TACTIC logs

TACTIC logs

Overview

In a default installation tactic stores its logs in a single file. For proper maintenance, this file must be rotated by the host operating system. This action must be set in the host operating system. As tactic has no facility to control the log files it makes as of yet, it may be necessary to configure an external tool to rotate logs.

Prerequisites

The host operating system must have a facility to rotate text logs on a regular chronological basis.

Configuration

Logrotate is used as a tool to rotate text files on a chronological basis. The tool allows automatic rotation, compression, removal and mailing of log files.

Directives

This is a partial list of logrotate directives.

  • missingok: If the log file is missing, go on to the next log file without issuing an error message.

  • copytruncate: Truncate the original log file to zero size in place after creating a copy, instead of moving the old log file and optionally creating a new one

  • rotate 7 : Log files are rotated 7 times before being removed or mailed to the address specified in a mail directive. If count is 0, old versions are removed rather then rotated.

  • compress: Old versions of log files are compressed with gzip to save disk space.

  • notifempty: Do not rotate the log if it is empty

  • sharedscripts postrotate /etc/init.d/lighttpd reload endscript:

Default configuration

Logrotate's main configuration file /etc/logrotate.conf

Applies the main configuration settings from this file to all log rotation settings, unless overridden by individual directives on a per-log basis.

# see "man logrotate" for details
# rotate log files weekly
weekly
# keep 4 weeks worth of backlogs
rotate 4
# create new (empty) log files after rotating old ones
create
# uncomment this if you want your log files compressed
#compress
# RPM packages drop log rotation information into this directory
include /etc/logrotate.d
# no packages own wtmp -- we'll rotate them here
/var/log/wtmp {
monthly
create 0664 root utmp
rotate 1
}
Example Service Configuration

This is an example logrotate configuration for HTTP. The configuration file is /etc/logrotate.d/httpd

/var/log/httpd/*.log {
 weekly
 rotate 52
 compress
  missingok
  notifempty
  sharedscripts
  postrotate
      /bin/kill -HUP `cat /var/run/httpd.pid 2>/dev/null` 2> /dev/null || true    endscript
}

On the example linux system, service or server specific configurations are stored in /etc/logrotate.d directory. For example here is sample apache logrotate configuration file:

In this example, HTTP logs are not deleted until they are at least a year old, and are rotated on a weekly basis. There are other configuration options available, but they will not be discussed in this tutorial. Please look online for more information on these other options. Depending on the requirement, each log file may be handled at different intervals.

The lines between postrotate and endscript (both of which must appear on lines by themselves) are executed after the log file is rotated. These directives may only appear inside a log file definition. In our case we are reloading lighttpd.

Example TACTIC configuration

The configuration goal is get logrotate to get the tactic log files rotated for our needs and requirements.

This is an example logrotate configuration for HTTP. The configuration file is /etc/logrotate.d/tactic

Remember to restart the logrotate services after any additions to logrotate configuration.

/home/apache/tacticTemp/log/stdout.log {
    notifempty
    daily
    rotate 365
    missingok
    copytruncate
    create 0600 apache apache
}