There are many places (see the Linux MAIL HOWTO in comp.answers or on rtfm.mit.edu for a list), but the definitive place is in the sendmail+IDA sources. Look in the directory <IDA_SRC_PATH>/ida/cf for the files DBM-GUIDE, OPTIONS, and Sendmail.mc.
Thanks go to Neil Rickert and Paul Pomes for lots of help over the years regarding the care and feeding of sendmail+IDA and to Rich Braun for doing the initial port of sendmail+IDA to Linux.
There is no “true standard configuration” of electronic mail transport and delivery agents and there is no “one true directory structure”.
Accordingly, it is necessary to ensure that all the various pieces of the system (Usenet news, mail, tcp/ip) agree on the location of the local mail delivery program (lmail, deliver, etc.), remote mail delivery program (rmail), and the mail transport program (sendmail or smail). Such assumptions are not generally documented, although use of the 'strings' command can help determine what files and directories are expected. The following are some problems we've seen in the past with some of the commonly available Linux binary distributions and sources.
Some versions of the NET-2 distribution of tcp/ip have services defined for a program called 'umail' rather than sendmail.
There are various ports of Elm and mailx that look for a delivery agent of /usr/bin/smail rather than sendmail.
Sendmail+IDA has a built-in local mailer for 'deliver', but expects it to be located in /bin rather than the more typical Linux location of /usr/bin.
Rather than go to the trouble of building all the mail clients from sources, we generally fake it with the appropriate soft links...
You set the default smart host via the RELAY_HOST and RELAY_MAILER parameters in the sendmail.m4 file that is processed into sendmail.cf.
To forward mail to a particular host or domain to a designated relay system, generally use the mailertable.
For example, to forward mail for relayhost.com to their uucp gateway system 'uucpgate'.
(in mailertable)UUCP-A,uucpgate relayhost.com
Frequently, Internet hosts will have trouble getting mail into misconfigured remote sites. There are several variants of this problem, but the general symptom is that mail is bounced by the remote system or never gets there at all.
These problems can put the local system administrator in a bad position because your users generally don't care that you don't personally administer every system worldwide (or know how to get the remote administrator to fix the problem). They just know that their mail didn't get through to the desired recipient on the other end and that you're a likely person to compain to.
A remote site's configuration is their problem, not yours. In all cases, be certain to NOT break your site in order to communicate with a misconfigured remote site. If you can't get in touch with the Postmaster at the remote site to get them to fix their configuration in a timely manner, you have two options.
It is generally possible to force mail into the remote system successfully, although since the remote system is misconfigured, replies on the remote end might not work...but then that's the remote administrator's problem.
You can fix the bad headers in the envelope on your outgoing messages only by putting a domaintable entry for their host/domain that results in the invalid information being corrected in mail originating from your site:
# (in domaintable) braindead_site.correct.domain.com braindead_site.wrong.domain.com
Treat them as totally brain-dead and strip off all hostname.domain information in the envelope of messages to them from your site.
The '!' in the following results in mail being delivered to their remote site and appearing to be locally originated (for sendmail purposes). The return address for your site will not be changed, so the proper return address will still show up in the message.
# (in mailertable) TCP!braindead_site.correct.domain.com braindead_site.wrong.domain.com
Regardless, even if you get mail into their system, there is no guarantee that they can reply to your message (they're broken, remember...) but then their users are yelling at their administrators rather than your users yelling at you.
Free Webinar: Hadoop
How to Build an Optimal Hadoop Cluster to Store and Maintain Unlimited Amounts of Data Using Microservers
Realizing the promise of Apache® Hadoop® requires the effective deployment of compute, memory, storage and networking to achieve optimal results. With its flexibility and multitude of options, it is easy to over or under provision the server infrastructure, resulting in poor performance and high TCO. Join us for an in depth, technical discussion with industry experts from leading Hadoop and server companies who will provide insights into the key considerations for designing and deploying an optimal Hadoop cluster.
Some of key questions to be discussed are:
- What is the “typical” Hadoop cluster and what should be installed on the different machine types?
- Why should you consider the typical workload patterns when making your hardware decisions?
- Are all microservers created equal for Hadoop deployments?
- How do I plan for expansion if I require more compute, memory, storage or networking?
|Dynamic DNS—an Object Lesson in Problem Solving||May 21, 2013|
|Using Salt Stack and Vagrant for Drupal Development||May 20, 2013|
|Making Linux and Android Get Along (It's Not as Hard as It Sounds)||May 16, 2013|
|Drupal Is a Framework: Why Everyone Needs to Understand This||May 15, 2013|
|Home, My Backup Data Center||May 13, 2013|
|Non-Linux FOSS: Seashore||May 10, 2013|
- RSS Feeds
- Making Linux and Android Get Along (It's Not as Hard as It Sounds)
- Using Salt Stack and Vagrant for Drupal Development
- Dynamic DNS—an Object Lesson in Problem Solving
- New Products
- Validate an E-Mail Address with PHP, the Right Way
- Drupal Is a Framework: Why Everyone Needs to Understand This
- A Topic for Discussion - Open Source Feature-Richness?
- Download the Free Red Hat White Paper "Using an Open Source Framework to Catch the Bad Guy"
- Tech Tip: Really Simple HTTP Server with Python
- Roll your own dynamic dns
4 hours 47 min ago
- Please correct the URL for Salt Stack's web site
7 hours 58 min ago
- Android is Linux -- why no better inter-operation
10 hours 13 min ago
- Connecting Android device to desktop Linux via USB
10 hours 42 min ago
- Find new cell phone and tablet pc
11 hours 40 min ago
13 hours 9 min ago
- Automatically updating Guest Additions
14 hours 17 min ago
- I like your topic on android
15 hours 4 min ago
- This is the easiest tutorial
21 hours 39 min ago
- Ahh, the Koolaid.
1 day 3 hours ago