Issue :

How can emails going out from a particular domain be copied to a common email address ?

Solution :

In order to set up a forwarder for outgoing emails from a particular domain to another email address, use the following steps :

First, open the file /etc/cpanel_exim_system_filter using any of your favorite editors.

Add the following content to it :

if (
$received_protocol is “local” or
$received_protocol is “esmtpa” or
$received_protocol is “smtp”
) and (
$header_from contains “@domainname.com” )
then
unseen deliver username@domainname.com
endif

Now, if you DO NOT want to forward outgoing emails from a particular email address on that domain, you can add the following code in the /etc/cpanel_exim_system_filter file :

if (
$received_protocol is “local” or
$received_protocol is “esmtpa” or
$received_protocol is “smtp”
) and (
$sender_address is not ” username_escape@domainname.com
and (
$header_from contains “@domainname.com” )
then
unseen deliver username@domainname.com
endif

Finally, you should replace the values of the variables used in the above codes.

domainname.com – the actual domain
username@domainname.com – email address to which you want to forward.
username_escape@domainname.com – email address that you don’t want to forward

Save and exit the file.

Restart Exim using any of the the following commands :

/scripts/restartsrv_exim or

/etc/init.d/exim restart or

service exim restart

Issue :

It seems that by default, it is set to reject mails with a spam score of more than 20 at SMTP time. How to change the value of spam score for rejecting the mails at SMTP time ?

Solution :

You can do that by doing the following :

1. Go to WHM >> Main >> Service Configuration >> Exim Configuration Editor
2. Look for the section ‘ACL Options’ .
3. The first parameter under that deals with the spam score setting at SMTP time. De-select the check box corresponding to that.
4. When you de-select the check box, it will give you the other available options. Check the box corresponding to the desired value.
5. Click on ‘Save’ at the bottom to save the settings.

Issue :

How to block emails from a specific address on a cPanel/WHM server using Exim ?

Solution :

This is fairly easy to achieve with Exim.
First you’ll need to find the system filter file for Exim. This can be found out through WHM >> Main >> Service Configuration >> Exim Configuration Editor.
Towards the middle of the page, under the section ‘Filters’ , you ‘ll find the path to the file.
Open that file via SSH using your favorite editor and add the following to it :

if first_delivery
and ( (“$h_from:” contains “emailtoblock@domainname.com”)
)
then fail
endif

If you would like a copy of the email to be sent to you after the message fails, use the following code :

if first_delivery
and ( (“$h_from:” contains “emailtoblock@domainname.com”)
)
then
unseen deliver “youremail@yourdomainname.com”
fail
endif

Make sure that you substitute the correct email addresses in the above code.

Issue :

How can the overall size of an email including attachment, encoding etc. be limited to a pre-defined value?

Solution :

This can be done in the following way :
Go to WHM >> Main >> Service Configuration >> Exim Configuration Editor
In the first box where you can type ( right below where you see ‘#!!# cPanel Exim 4 Config’ ), add the following directive :

message_size_limit = 100M

This will limit the overall size of the message to 100Mb

We can achieve this by starting exim on the particular port (say 588) using the following command:

/usr/sbin/exim -oX 588 -bd

But to get this done automatically whenever exim starts, do the following:

1) In /etc/chkserv.d, add a file called exim_588 (to run it on port 588).

Note the underscore there. Do not replace it with hyphen as there is another file exim-26 that uses that. The content of the file would be:

service[exim-588]=588,QUIT,220,/etc/rc.d/init.d/exim stop;/etc/rc.d/init.d/exim stop;/etc/rc.d/init.d/exim stop;/etc/rc.d/init.d/exim start;/usr/sbin/exim -oX 588 -bd

2) Enable it in /etc/chkserv.d/chkservd.conf

exim_588:1

3) Now make the following changes in /etc/init.d/exim. Search for ALTPORT and add the following lines below that:

if [ "`echo $file | awk -F_ '{ print $1 }'`" = "exim" ]; then
ALTPORT2=”`echo $file | awk -F_ ‘{ print $2 }’`”
fi

Again search for it and add these lines:

if [ "$ALTPORT2" != "" -a "`grep \"daemon_smtp_port.* $ALTPORT2\" /etc/exim.conf`" = "" ]; then
echo -n “Starting exim-$ALTPORT2: ”
TMPDIR=/tmp $DAEMONIZE /usr/sbin/exim -bd -oX $ALTPORT2
echo $RESULT
fi

This will ensure that exim runs on port 588 on start. You can also see it enabled in Whm >> Service Manager.

Issue :

Port 25 blocked is blocked by ISPs. How to add an alternate port ?

Fix :

Assuming that you want to use , say , port 666.
Put the following line in the first text box in Advanced Exim Editor :

daemon_smtp_ports = 25 : 666

OR

Go to WHM >> Service Configuration >> Service Manager and check the check-box for “exim on another port.”

Removing Bad Mail

for i in `exiqgrep -i -f nobody`; do exim -Mrm $i; done >> Removes Nobody Mail

for i in `exiqgrep -i -o 259200`; do exim -Mrm $i; done >> Removes Mail older than 3 Days

for i in `exiqgrep -i -f “^<>$”`; do exim -Mrm $i; done >> Removes Mail with weird Characters (Spam)

Delete mails from a particular domain

for i in `exiqgrep -i -f domain.com`; do exim -Mrm $i; done

Delete mails to a particular domain

for i in `exiqgrep -i -r domain.com`; do exim -Mrm $i; done

Flush the entire Mail queue

for i in `exiqgrep -i -f `; do exim -Mrm $i; done

Run Mail queue

runq -qqff&

Who is having large number of emails?

exim -bp | exiqsumm

To check message header

exim -Mvh messageid

To check message content

exim -Mvb messageid

Here is a small but handy script which will clear the queued emails from the server.

exim -bpc
exim -bpru | grep frozen | awk {‘print $3′}|xargs exim -Mrm
exim -bpru | grep “<>” | awk {‘print $3′}|xargs exim -Mrm
exim -bpru | grep “nobody” | awk {‘print $3′}|xargs exim -Mrm
exim -bpru|awk {‘print $3′}|xargs exim -Mrm
exiqgrep -o 86400 -i | xargs exim -Mrm
exim -bpc

This script will display the number of queued emails before clearing, then clear them and display the number after clearing them.

Running out of disk space is a very common issue.  Be it a web-hosting service provider or the end-user.  I wanted to share a few tips that the technical support staff  at InstaCarma use to resolve disk-space issues on a cPanel server. As we all know, there are various partitions on a server which are meant for different purposes. So, the methods used to deal with space issues on these partitions will also vary. Let us see them one by one.

The /USR partition

1. Restart the httpd service. This might free a little space some times.

2. Check for apache logs like error_log, access_log , suexec_log in /usr/local/apache/logs . These can either be cleared off or if you need the logs then you can take a zipped copy and keep it aside.

3. Same can be done for the files in cPanel logs (/usr/local/cpanel/logs)  as well .

4. Domlogs – Get into  the /usr/local/apache/domlogs/ directory. Run the following command :-

# ls -al -SR | head -10        —> It will list 10 files in the decreasing order according to their size

If the domlog file is too large for a domain then it is possible that awstats is not running . Check whether cpanellogd is running on the server  using  pstree . If not, restart it .
Else, it is possible that awstats for only that particular domain is not updating. Get into the directory /usr/local/cpanel/base and check if any file as ‘awstats.domainname.com.conf’ exists.   If yes , delete that file.

Now,  run /scripts/runweblogs for that user.  It will update the awstats and automatically clear the domlogs file thereafter. Do not delete the domlogs file itself.

5. Remove old and unwanted backups of  ‘apache’  that might have been taken long ago. Also, check for any other duplicate folders that can be removed safely.

6. Remove core files, if any . Normally, some core files (like core.1234) might be present in /usr/local/cpanel/whostmgr/docroot . Check for these and remove them.

—————————————————–

The /HOME partition

1.  Check for unwanted cpmove/tar files for the user accounts in /home and delete them.

2.  Check for any cpmove folders as well in /home

3.  Check the folder ‘cprestore’  in /home for any tar files. Be careful. These should  be deleted only if they are very old,say about 4-5 months.

4. Using find command you can check for unwanted tar files(especially cpmove/backup) in the entire home directory. Check their size. If you think that deleting them will  make considerable difference to the disk space then delete them.

5. Check for core files and delete them.

6.  Search for large accounts and see if they are hosting any prohibited content or violating your company policies. If yes, take appropriate measures as per your policies.

—————————————————–

The /VAR partition

1. Restart the mysql service.

2. Log files in /var/log like exim_mainlog, mailmon.log, messages, mysqld.log, mysql_slow_queries.log  can be deleted after taking backups of the required ones..

Note that there is no point in deleting these log files if the size is very small. Check whether deleting these would make any difference.

If you are deleting them then do re-create the files, or you can use the command ‘echo ” ” > logfile’ to empty the existing files.

3.  Clear Mysql logs like server-name.err or any other  present  in /var/lib/mysql

4. Delete mysql-bin.000* file  in /var/lib/mysql, if present.

5. There might be useless large .sql files   in /var/lib/mysql . Delete them.

6.  Remove unwanted emails from spool. You can use the following code to do that :

exim -bpc
exim -bpru | grep frozen | awk {‘print $3′}|xargs exim -Mrm
exim -bpru | grep “<>” | awk {‘print $3′}|xargs exim -Mrm
exim -bpru | grep “nobody” | awk {‘print $3′}|xargs exim -Mrm
exim -bpru|awk {‘print $3′}|xargs exim -Mrm
exiqgrep -o 86400 -i | xargs exim -Mrm
exim -bpc

7. There might be yum cache files inside the /var/cache folder which can take space. To remove them do:
#  yum clear all
#  yum list all

8. Again, search for any core files ( core dump ) like core.12* etc.

—————————————————–

The /BACKUP partition

1. Remove any tar/cpmove files if they are too old and large.

2. Remove any old  configuration backups ( like apache.bkp) or any log file backup , say 3-4 months old.

3. Check for core files and remove them.

These are some of the general steps that can be followed to deal with space issues on the servers.

Issue :

Sometimes when trying to send emails , the following error shows up :

“550 postmaster verification failed”

This is one way of verifying that the sending server is in fact the real sender and not relaying and also the email is being sent by a genuine source.

Fix :

Create a mailbox named postmaster@senderdomain.tld on the domain which is sending emails.
This should fix it.

Some mail server admins are now implementing this. If someone has any other suggestion on this then do post it here.

If you have IP addresses which should always be able to relay mail without having to authenticate first ,all you have to do is:

create the file /etc/alwaysrelay and add the IP addresses .

For example:

vi  /etc/alwaysrelay

Add the IPs,

192.168.0.1
10.10.10.98

Then, restart exim (/etc/init.d/exim restart or ‘service exim restart’)

After this either restart antirelayd or wait for a little while and it will automatically include these IPs in /etc/relayhosts

Issue :

Sometimes you may find that you are unable to send mails and will find the following lines in your exim mainlog:
2009-04-05 19:08:41 H=[xx.xx.xx.xx] temporarily rejected connection in ?connect? ACL: ratelimit database not available

Cause :

The exim cache database might be corrupted.

Fix :

You need to delete the following files :
/var/spool/exim/db/ratelimit?
/var/spool/exim/db/ratelimit.lockfile?
/var/spool/exim/db/retry?
/var/spool/exim/db/retry.lockfile?
/var/spool/exim/db/wait-dk_remote_smtp?
/var/spool/exim/db/wait-dk_remote_smtp.lockfile?
/var/spool/exim/db/wait-remote_smtp?
/var/spool/exim/db/wait-remote_smtp.lockfile?
You can do as follows :
rm -fv /var/spool/exim/db/*

and then restart exim :
service exim restart

Issue :

On a FreeBSD server with cpanel as the control panel, if mail is not working & you get the following error on restarting exim

server28# /scripts/restartsrv_exim
/libexec/ld-elf.so.1: Shared object “libperl.so” not found, required by “exim”
/libexec/ld-elf.so.1: Shared object “libperl.so” not found, required by “exim”
server28#

Cause :

This error may be caused by a recent cPanel upgrade (upcp).

Fix :

Reinstalling exim did not fix the issue. In one particular case, this was resolved by reinstalling exim from FreeBSD ports.

This problem can be fixed by running the following command :

/usr/local/bin/perl-after-upgrade -f

If this does not fix the issue then try

ln -s /usr/local/cpanel/perl/libperl.so /usr/local/lib

To close the open relay run:

/scripts/fixrelayd
/etc/rc.d/init.d/antirelayd restart
service exim restart

If that doesn’t work then

edit /etc/exim.conf, you should see in line 61 (or close if somebody
changed the default configuration) the definition of which hosts are
allowed relaying :

hostlist relay_from_hosts = 127.0.0.1:192.168.10.0/24

These values will allow localhost and few ips.
Nothing else. Adjust the values according to the requirement.

OR

hostlist relay_from_hosts = 127.0.0.1

This will allow only localhost to have open relay.

That’s all you need to do to change to avoid open relay.

For checking whether it is open relayed do use any one of the following links :-

http://www.rbl.jp/svcheck.php

http://www.checkor.com/

Issue:

After installing clamav on a server, it was showing up the error ”/usr/sbin/clamd: error while loading shared libraries: libiconv.so.2: cannot open shared object file: No such file or directory” while running clamscan.

Fix:

Find the path of  libiconv.so

whereis libiconv.so
libiconv: /usr/local/lib/libiconv.so /usr/local/lib/libiconv.la

Then to check for the shared library dependencies of exim & clamd,

ldd /usr/sbin/exim & ldd /usr/sbin/clamd where I noticed that the library path ”/usr/local/lib” was not included.

For rectifying this,include the path /usr/local/lib in ld.so.conf, then run ldconfig which should create/refresh links to the shared libraries mentioned in ld.so.conf

And also add the following  entry

LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib in the exim startup file (this is not needed though , if the previous step works)

This should fix it!