Mount Linux partition in Windows
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Package Auto Update Notifications
Install apticron
Type the following command at a shell prompt:
# apt-get update
# apt-get install apticron
Configure apticron to send email notifications
The default coniguration file is located at /etc/apticron/apticron.conf. Open file using text editor:
# vi /etc/apticron/apticron.conf
You need to set email address to email the notification as follows:
EMAIL="your_email@domain.com"
================================================================
sample configuration file
# apticron.conf
#
# set EMAIL to a list of addresses which will be notified of impending updates
#
EMAIL="admin@myhost.com"
#
# Set LISTCHANGES_PROFILE if you would like apticron to invoke apt-listchanges
# with the --profile option. You should add a corresponding profile to
# /etc/apt/listchanges.conf
#
# LISTCHANGES_PROFILE="apticron"
#
# Set SYSTEM if you would like apticron to use something other than the output
# of "hostname -f" for the system name in the mails it generates
#
# SYSTEM="foobar.example.com"
#
# Set IPADDRESSNUM if you would like to configure the maximal number of IP
# addresses apticron displays. The default is to display 1 address of each
# family type (inet, inet6), if available.
#
# IPADDRESSNUM="1"
#
# Set IPADDRESSES to a whitespace seperated list of reachable addresses for
# this system. By default, apticron will try to work these out using the
# "ip" command
#
# IPADDRESSES="192.10.2.1 2001:db8:1:2:3::1"
Save and close the file. /etc/cron.daily/apticron is the cron script for executing apticron daily and it will send you notfication when updates available.
Type the following command at a shell prompt:
# apt-get update
# apt-get install apticron
Configure apticron to send email notifications
The default coniguration file is located at /etc/apticron/apticron.conf. Open file using text editor:
# vi /etc/apticron/apticron.conf
You need to set email address to email the notification as follows:
EMAIL="your_email@domain.com"
================================================================
sample configuration file
# apticron.conf
#
# set EMAIL to a list of addresses which will be notified of impending updates
#
EMAIL="admin@myhost.com"
#
# Set LISTCHANGES_PROFILE if you would like apticron to invoke apt-listchanges
# with the --profile option. You should add a corresponding profile to
# /etc/apt/listchanges.conf
#
# LISTCHANGES_PROFILE="apticron"
#
# Set SYSTEM if you would like apticron to use something other than the output
# of "hostname -f" for the system name in the mails it generates
#
# SYSTEM="foobar.example.com"
#
# Set IPADDRESSNUM if you would like to configure the maximal number of IP
# addresses apticron displays. The default is to display 1 address of each
# family type (inet, inet6), if available.
#
# IPADDRESSNUM="1"
#
# Set IPADDRESSES to a whitespace seperated list of reachable addresses for
# this system. By default, apticron will try to work these out using the
# "ip" command
#
# IPADDRESSES="192.10.2.1 2001:db8:1:2:3::1"
Save and close the file. /etc/cron.daily/apticron is the cron script for executing apticron daily and it will send you notfication when updates available.
SSH Manipulations
SSH Banner Message
Login as root and edit ssh config file
# vi /etc/ssh/sshd_config
Find this variable in the config file
# Banner /some/locations/file
Uncomment it and save the file
Restart openssh server
# /etc/init.d/ssh restart
SSH Timeout
echo “TMOUT=300 >> /etc/bashrc
echo “readonly TMOUT” >> /etc/bashrc
echo “export TMOUT” >> /etc/bashrc
Login as root and edit ssh config file
# vi /etc/ssh/sshd_config
Find this variable in the config file
# Banner /some/locations/file
Uncomment it and save the file
Restart openssh server
# /etc/init.d/ssh restart
SSH Timeout
echo “TMOUT=300 >> /etc/bashrc
echo “readonly TMOUT” >> /etc/bashrc
echo “export TMOUT” >> /etc/bashrc
Extract a single file from single tar ball
Extracting Specific Files
Extract a file called etc/default/sysstat from config.tar.gz tarball
#tar -ztvf config.tar.gz
#tar -zxvf config.tar.gz etc/default/sysstat
#tar -xvf {tarball.tar} {path/to/file}
This is also valid
#tar --extract --file={tarball.tar} {file}
Extract a directory called css from cbz.tar
##tar --extract --file=cbz.tar css
Wildcard based extracting
You can also extract those files that match a specific globbing pattern (wildcards). For example, to extract from cbz.tar all files that begin with pic, no matter their directory prefix, you could type:
#tar -xf cbz.tar --wildcards --no-anchored 'pic*'
To extract all php files, enter
#tar -xf cbz.tar --wildcards --no-anchored '*.php'
Where,
-x: instructs tar to extract files.
-f: specifies filename / tarball name.
-v: Verbose (show progress while extracting files).
-j : filter archive through bzip2, use to decompress .bz2 files.
-z: filter archive through gzip, use to decompress .gz files.
–wildcards: instructs tar to treat command line arguments as globbing patterns.
–no-anchored: informs it that the patterns apply to member names after any / delimiter.
Tar listing
Tar command provides the option to list files inside compressed tar ball. However mtools includes command called lz which gunzips and shows a listing of a gzip’d tar’d archive without extracting files.
For example, display listing of file called backup.tar.gz type command:
#lz backup.tar.gz
As you see lz provides a listing of a gzip’d tar’d archive, that is a tar archive compressed with the gzip command. It is not strictly necessary on Debian GNU/Linux (or other Linux/BSD/Solaris oses), because the GNU tar(1) program provides the same capability with the command:
#tar -tzf backup.tar.gz
Extract a file called etc/default/sysstat from config.tar.gz tarball
#tar -ztvf config.tar.gz
#tar -zxvf config.tar.gz etc/default/sysstat
#tar -xvf {tarball.tar} {path/to/file}
This is also valid
#tar --extract --file={tarball.tar} {file}
Extract a directory called css from cbz.tar
##tar --extract --file=cbz.tar css
Wildcard based extracting
You can also extract those files that match a specific globbing pattern (wildcards). For example, to extract from cbz.tar all files that begin with pic, no matter their directory prefix, you could type:
#tar -xf cbz.tar --wildcards --no-anchored 'pic*'
To extract all php files, enter
#tar -xf cbz.tar --wildcards --no-anchored '*.php'
Where,
-x: instructs tar to extract files.
-f: specifies filename / tarball name.
-v: Verbose (show progress while extracting files).
-j : filter archive through bzip2, use to decompress .bz2 files.
-z: filter archive through gzip, use to decompress .gz files.
–wildcards: instructs tar to treat command line arguments as globbing patterns.
–no-anchored: informs it that the patterns apply to member names after any / delimiter.
Tar listing
Tar command provides the option to list files inside compressed tar ball. However mtools includes command called lz which gunzips and shows a listing of a gzip’d tar’d archive without extracting files.
For example, display listing of file called backup.tar.gz type command:
#lz backup.tar.gz
As you see lz provides a listing of a gzip’d tar’d archive, that is a tar archive compressed with the gzip command. It is not strictly necessary on Debian GNU/Linux (or other Linux/BSD/Solaris oses), because the GNU tar(1) program provides the same capability with the command:
#tar -tzf backup.tar.gz
Locking and Unlocking User Accounts in Linux
To lock, you can use the follow command
# passwd -l username
To Unlock the same account
# passwd -u username
Creating command Alias in Linux
Creating aliases is very easy. You can either enter them at the command line as you're working, or more likely, you'll put them in one of your startup files, like your .bashrc file, so they will be available every time you log in.
I created the l alias above by entering the following command into my .bashrc file:
alias l="ls -al"
As you can see, the syntax is very easy:
1. Start with the alias command
2. Then type the name of the alias you want to create
3. Then an = sign, with no spaces on either side of the =
4. Then type the command (or commands) you want your alias to execute when it is run. This can be a simple command, or can be a powerful combination of commands.
Sample aliases example
To get you going, here is a list of sample aliases I use all the time. I've pretty much just copied them here from my .bashrc file:
alias l="ls -al"
alias lm="ls -al|more"
alias html="cd /web/apache/htdocs/devdaily/html"
alias logs="cd /web/apache/htdocs/devdaily/logs"
alias qp="ps auxwww|more"
alias nu="who|wc -l"
alias aug="ls -al|grep Sep|grep -v 2010"
I created the l alias above by entering the following command into my .bashrc file:
alias l="ls -al"
As you can see, the syntax is very easy:
1. Start with the alias command
2. Then type the name of the alias you want to create
3. Then an = sign, with no spaces on either side of the =
4. Then type the command (or commands) you want your alias to execute when it is run. This can be a simple command, or can be a powerful combination of commands.
Sample aliases example
To get you going, here is a list of sample aliases I use all the time. I've pretty much just copied them here from my .bashrc file:
alias l="ls -al"
alias lm="ls -al|more"
alias html="cd /web/apache/htdocs/devdaily/html"
alias logs="cd /web/apache/htdocs/devdaily/logs"
alias qp="ps auxwww|more"
alias nu="who|wc -l"
alias aug="ls -al|grep Sep|grep -v 2010"
Ubuntu: Very useful Commands
Command privileges
sudo command - run command as root
sudo su – root shell open
sudo su user – open shell as a user
sudo -k – forget your password sudo
gksudo command – sudo visual dialog (GNOME)
kdesudo command – sudo visual dialog (KDE)
sudo visudo – edit / etc / sudoers
gksudo nautilus – root file manager (GNOME)
kdesudo konqueror – root file manager (KDE)
passwd – change your password
Command Network
ifconfig – displays information network
iwconfig – displays information from wireless
sudo iwlist scan – scan wireless networks
sudo /etc/init.d/networking restart – reset the network
(file) /etc/network/interfaces – manual configuration
ifup interface – bring online interface
ifdown interface – disable interface
Commands Display
sudo /etc/init.d/gdm restart – reset X (Gnome)
sudo /etc/init.d/kdm restart – reset X (KDE)
(file) /etc/X11/xorg.conf – show Configuration
sudo dpkg-reconfigure - reconfigure xserver-xorg-phigh - reset configuration X
Ctrl+Alt+Bksp – X display reset if frozen
Ctrl+Alt+FN – switch to tty N
Ctrl+Alt+F7 – switch back to X display
Commands Service System
start service – service to start work (Upstart)
stop service – service to stop working (Upstart)
status service – check if service is running (Upstart)
/etc/init.d/service start – start service (SysV)
/etc/init.d/service stop – stop service (SysV)
/etc/init.d/service status – check service (SysV)
/etc/init.d/service restart – reset service (SysV)
runlevel – get current runlevel
Commands for Firewall
ufw enable – turn on the firewall
ufw disable – turn off the firewall
ufw default allow – allow all connections by default
ufw default deny – drop all connections by default
ufw status – current rules and
ufw allow port – to allow traffic on port
ufw deny port – port block
ufw deny from ip – ip block
Command System
lsb_release -a – get the version of Ubuntu
uname -r – get kernel version
uname -a – get all the information kernel
Commands for Package Manager
apt-get update – refresh updates available
apt-get upgrade – update all packages
apt-get dist-upgrade – version update
apt-get install pkg – installing pkg
apt-get remove pkg – uninstall pkg
apt-get autoremove – removing packages obsotletos
apt-get -f install – try to fix packages
dpkg –configure -a – try to fix a broken package
dpkg -i pkg.deb – install file pkg.deb
(file) /etc/apt/sources.list – list of repositories APT
Special Packages For commands
ubuntu-desktop – Setting the standard Ubuntu
kubuntu-desktop – KDE Desktop
xubuntu-desktop – desktop XFCE
ubuntu-minimal – core earnings Ubuntu
ubuntu-standard – the standard utilities Ubuntu
ubuntu-restricted-extras – not free, but useful
kubuntu-restricted-extras – ditto KDE
xubuntu-restricted-extras – ditto XFCE
build-essential – packages used to compile
linux-image-generic – latest generic kernel image
linux-headers-generic – latest headlines
Applications commands
nautilus – File Manager (GNOME)
dolphin – File Manager (KDE)
konqueror – Web browser (KDE)
kate – text editor (KDE)
gedit – text editor (GNOME)
sudo command - run command as root
sudo su – root shell open
sudo su user – open shell as a user
sudo -k – forget your password sudo
gksudo command – sudo visual dialog (GNOME)
kdesudo command – sudo visual dialog (KDE)
sudo visudo – edit / etc / sudoers
gksudo nautilus – root file manager (GNOME)
kdesudo konqueror – root file manager (KDE)
passwd – change your password
Command Network
ifconfig – displays information network
iwconfig – displays information from wireless
sudo iwlist scan – scan wireless networks
sudo /etc/init.d/networking restart – reset the network
(file) /etc/network/interfaces – manual configuration
ifup interface – bring online interface
ifdown interface – disable interface
Commands Display
sudo /etc/init.d/gdm restart – reset X (Gnome)
sudo /etc/init.d/kdm restart – reset X (KDE)
(file) /etc/X11/xorg.conf – show Configuration
sudo dpkg-reconfigure - reconfigure xserver-xorg-phigh - reset configuration X
Ctrl+Alt+Bksp – X display reset if frozen
Ctrl+Alt+FN – switch to tty N
Ctrl+Alt+F7 – switch back to X display
Commands Service System
start service – service to start work (Upstart)
stop service – service to stop working (Upstart)
status service – check if service is running (Upstart)
/etc/init.d/service start – start service (SysV)
/etc/init.d/service stop – stop service (SysV)
/etc/init.d/service status – check service (SysV)
/etc/init.d/service restart – reset service (SysV)
runlevel – get current runlevel
Commands for Firewall
ufw enable – turn on the firewall
ufw disable – turn off the firewall
ufw default allow – allow all connections by default
ufw default deny – drop all connections by default
ufw status – current rules and
ufw allow port – to allow traffic on port
ufw deny port – port block
ufw deny from ip – ip block
Command System
lsb_release -a – get the version of Ubuntu
uname -r – get kernel version
uname -a – get all the information kernel
Commands for Package Manager
apt-get update – refresh updates available
apt-get upgrade – update all packages
apt-get dist-upgrade – version update
apt-get install pkg – installing pkg
apt-get remove pkg – uninstall pkg
apt-get autoremove – removing packages obsotletos
apt-get -f install – try to fix packages
dpkg –configure -a – try to fix a broken package
dpkg -i pkg.deb – install file pkg.deb
(file) /etc/apt/sources.list – list of repositories APT
Special Packages For commands
ubuntu-desktop – Setting the standard Ubuntu
kubuntu-desktop – KDE Desktop
xubuntu-desktop – desktop XFCE
ubuntu-minimal – core earnings Ubuntu
ubuntu-standard – the standard utilities Ubuntu
ubuntu-restricted-extras – not free, but useful
kubuntu-restricted-extras – ditto KDE
xubuntu-restricted-extras – ditto XFCE
build-essential – packages used to compile
linux-image-generic – latest generic kernel image
linux-headers-generic – latest headlines
Applications commands
nautilus – File Manager (GNOME)
dolphin – File Manager (KDE)
konqueror – Web browser (KDE)
kate – text editor (KDE)
gedit – text editor (GNOME)
Installing GRUB using grub-install
In order to install GRUB under a UNIX-like OS (such as gnu), invoke the program grub-install as the superuser (root).
The usage is basically very simple. You only need to specify one argument to the program, namely, where to install the boot loader. The argument has to be either a device file (like ‘/dev/hda’). For example, under Linux the following will install GRUB into the MBR of the first IDE disk:
# grub-install /dev/hda
Likewise, under GNU/Hurd, this has the same effect:
# grub-install /dev/hd0
But all the above examples assume that GRUB should put images under the /boot directory. If you want GRUB to put images under a directory other than /boot, you need to specify the option --boot-directory. The typical usage is that you create a GRUB boot floppy with a filesystem. Here is an example:
# mke2fs /dev/fd0
# mount -t ext2 /dev/fd0 /mnt
# mkdir /mnt/boot
# grub-install --boot-directory=/mnt/boot /dev/fd0
# umount /mnt
Some BIOSes have a bug of exposing the first partition of a USB drive as a floppy instead of exposing the USB drive as a hard disk (they call it “USB-FDD” boot). In such cases, you need to install like this:
# losetup /dev/loop0 /dev/sdb1
# mount /dev/loop0 /mnt/usb
# grub-install --boot-directory=/mnt/usb/bugbios --force --allow-floppy /dev/loop0
This install doesn't conflict with standard install as long as they are in separate directories.
Note that grub-install is actually just a shell script and the real task is done by grub-mkimage and grub-setup. Therefore, you may run those commands directly to install GRUB, without using grub-install. Don't do that, however, unless you are very familiar with the internals of GRUB. Installing a boot loader on a running OS may be extremely dangerous.
Windows: control panel shortcuts
Accessibility Options........................access.cpl
Add New Hardware ........................sysdm.cpl
Add/Remove Programs ........................appwiz.cpl
Date/Time Properties ........................timedate.cpl
Display Properties ........................desk.cpl
FindFast ........................findfast.cpl
Fonts Folder ........................fonts
Internet Properties ........................inetcpl.cpl
Joystick Properties ........................joy.cpl
Keyboard Properties ........................main.cpl keyboard
Microsoft Exchange ........................mlcfg32.cpl
Microsoft Mail Post Office...................wgpocpl.cpl
Modem Properties ........................modem.cpl
Mouse Properties ........................main.cpl
Multimedia Properties........................mmsys.cpl
Network Properties ........................netcpl.cpl
Password Properties ........................password.cpl
PC Card ........................main.cpl pc card (PCMCIA)
Power Management.............................main.cpl power
Power Management.............................powercfg.cpl
Printers Folder ........................printers
Regional Settings ........................intl.cpl
Scanners and Cameras ........................sticpl.cpl
Sound Properties ........................mmsys.cpl sounds
System Properties ........................sysdm.cpl
Add New Hardware ........................sysdm.cpl
Add/Remove Programs ........................appwiz.cpl
Date/Time Properties ........................timedate.cpl
Display Properties ........................desk.cpl
FindFast ........................findfast.cpl
Fonts Folder ........................fonts
Internet Properties ........................inetcpl.cpl
Joystick Properties ........................joy.cpl
Keyboard Properties ........................main.cpl keyboard
Microsoft Exchange ........................mlcfg32.cpl
Microsoft Mail Post Office...................wgpocpl.cpl
Modem Properties ........................modem.cpl
Mouse Properties ........................main.cpl
Multimedia Properties........................mmsys.cpl
Network Properties ........................netcpl.cpl
Password Properties ........................password.cpl
PC Card ........................main.cpl pc card (PCMCIA)
Power Management.............................main.cpl power
Power Management.............................powercfg.cpl
Printers Folder ........................printers
Regional Settings ........................intl.cpl
Scanners and Cameras ........................sticpl.cpl
Sound Properties ........................mmsys.cpl sounds
System Properties ........................sysdm.cpl
Exim Mail Commands in Details
Print a count of the messages in the queue:
[root@localhost]# exim -bpc
Print a listing of the messages in the queue (time queued, size, message-id, sender, recipient):
[root@localhost]# exim -bp
Print a summary of messages in the queue (count, volume, oldest, newest, domain, and totals):
[root@localhost]# exim -bp | exiqsumm
Print what Exim is doing right now:
[root@localhost]# exiwhat
Test how exim will route a given address:
[root@localhost]# exim -bt alias@localdomain.com
#user@thishost.com
<-- alias@localdomain.com
router = localuser, transport = local_delivery
[root@localhost]# exim -bt user@thishost.com
user@thishost.com
router = localuser, transport = local_delivery
[root@localhost]# exim -bt user@remotehost.com
router = lookuphost, transport = remote_smtp
host mail.remotehost.com [1.2.3.4] MX=0
Run a pretend SMTP transaction from the command line, as if it were coming from the given IP address. This will display Exim's checks, ACLs, and filters as they are applied. The message will NOT actually be delivered.
[root@localhost]# exim -bh 192.168.11.22
Display all of Exim's configuration settings:
[root@localhost]# exim -bP
Searching the queue with exiqgrep
Exim includes a utility that is quite nice for grepping through the queue, called exiqgrep. Learn it. Know it. Live it. If you're not using this, and if you're not familiar with the various flags it uses, you're probably doing things the hard way, like piping `exim -bp` into awk, grep, cut, or `wc -l`. Don't make life harder than it already is.
First, various flags that control what messages are matched. These can be combined to come up with a very particular search.
Use -f to search the queue for messages from a specific sender:
[root@localhost]# exiqgrep -f [luser]@domain
Use -r to search the queue for messages for a specific recipient/domain:
[root@localhost]# exiqgrep -r [luser]@domain
Use -o to print messages older than the specified number of seconds. For example, messages older than 1 day:
[root@localhost]# exiqgrep -o 86400 [...]
Use -y to print messages that are younger than the specified number of seconds. For example, messages less than an hour old:
[root@localhost]# exiqgrep -y 3600 [...]
Use -s to match the size of a message with a regex. For example, 700-799 bytes:
[root@localhost]# exiqgrep -s '^7..$' [...]
Use -z to match only frozen messages, or -x to match only unfrozen messages.
There are also a few flags that control the display of the output.
Use -i to print just the message-id as a result of one of the above two searches:
[root@localhost]# exiqgrep -i [ -r | -f ] ...
Use -c to print a count of messages matching one of the above searches:
[root@localhost]# exiqgrep -c ...
Print just the message-id of the entire queue:
[root@localhost]# exiqgrep -i
Managing the queue
The main exim binary (/usr/sbin/exim) is used with various flags to make things happen to messages in the queue. Most of these require one or more message-IDs to be specified in the command line, which is where `exiqgrep -i` as described above really comes in handy.
Start a queue run:
[root@localhost]# exim -q -v
Start a queue run for just local deliveries:
[root@localhost]# exim -ql -v
Remove a message from the queue:
[root@localhost]# exim -Mrm <message-id> [ <message-id> ... ]
Freeze a message:
[root@localhost]# exim -Mf <message-id> [ <message-id> ... ]
Thaw a message:
[root@localhost]# exim -Mt <message-id> [ <message-id> ... ]
Deliver a message, whether it's frozen or not, whether the retry time has been reached or not:
[root@localhost]# exim -M <message-id> [ <message-id> ... ]
Deliver a message, but only if the retry time has been reached:
[root@localhost]# exim -Mc <message-id> [ <message-id> ... ]
Force a message to fail and bounce as "cancelled by administrator":
[root@localhost]# exim -Mg <message-id> [ <message-id> ... ]
Remove all frozen messages:
[root@localhost]# exiqgrep -z -i | xargs exim -Mrm
Remove all messages older than five days (86400 * 5 = 432000 seconds):
[root@localhost]# exiqgrep -o 432000 -i | xargs exim -Mrm
Freeze all queued mail from a given sender:
[root@localhost]# exiqgrep -i -f luser@example.tld | xargs exim -Mf
View a message's headers:
[root@localhost]# exim -Mvh <message-id>
View a message's body:
[root@localhost]# exim -Mvb <message-id>
View a message's logs:
[root@localhost]# exim -Mvl <message-id>
Add a recipient to a message:
[root@localhost]# exim -Mar <message-id> <address> [ <address> ... ]
Edit the sender of a message:
[root@localhost]# exim -Mes <message-id> <address>
Searching the logs with exigrep
The exigrep utility (not to be confused with exiqgrep) is used to search an exim log for a string or pattern. It will print all log entries with the same internal message-id as those that matched the pattern, which is very handy since any message will take up at least three lines in the log. exigrep will search the entire content of a log entry, not just particular fields.
One can search for messages sent from a particular IP address:
[root@localhost]# exigrep '<= .* \[12.34.56.78\] ' /path/to/exim_log
Search for messages sent to a particular IP address:
[root@localhost]# exigrep '=> .* \[12.34.56.78\]' /path/to/exim_log
This example searches for outgoing messages, which have the "=>" symbol, sent to "user@domain.tld". The pipe to grep for the "<=" symbol will match only the lines with information on the sender - the From address, the sender's IP address, the message size, the message ID, and the subject line if you have enabled logging the subject. The purpose of doing such a search is that the desired information is not on the same log line as the string being searched for.
[root@localhost]# exigrep '=> .*user@domain.tld' /path/to/exim_log | fgrep '<='
Generate and display Exim stats from a logfile:
[root@localhost]# eximstats /path/to/exim_mainlog
Same as above, with less verbose output:
[root@localhost]# eximstats -ne -nr -nt /path/to/exim_mainlog
Same as above, for one particular day:
[root@localhost]# fgrep YYYY-MM-DD /path/to/exim_mainlog | eximstats
To delete all queued messages containing a certain string in the body:
[root@localhost]# grep -lr 'a certain string' /var/spool/exim/input/ | \
sed -e 's/^.*\/\([a-zA-Z0-9-]*\)-[DH]$/\1/g' | xargs exim -Mrm
Note that the above only delves into /var/spool/exim in order to grep for queue files with the given string, and that's just because exiqgrep doesn't have a feature to grep the actual bodies of messages. If you are deleting these files directly, YOU ARE DOING IT WRONG! Use the appropriate exim command to properly deal with the queue.
If you have to feed many, many message-ids (such as the output of an `exiqgrep -i` command that returns a lot of matches) to an exim command, you may exhaust the limit of your shell's command line arguments. In that case, pipe the listing of message-ids into xargs to run only a limited number of them at once. For example, to remove thousands of messages sent from hero@linux-geek.com:
[root@localhost]# exiqgrep -i -f '<hero@linux-geek.com>' | xargs exim -Mrm
[root@localhost]# exim -bpc
Print a listing of the messages in the queue (time queued, size, message-id, sender, recipient):
[root@localhost]# exim -bp
Print a summary of messages in the queue (count, volume, oldest, newest, domain, and totals):
[root@localhost]# exim -bp | exiqsumm
Print what Exim is doing right now:
[root@localhost]# exiwhat
Test how exim will route a given address:
[root@localhost]# exim -bt alias@localdomain.com
#user@thishost.com
<-- alias@localdomain.com
router = localuser, transport = local_delivery
[root@localhost]# exim -bt user@thishost.com
user@thishost.com
router = localuser, transport = local_delivery
[root@localhost]# exim -bt user@remotehost.com
router = lookuphost, transport = remote_smtp
host mail.remotehost.com [1.2.3.4] MX=0
Run a pretend SMTP transaction from the command line, as if it were coming from the given IP address. This will display Exim's checks, ACLs, and filters as they are applied. The message will NOT actually be delivered.
[root@localhost]# exim -bh 192.168.11.22
Display all of Exim's configuration settings:
[root@localhost]# exim -bP
Searching the queue with exiqgrep
Exim includes a utility that is quite nice for grepping through the queue, called exiqgrep. Learn it. Know it. Live it. If you're not using this, and if you're not familiar with the various flags it uses, you're probably doing things the hard way, like piping `exim -bp` into awk, grep, cut, or `wc -l`. Don't make life harder than it already is.
First, various flags that control what messages are matched. These can be combined to come up with a very particular search.
Use -f to search the queue for messages from a specific sender:
[root@localhost]# exiqgrep -f [luser]@domain
Use -r to search the queue for messages for a specific recipient/domain:
[root@localhost]# exiqgrep -r [luser]@domain
Use -o to print messages older than the specified number of seconds. For example, messages older than 1 day:
[root@localhost]# exiqgrep -o 86400 [...]
Use -y to print messages that are younger than the specified number of seconds. For example, messages less than an hour old:
[root@localhost]# exiqgrep -y 3600 [...]
Use -s to match the size of a message with a regex. For example, 700-799 bytes:
[root@localhost]# exiqgrep -s '^7..$' [...]
Use -z to match only frozen messages, or -x to match only unfrozen messages.
There are also a few flags that control the display of the output.
Use -i to print just the message-id as a result of one of the above two searches:
[root@localhost]# exiqgrep -i [ -r | -f ] ...
Use -c to print a count of messages matching one of the above searches:
[root@localhost]# exiqgrep -c ...
Print just the message-id of the entire queue:
[root@localhost]# exiqgrep -i
Managing the queue
The main exim binary (/usr/sbin/exim) is used with various flags to make things happen to messages in the queue. Most of these require one or more message-IDs to be specified in the command line, which is where `exiqgrep -i` as described above really comes in handy.
Start a queue run:
[root@localhost]# exim -q -v
Start a queue run for just local deliveries:
[root@localhost]# exim -ql -v
Remove a message from the queue:
[root@localhost]# exim -Mrm <message-id> [ <message-id> ... ]
Freeze a message:
[root@localhost]# exim -Mf <message-id> [ <message-id> ... ]
Thaw a message:
[root@localhost]# exim -Mt <message-id> [ <message-id> ... ]
Deliver a message, whether it's frozen or not, whether the retry time has been reached or not:
[root@localhost]# exim -M <message-id> [ <message-id> ... ]
Deliver a message, but only if the retry time has been reached:
[root@localhost]# exim -Mc <message-id> [ <message-id> ... ]
Force a message to fail and bounce as "cancelled by administrator":
[root@localhost]# exim -Mg <message-id> [ <message-id> ... ]
Remove all frozen messages:
[root@localhost]# exiqgrep -z -i | xargs exim -Mrm
Remove all messages older than five days (86400 * 5 = 432000 seconds):
[root@localhost]# exiqgrep -o 432000 -i | xargs exim -Mrm
Freeze all queued mail from a given sender:
[root@localhost]# exiqgrep -i -f luser@example.tld | xargs exim -Mf
View a message's headers:
[root@localhost]# exim -Mvh <message-id>
View a message's body:
[root@localhost]# exim -Mvb <message-id>
View a message's logs:
[root@localhost]# exim -Mvl <message-id>
Add a recipient to a message:
[root@localhost]# exim -Mar <message-id> <address> [ <address> ... ]
Edit the sender of a message:
[root@localhost]# exim -Mes <message-id> <address>
Searching the logs with exigrep
The exigrep utility (not to be confused with exiqgrep) is used to search an exim log for a string or pattern. It will print all log entries with the same internal message-id as those that matched the pattern, which is very handy since any message will take up at least three lines in the log. exigrep will search the entire content of a log entry, not just particular fields.
One can search for messages sent from a particular IP address:
[root@localhost]# exigrep '<= .* \[12.34.56.78\] ' /path/to/exim_log
Search for messages sent to a particular IP address:
[root@localhost]# exigrep '=> .* \[12.34.56.78\]' /path/to/exim_log
This example searches for outgoing messages, which have the "=>" symbol, sent to "user@domain.tld". The pipe to grep for the "<=" symbol will match only the lines with information on the sender - the From address, the sender's IP address, the message size, the message ID, and the subject line if you have enabled logging the subject. The purpose of doing such a search is that the desired information is not on the same log line as the string being searched for.
[root@localhost]# exigrep '=> .*user@domain.tld' /path/to/exim_log | fgrep '<='
Generate and display Exim stats from a logfile:
[root@localhost]# eximstats /path/to/exim_mainlog
Same as above, with less verbose output:
[root@localhost]# eximstats -ne -nr -nt /path/to/exim_mainlog
Same as above, for one particular day:
[root@localhost]# fgrep YYYY-MM-DD /path/to/exim_mainlog | eximstats
To delete all queued messages containing a certain string in the body:
[root@localhost]# grep -lr 'a certain string' /var/spool/exim/input/ | \
sed -e 's/^.*\/\([a-zA-Z0-9-]*\)-[DH]$/\1/g' | xargs exim -Mrm
Note that the above only delves into /var/spool/exim in order to grep for queue files with the given string, and that's just because exiqgrep doesn't have a feature to grep the actual bodies of messages. If you are deleting these files directly, YOU ARE DOING IT WRONG! Use the appropriate exim command to properly deal with the queue.
If you have to feed many, many message-ids (such as the output of an `exiqgrep -i` command that returns a lot of matches) to an exim command, you may exhaust the limit of your shell's command line arguments. In that case, pipe the listing of message-ids into xargs to run only a limited number of them at once. For example, to remove thousands of messages sent from hero@linux-geek.com:
[root@localhost]# exiqgrep -i -f '<hero@linux-geek.com>' | xargs exim -Mrm
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