summaryrefslogtreecommitdiffstats
path: root/html/LINUX_README.html
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--html/LINUX_README.html119
1 files changed, 119 insertions, 0 deletions
diff --git a/html/LINUX_README.html b/html/LINUX_README.html
new file mode 100644
index 0000000..0d5b0ee
--- /dev/null
+++ b/html/LINUX_README.html
@@ -0,0 +1,119 @@
+<!doctype html public "-//W3C//DTD HTML 4.01 Transitional//EN"
+ "http://www.w3.org/TR/html4/loose.dtd">
+
+<html>
+
+<head>
+
+<title>Postfix and Linux</title>
+
+<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
+
+</head>
+
+<body>
+
+<h1><img src="postfix-logo.jpg" width="203" height="98" ALT="">Postfix and Linux</h1>
+
+<hr>
+
+<h2> Host lookup issues </h2>
+
+<p> By default Linux /etc/hosts lookups do not support multiple IP
+addresses per hostname. This causes warnings from the Postfix SMTP
+server that "hostname XXX does not resolve to address YYY", and is
+especially a problem with hosts that have both IPv4 and IPv6
+addresses. To fix this, turn on support for multiple IP addresses: </p>
+
+<blockquote>
+<pre>
+/etc/host.conf:
+ ...
+ # We have machines with multiple IP addresses.
+ multi on
+ ...
+</pre>
+</blockquote>
+
+<p> Alternatively, specify the RESOLV_MULTI environment variable
+in <a href="postconf.5.html">main.cf</a>: </p>
+
+<blockquote>
+<pre>
+/etc/postfix/<a href="postconf.5.html">main.cf</a>:
+ <a href="postconf.5.html#import_environment">import_environment</a> = MAIL_CONFIG MAIL_DEBUG MAIL_LOGTAG TZ XAUTHORITY DISPLAY LANG=C RESOLV_MULTI=on
+</pre>
+</blockquote>
+
+<h2>Berkeley DB issues</h2>
+
+<p> If you can't compile Postfix because the file "db.h"
+isn't found, then you MUST install the Berkeley DB development
+package (name: db???-devel-???) that matches your system library.
+You can find out what is installed with the rpm command. For example:
+</p>
+
+<blockquote>
+<pre>
+$ <b>rpm -qf /usr/lib/libdb.so</b>
+db4-4.3.29-2
+</pre>
+</blockquote>
+
+<p> This means that you need to install db4-devel-4.3.29-2 (on
+some systems, specify "<b>rpm -qf /lib/libdb.so</b>" instead). </p>
+
+<p> DO NOT download some Berkeley DB version from the network.
+Every Postfix program will dump core when it is built with a different
+Berkeley DB version than the version that is used by the system
+library routines. See the <a href="DB_README.html">DB_README</a> file for further information.
+</p>
+
+<h2>Procmail issues</h2>
+
+<p> On RedHat Linux 7.1 and later <b>procmail</b> no longer has
+permission
+to write to the mail spool directory. Workaround: </p>
+
+<blockquote>
+<pre>
+# chmod 1777 /var/spool/mail
+</pre>
+</blockquote>
+
+<h2>Logging in a container</h2>
+
+<p> When running Postfix inside a container, you can use stdout
+logging as described in <a href="MAILLOG_README.html">MAILLOG_README</a>. Alternatives: run syslogd
+inside the container, or mount the host's syslog socket inside the
+container. </p>
+
+<h2>Syslogd performance</h2>
+
+<p> LINUX <b>syslogd</b> uses synchronous writes by default. Because
+of this, <b>syslogd</b> can actually use more system resources than
+Postfix. To avoid such badness, disable synchronous mail logfile
+writes by editing /etc/syslog.conf and by prepending a - to the
+logfile name: </p>
+
+<blockquote>
+<pre>
+/etc/syslog.conf:
+ mail.* -/var/log/mail.log
+</pre>
+</blockquote>
+
+<p> Send a "<b>kill -HUP</b>" to the <b>syslogd</b> to make the
+change effective. </p>
+
+<h2>Other logging performance issues</h2>
+
+<p> LINUX <b>systemd</b> intercepts all logging and enforces its
+own rate limits before handing off requests to a backend such as
+<b>rsyslogd</b> or <b>syslog-ng</b>. On a busy mail server this can
+result in information loss. As a workaround, you can use Postfix's
+built-in logging as described in <a href="MAILLOG_README.html">MAILLOG_README</a>. </p>
+
+</body>
+
+</html>