LinuxHostingSupport

The Postfix mail logs may indicate the following error when emails are not working:

postdrop: warning: unable to look up public/pickup: No such file or directory

It turns out to be sendmail running along with Postfix and creating issues. The fix is to stop/remove sendmail and create the necessary postfix directory and restart the postfix service.

# /etc/init.d/sendmail stop

#  mkfifo /var/spool/postfix/public/pickup

# /etc/init.d/postfix restart

The alternative / equivalent of chkconfig in Ubuntu is “sysv-rc-conf”. To install sysv-rc-conf, ssh to the server and execute:

# apt-get install sysv-rc-conf

to start manging the services, execute

# sysv-rc-conf

It’s an easy to use interface for managing /etc/rc{runlevel}.d/ symlinks.  sysv-rc-conf provides a graphical view for turning services on and off at startup.

The steps to install the PHP ‘Fileinfo’ module on a Linux server is as below:

1) Download and untar the package

# wget http://pecl.php.net/get/Fileinfo-1.0.4.tgz
# tar -zxf Fileinfo-1.0.4.tgz
# cd Fileinfo-1.0.4

2) Generate the extension for compiling

# phpize

3) Configure the module

# ./configure

4) generate the install files and install it

# make
# make install

5) Once done, the extension will be available under the /usr/lib64/php/modules directory.
You now need to add the extension somewhere in the php configuration file. Edit /etc/php.ini and add the following:

extension=fileinfo.so

6) Save the file and restart the webserver

# service httpd restart

To check if “fileinfo” is enabled on the server, execute:

# php -i | grep fileinfo
fileinfo
fileinfo support => enabled

Alternate method

Just an FYI, the module can also be installed using the PECL command i.e.

# pecl install fileinfo

Once done, just follow steps 5 and 6 mentioned above. That’s it.

While accessing an email using Horde, you may notice that Horde isn’t displaying the contents of the email rather it displays the following message

"there are no parts that can be displayed inline."

The reason is the “inline” setting of the HTML driver is set to false. To fix the issue, you need to enable i.e. change false to true for  “imp/html/inline” attribute in the Horde’s mime_drivers.php file.

On a cPanel server, the file is located at /usr/local/cpanel/base/horde/imp/config/mime_drivers.php and the attribue it as:

$mime_drivers['imp']['html'] = array(
 'inline' => false;

On a Plesk server, the file is located at /etc/psa-horde/imp/mime_drivers.php and the attribute is as:

$mime_drivers['imp']['html']['inline'] = false;

Once you change the attribute to ‘true’, save the file and Horde will start displaying the contents of the email.

Recently I had a problem while sending emails to a specific server and while looking at the logs I saw the following:

451-The server has reached its limit for processing requests from your host.
\n451 Please try again later.
T=remote_smtp defer (-53): retry time not reached for any host

The reason could either be the exim rate limiting the number of emails OR the exim databases are corrupted. In such a case, you have 2 options

1) Increase the number of emails each domain can send per hour from WHM >> Tweak Settings >> Max hourly emails.

2) If step 1 does not help, its clearly a case of exim database corruption, and to resolve the issue using the exim database tool called “exim_tidydb”. SSH to your server and execute:

# /usr/sbin/exim_tidydb -t 1d /var/spool/exim retry > /dev/null
# /usr/sbin/exim_tidydb -t 1d /var/spool/exim reject > /dev/null
# /usr/sbin/exim_tidydb -t 1d /var/spool/exim wait-remote_smtp > /dev/null

Once done, reinstall courier and exim using the cPanel scripts.

# /scripts/courierup -- force
# /scripts/eximup --force

You should now be able to send emails from the server.