Email from vcenter 6.7 fails to deliver

sendmailvmware-vcenter

Desired end state: I would like to receive alert email from vcenter 6.7.

Specific problem: After configuring vcenter 6.7 (in the UI) with an SMTP server that works as tested from the vcenter shell, mail does not get delivered.

Specific error in /var/log/vmware/messages:

2019-11-15T02:20:02.582561+00:00 vcenter sendmail[1181]:
xAE99Q0S013190: to=foo@bar.com, delay=16:49:55,
xdelay=00:00:00, mailer=esmtp, pri=1562265,
relay=aspmx3.googlemail.com., dsn=4.0.0, stat=Deferred: Connection
timed out with aspmx3.googlemail.com.

SMTP test from vcenter shell: created a text file with SMTP commands and used nc to send them port 25 of the SMTP server, it worked.

Attempted solution: vmware kb article

Solution does not work as the binary SuSEconfig doesn't exist in version 6.7.

Best Answer

You need to edit /etc/mail/sendmail.mc and add the following line:

FEATURE(`nocanonify`)

this will stop sendmail from looking up the mail server via MX records and just use the one you specified.

Restart sendmail after you've made the change.

Related Solutions

Sendmail: SMTP host name lookup failure

I'm going out on a bit of a limb here, but I think the problem is your remote host ...

getmxrr(smtp-server.nycap.rr.com, droplocalhost=1)
getmxrr: res_search(smtp-server.nycap.rr.com) failed (errno=110, h_errno=2)
<zeno@biyg.net>... Deferred: Name server: smtp-server.nycap.rr.com: host name lookup failure

It looks like res_search is the culprit here and what it's searching for (smtp-server.nycap.rr.com) is producing the error. According to netdb.h (I think) that error is either non-authoritative host or SRVFAIL.

Checking dns, it does look like something's wrong with that host (please forgive the use of nslookup) :

Non-authoritative answer:
Name:   smtp-server.nycap.rr.com
Address: 75.180.132.33

nslookup
> set q=ptr
> 75.180.132.33

Non-authoritative answer:
33.132.180.75.in-addr.arpa      name = cdptpa-omtalb.mail.rr.com.

I want to say it looks like a forward/reverse mismatch, but I could be wrong. It could just be one bad entry in their mailcluster. I'm thinking the reason that it works in the debug mode is that ruleset 3 is skipped and part of that ruleset is doing reverse lookups on the destination mailserver.

You might be able to solve this with a mailertable, that would go a ways towards fingering DNS info as the culprit. Take a look at this -- Solving hostname lookup failures in sendmail

Debugging sendmail – dsn=5.0.0

Sendmail: Sending outgoing test message in verbose/debug mode

As root you may send a test message in verbose mode.
You should get full transcript of SMTP session to the remote SMTP server.

(echo: subject: test; echo) | /usr/sbin/sendmail -v -Am -i user@example.net

You may add additional debug/tracking command line options:
-d8.20 - tracking DNS queuries
-d60.5 - tracking maps (databases) queries

Best Answer

Related Solutions

Sendmail: SMTP host name lookup failure

Debugging sendmail – dsn=5.0.0

Sendmail: Sending outgoing test message in verbose/debug mode

Related Topic