON further investigation, I found that it is asking for TLS connect to the LDAP server but for some reason, the LDAP does not allow TLS connect. How do I check if TLS is enabled for LDAP and how do I allow LDAP to accept TLS connections?
Hi Krish,
Please check this wiki: https://wiki.zimbra.com/wiki/Unable_to_create_a_successful_TLS_connection_to_the_ldap_masters#Method_3:_Disabling_all_TLS_connections. Zero is mean disabled
Hello Iman,
Is there a whitelist for this dkim check?
Tks.
Hi Igor,
currently unavailable