<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<meta name="Generator" content="Microsoft Word 14 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri","sans-serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
p.MsoListParagraph, li.MsoListParagraph, div.MsoListParagraph
{mso-style-priority:34;
margin-top:0in;
margin-right:0in;
margin-bottom:0in;
margin-left:.5in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri","sans-serif";}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:"Calibri","sans-serif";
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri","sans-serif";}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
/* List Definitions */
@list l0
{mso-list-id:466315489;
mso-list-type:hybrid;
mso-list-template-ids:1819171174 67698705 67698713 67698715 67698703 67698713 67698715 67698703 67698713 67698715;}
@list l0:level1
{mso-level-text:"%1\)";
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level2
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level3
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
@list l0:level4
{mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level5
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level6
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
@list l0:level7
{mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level8
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level9
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
@list l1
{mso-list-id:1928078605;
mso-list-type:hybrid;
mso-list-template-ids:-1300064390 67698705 67698713 67698715 67698703 67698713 67698715 67698703 67698713 67698715;}
@list l1:level1
{mso-level-text:"%1\)";
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l1:level2
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l1:level3
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
@list l1:level4
{mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l1:level5
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l1:level6
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
@list l1:level7
{mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l1:level8
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l1:level9
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
ol
{margin-bottom:0in;}
ul
{margin-bottom:0in;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang="EN-US" link="blue" vlink="purple">
<div class="WordSection1">
<p class="MsoNormal">Note this is not a question about the normal “your SMS messages may be delayed or isn’t guaranteed” if you’re not using their SMS for business service. This is a question that appears to be unique to the way AT&T is handling our text
messages from Linux vs. the way other carriers such as Verizon and T-Mobile do.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo2"><![if !supportLists]><span style="mso-list:Ignore">1)<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]> Is there a way to configure Sendmail so that mail it relays to other hosts use the short name of the Linux server where it originated?<br>
<br>
<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo2"><![if !supportLists]><span style="mso-list:Ignore">2)<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Alternatively, does anyone know if AT&T is delaying email because it does a hostname lookup for sender email when going to @txt.att.net. (i.e. Iis there any benefit in making a *.<ourdomain>.com DNS record so any of <hostname>.<ourdomain>.com
hosts resolve an IP to solve the issue at AT&T?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">DETAILS:<o:p></o:p></p>
<p class="MsoNormal">We got a complaint today that email from one of our servers to going to AT&T Mobile phone is being delayed when it comes from one of our Linux servers but not when it is sent via Outlook/Exchange directly.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The sending server is using RHEL5.10 and Sendmail. It relays through a MS Exchange server here for all mail.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The mail is sent to <phonenumber>@txt.att.net when we need to send a text from our application.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">My findings:<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l1 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">1)<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]> The mail sent to @txt.att.net per /var/log/maillog is being sent as soon as the command is run.<o:p></o:p></p>
<p class="MsoListParagraph"><o:p> </o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l1 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">2)<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]> The relaying Exchange server is accepting the mail and is sending it to txt.att.net almost immediately.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l1 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">3)<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]> Mail going to Verizon (@vtext.com) and T-Mobile (@tmomail.net) using same command line on Linux is appearing on the phones almost immediately.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l1 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">4)<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Sender in relayed emails is <a href="mailto:root@%3cserver%3e.%3courdomain%3e.com">
root@<server>.<ourdomain>.com</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l1 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">5)<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Issue occurs if I do telnet to port 25 of the Exchange server from the Linux server. (i.e. Do direct smtp and bypass Linux Sendmail config).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l1 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">6)<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Test from Outlook confirms that the email goes to the AT&T phone text message almost immediately.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l1 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">7)<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>We found a Windows server running an application that does smtp to the Exchange server on port 25. When it sends messages to @txt.att.net they are received on the phone almost immediately. That message was also sent to a real mailbox
and review of headers there show it took the sending server’s shortname rather than FQDN.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l1 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">8)<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Based on findings from 8 I redid the test from 5 using the shortname of the Linux server rather than the FQDN it usually sends (which I’d used in test 5) and this also went to the phone almost immediately.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><i><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">Jeffrey C. Lightner</span></i><i><span style="font-size:12.0pt"><o:p></o:p></span></i></p>
<p class="MsoNormal"><i><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">Sr. UNIX/Linux Administrator</span></i><i><o:p></o:p></i></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""> <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">DS Services of America, Inc.</span><span style="font-size:12.0pt;font-family:"Times New Roman","serif""><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">2300 Windy Ridge Pkwy</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">Suite
<i>600 N</i></span><span style="font-family:"Times New Roman","serif""><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="PT" style="font-size:10.0pt;font-family:"Arial","sans-serif"">Atlanta, GA 30339-8461</span><span lang="PT"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="PT" style="font-size:10.0pt;font-family:"Arial","sans-serif""> <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="PT" style="font-size:10.0pt;font-family:"Arial","sans-serif"">P:
<i>678-486-3516<o:p></o:p></i></span></p>
<p class="MsoNormal"><span lang="PT" style="font-size:10.0pt;font-family:"Arial","sans-serif"">C:
<i>678-772-0018</i></span><span lang="PT" style="font-size:12.0pt;font-family:"Times New Roman","serif""><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="PT" style="font-size:10.0pt;font-family:"Arial","sans-serif"">F:
<i>678-460-3603</i></span><span lang="PT"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="PT" style="font-size:10.0pt;font-family:"Arial","sans-serif"">E:
<i>jlightner@dsservices.com</i><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<p style="font-size:10pt; line-height:10pt; font-family: 'Arial','times roman',serif;">
CONFIDENTIALITY NOTICE: This e-mail may contain privileged or confidential information and is for the sole use of the intended recipient(s). If you are not the intended recipient, any disclosure, copying, distribution, or use of the contents of this information
is prohibited and may be unlawful. If you have received this electronic transmission in error, please reply immediately to the sender that you have received the message in error, and delete it. Thank you
</p>
<span style="padding-top:10px; font-weight:color:#CC0000; font-size:10pt; font-family: 'Arial',Arial,sans-serif; ">
<p></p>
</span><br>
<br>
<div></div>
</body>
</html>