What is kjournald
kjournald:
It is for the journaling feature of the EXT3 file system. Kjournald is the journaling kernel thread for ext3 filesystem. One for each mounted ext3 filesystem.
# ps auxfw |grep kjournald
root 494 0.0 0.0 0 0 ? S< Jun17 27:45 \_ [kjournald]
root 1827 0.0 0.0 0 0 ? S< Jun17 0:00 \_ [kjournald]
root 2124 0.0 0.0 0 0 ? S< Jun17 0:23 \_ [kjournald]
Chkconfig
The chkconfig command can also be used to activate and deactivate services. If you use the chkconfig –list command, you will see a list of system services and whether they are started (on) or stopped (off) in runlevels 0-6 (at the end of the list, you will see a section for the services managed by xinetd.
If you use chkconfig –list to query a service managed by xinetd, you will see whether the xinetd service is enabled (on) or disabled (off). For example, the following command shows that finger is enabled as an xinetd service:
$ chkconfig –list finger
finger on
More importantly, chkconfig can be used to set a service to be started (or not) in a specific runlevel. For example, to turn nscd off in runlevels 3, 4, and 5, use the command:
chkconfig –level 345 nscd off
Unable to get information from zmcontrol
This issue is mainly occurring due to the incorrect permission of /opt/zimbra/redolog and /opt/zimbra/redolog/redo.log.
Do the following steps:
[root@zimbra bin]# ls -l /opt/zimbra/redolog
total 8
drwxr-x— 2 root root 4096 Mar 20 13:17 archive
-rw-r—– 1 root root 1292 Apr 11 19:11 redo.log
The chower ship of /opt/zimbra/redolog/redo.log and /opt/zimbra/redolog must be zimbra.
chown -R zimbra.zimbra /opt/zimbra/redolog/
[root@zimbra bin]# ls -l /opt/zimbra/redolog
total 8
drwxr-x— 2 zimbra zimbra 4096 Mar 20 19:17 archive
-rw-r—– 1 zimbra zimbra 1292 Apr 11 19:59 /opt/zimbra/redolog/redo.log
Now try the “zmcontrol status” and “zmcontrol start”. This will work fine now.
Note: If you are facing difficulty in running “zmcontrol status”, try the exact path “/opt/zimbra/bin/zmcontrol status”.
Flush mail queue in sendmail
To flush the mail queue manually in sendmail servers, use
$ /usr/sbin/sendmail -q -v
Better way
Make a backup of the existing queue directory.
Create the ‘mqueue’ directory with the same permissions and ownership. Then, type in
$ /usr/sbin/sendmail -q -v -OQueueDirectory=/var/spool/mqueue.bak
You can use the same command to flush any sendmail queue as some servers have multiple queue setup like mqueue, mqueue.site, clientmqueue, q1, q2 etc.
Change SMTP source IP address in sendmail
1. Edit sendmail.cf search for ClientPortOptions
2. Change
#O ClientPortOptions=Family=inet, Address=x.x.x.x
to
O ClientPortOptions=Family=inet, Address=
3. Restart sendmail
4. Verify by sending a mail and checking the full header
CLIENT_OPTIONS(`field1=value1,field2=value2,…’) in sendmail.mc file is equivalent to ClientPortOptions in the sendmail.cf file.
