From queszama at yahoo.in Thu Sep 1 04:35:38 2016 From: queszama at yahoo.in (Zama Ques) Date: Thu, 1 Sep 2016 04:35:38 +0000 (UTC) Subject: Sendmail Issue References: <946758326.2662064.1472704538546.ref@mail.yahoo.com> Message-ID: <946758326.2662064.1472704538546@mail.yahoo.com> Need some clarification on Mail Settings. We are managing around hundreds of applications. These applications runs on Linux based hosts and used to send mails to users based on user registration at site and other actions. We have Sendmail configured on these Linux servers to relay mails to destination mailbox. The following setting is being used in sendmail.cf to forward mails to relay mail server. DSesmtp:xmail.example.com This is fine for me. But on some servers , I can see only sendmail is running but the above settings is not enabled. But still mails are going through this server. I tried to send mails to Yahoo and GMAIL accounts and mails are successfully getting delivered. Aug 31 03:36:12 vmprod sendmail[23396]: u7V7aCMr023396: from=, size=534, class=0, nrcpts=1, msgid=<201608310736.u7V7aCee023393 at vmprod.wiley.com>, proto=ESMTP, daemon=MTA, *relay=localhost [127.0.0.1]* Aug 31 03:36:12 vmprod sendmail[23393]: u7V7aCee023393: to=queszama at yahoo.in, ctladdr=admin (35014/10), delay=00:00:00, xdelay=00:00:00, mailer=relay, pri=30220, relay=[127.0.0.1] [127.0.0.1], dsn=2.0.0, stat=Sent (u7V7aCMr023396 Message accepted for delivery) Aug 31 03:36:13 vmprod sendmail[23398]: STARTTLS=client, relay=mx-apac.mail.gm0.yahoodns.net., version=TLSv1/SSLv3, verify=FAIL, cipher=RC4-SHA, bits=128/128 Aug 31 03:36:16 vmprod sendmail[23398]: u7V7aCMr023396: to=, ctladdr= (35014/10), delay=00:00:04, xdelay=00:00:04, mailer=esmtp, pri=120534, *relay=mx-apac.mail.gm0.yahoodns.net*. [106.10.166.52], dsn=2.0.0, stat=Sent (ok dirdel) No Postfix,Exim running on this host -bash-4.1$ ps -ef | grep postifx essadmin 8974 20942 0 06:20 pts/4 00:00:00 grep postifx -bash-4.1$ ps -ef | grep exim essadmin 8982 20942 0 06:20 pts/4 00:00:00 grep exim /etc/resolv.conf is pointing to a valid DNS server . $ cat /etc/redhat-release Red Hat Enterprise Linux Server release 6.3 (Santiago) I am confused how mails are getting delivered since SMARTHOST is not configured . Any pointers ? -------------- next part -------------- An HTML attachment was scrubbed... URL: From lists at brimer.org Thu Sep 1 04:56:31 2016 From: lists at brimer.org (Barry Brimer) Date: Wed, 31 Aug 2016 23:56:31 -0500 (CDT) Subject: Sendmail Issue In-Reply-To: <946758326.2662064.1472704538546@mail.yahoo.com> References: <946758326.2662064.1472704538546.ref@mail.yahoo.com> <946758326.2662064.1472704538546@mail.yahoo.com> Message-ID: > Red Hat Enterprise Linux Server release 6.3 (Santiago) The current version of RHEL 6 is RHEL 6.8. 6.3 is several years old and some very important vulnerabilities have been fixed since then, most notably one named Shellshock. > I am confused how mails are getting delivered since SMARTHOST is not > configured . Any pointers ? A smarthost tells the mail server not to attempt to figure out how to deliver mail, i.e. look up MX records and deliver mail, but rather to blindly send all outgoing mail to a specific host known as a smarthost which will then be responsible for doing the MX lookup and delivering the mail. Think of it this way ... you have one server that is allowed to initiate connections out of your company on 25/tcp called outgoing.example.com and you have web00.example.com - web19.example.com and app00.example.com - app19.example.com. All of these 4 web and app servers need to send mail to external customers, but they can't do so directly due to firewall restrictions, so you set them all to use a smarthost (known as a relayhost in Postfix) of outgoing.example.com. Then when any of those 40 servers needs to send an email to a yahoo.com (or any other external) address, it doesn't look up the address, it blindly sends it to outgoing.example.com at which point outgoing.example.com does an MX lookup for the mail servers that handle yahoo.com email and sends the message to the Yahoo mail server with the lowest priority. Does that make sense? Hope this helps. Barry From queszama at yahoo.in Thu Sep 1 06:04:20 2016 From: queszama at yahoo.in (Zama Ques) Date: Thu, 1 Sep 2016 06:04:20 +0000 (UTC) Subject: Sendmail Issue In-Reply-To: References: <946758326.2662064.1472704538546.ref@mail.yahoo.com> <946758326.2662064.1472704538546@mail.yahoo.com> Message-ID: <858195014.2689015.1472709860905@mail.yahoo.com> Thanks Barry for your quick response.? That very much helps. I need clarification on our configuration scenario where SMARTHOST is not configured in sendmail . So , does that mean that it is querying the MX record in DNS server as configured in /etc/resolv.conf ?? The mail server in MX record is then handling the mail message to deliver it to the destination mailbox. ThanksZaman On Thursday, 1 September 2016 11:10 AM, Barry Brimer wrote: >? Red Hat Enterprise Linux Server release 6.3 (Santiago) The current version of RHEL 6 is RHEL 6.8. 6.3 is several years old and some very important vulnerabilities have been fixed since then, most notably one named Shellshock. > I am confused how mails are getting delivered since SMARTHOST is not > configured . Any pointers ? A smarthost tells the mail server not to attempt to figure out how to deliver mail, i.e. look up MX records and deliver mail, but rather to blindly send all outgoing mail to a specific host known as a smarthost which will then be responsible for doing the MX lookup and delivering the mail. Think of it this way ... you have one server that is allowed to initiate connections out of your company on 25/tcp called outgoing.example.com and you have web00.example.com - web19.example.com and app00.example.com - app19.example.com. All of these 4 web and app servers need to send mail to external customers, but they can't do so directly due to firewall restrictions, so you set them all to use a smarthost (known as a relayhost in Postfix) of outgoing.example.com. Then when any of those 40 servers needs to send an email to a yahoo.com (or any other external) address, it doesn't look up the address, it blindly sends it to outgoing.example.com at which point outgoing.example.com does an MX lookup for the mail servers that handle yahoo.com email and sends the message to the Yahoo mail server with the lowest priority. Does that make sense? Hope this helps. Barry -- redhat-sysadmin-list mailing list redhat-sysadmin-list at redhat.com https://www.redhat.com/mailman/listinfo/redhat-sysadmin-list -------------- next part -------------- An HTML attachment was scrubbed... URL: From lists at brimer.org Thu Sep 1 08:11:31 2016 From: lists at brimer.org (lists at brimer.org) Date: Thu, 1 Sep 2016 03:11:31 -0500 (CDT) Subject: Sendmail Issue In-Reply-To: <858195014.2689015.1472709860905@mail.yahoo.com> References: <946758326.2662064.1472704538546.ref@mail.yahoo.com> <946758326.2662064.1472704538546@mail.yahoo.com> <858195014.2689015.1472709860905@mail.yahoo.com> Message-ID: On Thu, 1 Sep 2016, Zama Ques wrote: > Thanks Barry for your quick response.?? That very much helps. I need > clarification on our configuration scenario where SMARTHOST is not > configured in sendmail . So , does that mean that it is querying the MX > record in DNS server as configured in /etc/resolv.conf ??? The mail > server in MX record is then handling the mail message to deliver it to > the destination mailbox. You're welcome. Yes. That is what that means. Without a SMARTHOST configured in sendmail, it will use the DNS servers in resolv.conf and query them for the MX records (if available) for the destination domains and/or hosts which you are trying to send mail to and deliver it directly to them. Barry > On Thursday, 1 September 2016 11:10 AM, Barry Brimer wrote: > > > >> ?? Red Hat Enterprise Linux Server release 6.3 (Santiago) > > The current version of RHEL 6 is RHEL 6.8. 6.3 is several years old and > some very important vulnerabilities have been fixed since then, most > notably one named Shellshock. > >> I am confused how mails are getting delivered since SMARTHOST is not >> configured . Any pointers ? > > A smarthost tells the mail server not to attempt to figure out how to > deliver mail, i.e. look up MX records and deliver mail, but rather to > blindly send all outgoing mail to a specific host known as a smarthost > which will then be responsible for doing the MX lookup and delivering the > mail. > > Think of it this way ... you have one server that is allowed to initiate > connections out of your company on 25/tcp called outgoing.example.com and > you have web00.example.com - web19.example.com and app00.example.com - > app19.example.com. All of these 4 web and app servers need to send mail to > external customers, but they can't do so directly due to firewall > restrictions, so you set them all to use a smarthost (known as a relayhost > in Postfix) of outgoing.example.com. Then when any of those 40 servers > needs to send an email to a yahoo.com (or any other external) address, it > doesn't look up the address, it blindly sends it to outgoing.example.com > at which point outgoing.example.com does an MX lookup for the mail servers > that handle yahoo.com email and sends the message to the Yahoo mail server > with the lowest priority. > > Does that make sense? > > Hope this helps. > > Barry > > -- > redhat-sysadmin-list mailing list > redhat-sysadmin-list at redhat.com > https://www.redhat.com/mailman/listinfo/redhat-sysadmin-list > > > From robert.clift at navy.mil Thu Sep 1 10:25:02 2016 From: robert.clift at navy.mil (Clift, Tom CIV NSWCDD, A24) Date: Thu, 1 Sep 2016 10:25:02 +0000 Subject: [Non-DoD Source] Sendmail Issue In-Reply-To: <946758326.2662064.1472704538546@mail.yahoo.com> References: <946758326.2662064.1472704538546.ref@mail.yahoo.com>, <946758326.2662064.1472704538546@mail.yahoo.com> Message-ID: <3A320EEF6871FF4FA313BC0DA4030FC90E921F38@NAEANRFKXM11V.nadsusea.nads.navy.mil> Check the MTA in the submit.cf and let us know what it is set to. Tom Clift 540-653-8023 DSN 249-8023 ________________________________ From: redhat-sysadmin-list-bounces at redhat.com [redhat-sysadmin-list-bounces at redhat.com] on behalf of Zama Ques [queszama at yahoo.in] Sent: Thursday, September 01, 2016 12:35 AM To: redhat-sysadmin-list at redhat.com Subject: [Non-DoD Source] Sendmail Issue Need some clarification on Mail Settings. We are managing around hundreds of applications. These applications runs on Linux based hosts and used to send mails to users based on user registration at site and other actions. We have Sendmail configured on these Linux servers to relay mails to destination mailbox. The following setting is being used in sendmail.cf to forward mails to relay mail server. DSesmtp:xmail.example.com This is fine for me. But on some servers , I can see only sendmail is running but the above settings is not enabled. But still mails are going through this server. I tried to send mails to Yahoo and GMAIL accounts and mails are successfully getting delivered. Aug 31 03:36:12 vmprod sendmail[23396]: u7V7aCMr023396: from=, size=534, class=0, nrcpts=1, msgid=<201608310736.u7V7aCee023393 at vmprod.wiley.com>, proto=ESMTP, daemon=MTA, *relay=localhost [127.0.0.1]* Aug 31 03:36:12 vmprod sendmail[23393]: u7V7aCee023393: to=queszama at yahoo.in, ctladdr=admin (35014/10), delay=00:00:00, xdelay=00:00:00, mailer=relay, pri=30220, relay=[127.0.0.1] [127.0.0.1], dsn=2.0.0, stat=Sent (u7V7aCMr023396 Message accepted for delivery) Aug 31 03:36:13 vmprod sendmail[23398]: STARTTLS=client, relay=mx-apac.mail.gm0.yahoodns.net., version=TLSv1/SSLv3, verify=FAIL, cipher=RC4-SHA, bits=128/128 Aug 31 03:36:16 vmprod sendmail[23398]: u7V7aCMr023396: to=, ctladdr= (35014/10), delay=00:00:04, xdelay=00:00:04, mailer=esmtp, pri=120534, *relay=mx-apac.mail.gm0.yahoodns.net*. [106.10.166.52], dsn=2.0.0, stat=Sent (ok dirdel) No Postfix,Exim running on this host -bash-4.1$ ps -ef | grep postifx essadmin 8974 20942 0 06:20 pts/4 00:00:00 grep postifx -bash-4.1$ ps -ef | grep exim essadmin 8982 20942 0 06:20 pts/4 00:00:00 grep exim /etc/resolv.conf is pointing to a valid DNS server . $ cat /etc/redhat-release Red Hat Enterprise Linux Server release 6.3 (Santiago) I am confused how mails are getting delivered since SMARTHOST is not configured . Any pointers ? From queszama at yahoo.in Thu Sep 1 10:49:49 2016 From: queszama at yahoo.in (Zama Ques) Date: Thu, 1 Sep 2016 10:49:49 +0000 (UTC) Subject: [Non-DoD Source] Sendmail Issue In-Reply-To: <3A320EEF6871FF4FA313BC0DA4030FC90E921F38@NAEANRFKXM11V.nadsusea.nads.navy.mil> References: <946758326.2662064.1472704538546.ref@mail.yahoo.com> <946758326.2662064.1472704538546@mail.yahoo.com> <3A320EEF6871FF4FA313BC0DA4030FC90E921F38@NAEANRFKXM11V.nadsusea.nads.navy.mil> Message-ID: <1437240069.2895416.1472726989324@mail.yahoo.com> Thanks Clift? . Please find MTA value in submit.cf -bash-4.1$ grep -i mta /etc/mail/submit.cf #D{sendmailMTACluster}$m D{MTAHost}[127.0.0.1] ThanksZaman On Thursday, 1 September 2016 3:55 PM, "Clift, Tom CIV NSWCDD, A24" wrote: Check the MTA in the submit.cf and let us know what it is set to. Tom Clift 540-653-8023 DSN? 249-8023 ________________________________ From: redhat-sysadmin-list-bounces at redhat.com [redhat-sysadmin-list-bounces at redhat.com] on behalf of Zama Ques [queszama at yahoo.in] Sent: Thursday, September 01, 2016 12:35 AM To: redhat-sysadmin-list at redhat.com Subject: [Non-DoD Source] Sendmail Issue Need some clarification on Mail Settings. We are managing around hundreds of applications. These applications runs on Linux based hosts and used to send mails to users based on user registration at site and other actions. We have Sendmail configured on these Linux servers to relay mails to destination mailbox. The following setting is being used in sendmail.cf to forward mails to relay mail server. ? ? ? ? DSesmtp:xmail.example.com This is fine for me. But on some servers , I can see only sendmail is running but the above settings is not enabled. But still mails are going through this server. I tried to send mails to Yahoo and GMAIL accounts and mails are successfully getting delivered. ? Aug 31 03:36:12 vmprod sendmail[23396]: u7V7aCMr023396: from=, size=534, class=0, nrcpts=1, msgid=<201608310736.u7V7aCee023393 at vmprod.wiley.com>, proto=ESMTP, daemon=MTA, *relay=localhost [127.0.0.1]* ? Aug 31 03:36:12 vmprod sendmail[23393]: u7V7aCee023393: to=queszama at yahoo.in, ctladdr=admin (35014/10), delay=00:00:00, xdelay=00:00:00, mailer=relay, pri=30220, relay=[127.0.0.1] [127.0.0.1], dsn=2.0.0, stat=Sent (u7V7aCMr023396 Message accepted for delivery) ? Aug 31 03:36:13 vmprod sendmail[23398]: STARTTLS=client, relay=mx-apac.mail.gm0.yahoodns.net., version=TLSv1/SSLv3, verify=FAIL, cipher=RC4-SHA, bits=128/128 ? Aug 31 03:36:16 vmprod sendmail[23398]: u7V7aCMr023396: to=, ctladdr= (35014/10), delay=00:00:04, xdelay=00:00:04, mailer=esmtp, pri=120534, *relay=mx-apac.mail.gm0.yahoodns.net*. [106.10.166.52], dsn=2.0.0, stat=Sent (ok dirdel) No Postfix,Exim running on this host ? -bash-4.1$ ps -ef | grep postifx ? essadmin? 8974 20942? 0 06:20 pts/4? ? 00:00:00 grep postifx ? -bash-4.1$ ps -ef | grep exim ? essadmin? 8982 20942? 0 06:20 pts/4? ? 00:00:00 grep exim /etc/resolv.conf is pointing to a valid DNS server . ? $ cat /etc/redhat-release ? Red Hat Enterprise Linux Server release 6.3 (Santiago) I am confused how mails are getting delivered since SMARTHOST is not configured . Any pointers ? -------------- next part -------------- An HTML attachment was scrubbed... URL: From queszama at yahoo.in Mon Sep 5 07:07:06 2016 From: queszama at yahoo.in (Zama Ques) Date: Mon, 5 Sep 2016 07:07:06 +0000 (UTC) Subject: [Non-DoD Source] Sendmail Issue In-Reply-To: <1437240069.2895416.1472726989324@mail.yahoo.com> References: <946758326.2662064.1472704538546.ref@mail.yahoo.com> <946758326.2662064.1472704538546@mail.yahoo.com> <3A320EEF6871FF4FA313BC0DA4030FC90E921F38@NAEANRFKXM11V.nadsusea.nads.navy.mil> <1437240069.2895416.1472726989324@mail.yahoo.com> Message-ID: <348229458.1215753.1473059226354@mail.yahoo.com> Hi All , Can anybody please provide some clue regarding this mail issue? based on the information I provided. ThanksZaman On Thursday, 1 September 2016 4:19 PM, Zama Ques wrote: Thanks Clift? . Please find MTA value in submit.cf -bash-4.1$ grep -i mta /etc/mail/submit.cf #D{sendmailMTACluster}$m D{MTAHost}[127.0.0.1] ThanksZaman On Thursday, 1 September 2016 3:55 PM, "Clift, Tom CIV NSWCDD, A24" wrote: Check the MTA in the submit.cf and let us know what it is set to. Tom Clift 540-653-8023 DSN? 249-8023 ________________________________ From: redhat-sysadmin-list-bounces at redhat.com [redhat-sysadmin-list-bounces at redhat.com] on behalf of Zama Ques [queszama at yahoo.in] Sent: Thursday, September 01, 2016 12:35 AM To: redhat-sysadmin-list at redhat.com Subject: [Non-DoD Source] Sendmail Issue Need some clarification on Mail Settings. We are managing around hundreds of applications. These applications runs on Linux based hosts and used to send mails to users based on user registration at site and other actions. We have Sendmail configured on these Linux servers to relay mails to destination mailbox. The following setting is being used in sendmail.cf to forward mails to relay mail server. ? ? ? ? DSesmtp:xmail.example.com This is fine for me. But on some servers , I can see only sendmail is running but the above settings is not enabled. But still mails are going through this server. I tried to send mails to Yahoo and GMAIL accounts and mails are successfully getting delivered. ? Aug 31 03:36:12 vmprod sendmail[23396]: u7V7aCMr023396: from=, size=534, class=0, nrcpts=1, msgid=<201608310736.u7V7aCee023393 at vmprod.wiley.com>, proto=ESMTP, daemon=MTA, *relay=localhost [127.0.0.1]* ? Aug 31 03:36:12 vmprod sendmail[23393]: u7V7aCee023393: to=queszama at yahoo.in, ctladdr=admin (35014/10), delay=00:00:00, xdelay=00:00:00, mailer=relay, pri=30220, relay=[127.0.0.1] [127.0.0.1], dsn=2.0.0, stat=Sent (u7V7aCMr023396 Message accepted for delivery) ? Aug 31 03:36:13 vmprod sendmail[23398]: STARTTLS=client, relay=mx-apac.mail.gm0.yahoodns.net., version=TLSv1/SSLv3, verify=FAIL, cipher=RC4-SHA, bits=128/128 ? Aug 31 03:36:16 vmprod sendmail[23398]: u7V7aCMr023396: to=, ctladdr= (35014/10), delay=00:00:04, xdelay=00:00:04, mailer=esmtp, pri=120534, *relay=mx-apac.mail.gm0.yahoodns.net*. [106.10.166.52], dsn=2.0.0, stat=Sent (ok dirdel) No Postfix,Exim running on this host ? -bash-4.1$ ps -ef | grep postifx ? essadmin? 8974 20942? 0 06:20 pts/4? ? 00:00:00 grep postifx ? -bash-4.1$ ps -ef | grep exim ? essadmin? 8982 20942? 0 06:20 pts/4? ? 00:00:00 grep exim /etc/resolv.conf is pointing to a valid DNS server . ? $ cat /etc/redhat-release ? Red Hat Enterprise Linux Server release 6.3 (Santiago) I am confused how mails are getting delivered since SMARTHOST is not configured . Any pointers ? -------------- next part -------------- An HTML attachment was scrubbed... URL: