Posts Tagged ‘squid cache’

How to force logrorate process logs / Make logrotate changes take effect immediately

Sunday, April 10th, 2016

how-to-force-logrorate-to-process-logs-make-logrorate-changes-take-effect-immediately-log-rotate-300x299

Dealing with logrorate as admins we need to change or add new log-rorate configurations (on most Linux distributions configs are living uder
/etc/logrotate.d/
 

logrotate uses crontab to work. It's scheduled work, not as daemon, so usually no need to reload its configuration.
When the crontab executes logrotate, it will use your new config file automatically.

Most of the logrotate setups I've seen on various distros runs out of the /etc/cron.daily

$ ls -l /etc/cron.daily/logrotate 
-rwxr-xr-x 1 root root 180 May 18  2014 /etc/cron.daily/logrotate

Here is content of cron job scheduled script:

$ cat /etc/cron.daily/logrorate

#!/bin/sh /usr/sbin/logrotate /etc/logrotate.conf EXITVALUE=$? if [ $EXITVALUE != 0 ]; then /usr/bin/logger -t logrotate "ALERT exited abnormally with [$EXITVALUE]" fi exit 0

Configurations change to lograte configs takes effect on next crontab run,
but what If you need to test your config you can also execute logrotate
on your own with below ommand:

 

logrotate -vf /etc/logrotate.conf 

If you encounter some issues with just modified or newly added logrorate script to check out the status of last logrorate executing bunch of log-rotate scripts run on Debian  / Ubuntu etc. deb based Linux:

cat /var/lib/logrotate/status

Or on RHEL, Fedora, CentOS Linux


cat /var/lib/logrotate.status

logrotate state -- version 2

 

"/var/log/syslog" 2016-4-9
"/var/log/dpkg.log" 2016-4-1
"/var/log/unattended-upgrades/unattended-upgrades.log" 2012-9-20
"/var/log/unattended-upgrades/unattended-upgrades-shutdown.log" 2013-5-17
"/var/log/apache2/mailadmin.pc-freak.net-access.log" 2012-9-19
"/var/log/snort/portscan.log" 2012-9-12
"/var/log/apt/term.log" 2016-4-1
"/var/log/squid/access.log" 2015-3-21
"/var/log/mysql/mysql-slow.log" 2016-4-9
"/var/log/debug" 2016-4-3
"/var/log/mysql.log" 2016-4-9
"/var/log/squid/store.log" 2015-3-21
"/var/log/apache2/mailadmin.pc-freak.net-error.log" 2012-9-19
"/var/log/daemon.log" 2016-4-3
"/var/log/munin/munin-update.log" 2016-4-9
"/var/log/unattended-upgrades/unattended-upgrades*.log" 2013-5-16
"/var/log/razor-agent.log" 2015-2-19
"/var/log/btmp" 2016-4-1
"/var/log/squid/*.log" 2014-11-24
"/var/log/munin/munin-graph.log" 2016-4-9
"/var/log/mysql/mysql.log" 2012-9-12
"/var/log/munin/munin-html.log" 2016-4-9
"/var/log/clamav/freshclam.log" 2016-4-3
"/var/log/munin/munin-node.log" 2016-1-23
"/var/log/mail.info" 2016-4-3
"/var/log/apache2/other_vhosts_access.log" 2016-4-3
"/var/log/exim4/rejectlog" 2012-9-12
"/var/log/squid/cache.log" 2015-3-21
"/var/log/messages" 2016-4-3
"/var/log/stunnel4/stunnel.log" 2012-9-19
"/var/log/apache2/php_error.log" 2012-10-21
"/var/log/ConsoleKit/history" 2016-4-1
"/var/log/rsnapshot.log" 2013-4-15
"/var/log/iptraf/*.log" 2012-9-12
"/var/log/snort/alert" 2012-10-17
"/var/log/privoxy/logfile" 2016-4-3
"/var/log/auth.log" 2016-4-3
"/var/log/postgresql/postgresql-8.4-main.log" 2012-10-21
"/var/log/apt/history.log" 2016-4-1
"/var/log/pm-powersave.log" 2012-11-1
"/var/log/proftpd/proftpd.log" 2016-4-3
"/var/log/proftpd/xferlog" 2016-4-1
"/var/log/zabbix-agent/zabbix_agentd.log" 2016-3-25
"/var/log/alternatives.log" 2016-4-7
"/var/log/mail.log" 2016-4-3
"/var/log/kern.log" 2016-4-3
"/var/log/privoxy/errorfile" 2013-5-28
"/var/log/aptitude" 2015-5-6
"/var/log/apache2/access.log" 2016-4-3
"/var/log/wtmp" 2016-4-1
"/var/log/pm-suspend.log" 2012-9-20
"/var/log/snort/portscan2.log" 2012-9-12
"/var/log/mail.warn" 2016-4-3
"/var/log/bacula/log" 2013-5-1
"/var/log/lpr.log" 2012-12-12
"/var/log/mail.err" 2016-4-3
"/var/log/tor/log" 2016-4-9
"/var/log/fail2ban.log" 2016-4-3
"/var/log/exim4/paniclog" 2012-9-12
"/var/log/tinyproxy/tinyproxy.log" 2015-3-25
"/var/log/munin/munin-limits.log" 2016-4-9
"/var/log/proftpd/controls.log" 2012-9-19
"/var/log/proftpd/xferreport" 2012-9-19
"/var/spool/qscan/qmail-queue.log" 2013-5-15
"/var/log/user.log" 2016-4-3
"/var/log/apache2/error.log" 2016-4-3
"/var/log/exim4/mainlog" 2012-10-16
"/var/log/privoxy/jarfile" 2013-5-28
"/var/log/cron.log" 2016-4-3
"/var/log/clamav/clamav.log" 2016-4-3

 

The timestamp date next to each of the rotated service log is when the respective log was last rorated

It is also a handy thing to rorate only a certain service log, lets say clamav-server, mysql-server, apache2 and nginx
 


logrorate /etc/logrorate.d/clamav-server
logrorate /etc/logrorate.d/mysql-server
logrotate /etc/logrotate.d/nginx

How to clear Squid Proxy Cache on Debian and Ubuntu

Saturday, July 16th, 2011

Squid proxy cache clear logo

It was necessery to clean up some squid cache for some proxy users on a Debian host. Until now I’ve used to run only custom build Squid server on Slackware Linux.

Thus I was curious if Debian guys were smart enough to implement a proxy cache cleaning option as an option to be passed on to squid’s init script.

Honestly I was quite suprised squid clear cache option is not there;

squid-cache:~# /etc/init.d/squid3
Usage: /etc/init.d/squid3 {start|stop|reload|force-reload|restart}
squid-cache:/#

As it was not embedded into init script I still hoped, there might be some Debian way to do the proxy cache clearing, so I spend some 10 minutes checking online as well as checked in squid3‘s manual just to find there is no specific command or Debian accepted way to clean squid’s cache.

Since I couldn’t find any Debian specific, way I did it the old fashioned way 😉 (deleted directory/file structures in /var/spool/squid3/* and used squid’s -z option, to recreate the swap directories.

Here is how:

squid-cache:~# /etc/init.d/squid3 stop;
squid-cache:~# rm -Rf /var/spool/squid3/*;
squid-cache:~# squid3 -z; /etc/init.d/squid3 start

Finally I was quite amazed to realize, there was not even a crontab script to periodically clear and re-create proxy cache.

My previous experience with maintaning an office Squid proxy cache has prooved, that periodic cache clean ups are very helpful, especially to resolve issues with cached unreslovable DNS entries in the server.
Clearing up squid cache every week or something, guarantees that failure to resolve certain hosts at certain times would not stay unresolvable like forever 😉

In that manner of thougths, I decided to put the following crontab which will twice a month clear up proxy’s cache, to possibly solve some failed squid DNS issues.

squid-cache:~# crontab -u root -l > file;
echo '00 04 12,26 * * /etc/init.d/squid3 stop; rm -Rf /var/spool/squid3/*; squid3 -z; /etc/init.d/squid3 start >/dev/null 2>&1'
>> file; crontab file

By the way, implementing the squid clear cache in Debian and Ubuntu ‘s init scripts and putting a periodic proxy clear up cron, seems like a feature worthy to be proposed to the distro developers and hopefully be embbed in some of the upcoming distro releases 😉