Red Hat Enterprise Linux 5 Administration Unleashed

Logging Connections 353Only the filename is required. Optionally, set how many old log files are kept ondisk with versions . Set to unlimited to keep all old log files. Ifversions is not configured, no backup log files are saved. The size option must beset for this to work.If size is set and versions is set to more than 0, a new log file is created when itreaches the given size and the old file is renamed .0. If the log filereaches the given size and versions is not set to start a new file, the log file remainson disk, but it is not written to after it reaches the given size. The log file must berenamed manually or somehow reduced in size for logging to resume. If size is notset, the log file size is not limited. When setting, the number should be followed byk for kilobytes, m for megabytes, and so on such as 10m for 10 megabytes.. Send messages to a specific syslog facility:syslog Replace with the syslog facility to use: auth, authpriv, cron, daemon,kern, lpr, mail, news, syslog, user, uucp, and local0 through local7. The list isalso in the syslog.conf man page. The /etc/syslog.conf file must then be modifiedto determine how syslog handles the messages through the set facility. Refer tothe syslog.conf man page for details.. Send messages to standard error:stderr16This method is usually only used when named is running in the foreground whileyou are actively monitoring stderr, such as during debugging.. Throw out messages and do not write them anywhere:nullOptionally, if writing messages to a file, a log severity level can be set with the severity statement inside the logging statement to determine what type of messages areprocessed by each channel. If syslog is being used, the priority set for it is also factoredinto the decision.When customizing logging, the print-category, print-severity, and print-time statementscan each be optionally set to yes or no. If print-category is set to yes, the categoryof the message is logged. If print-severity is set to yes, the severity level of eachmessages is logged. If print-time is set to yes, a time stamp is written with each message.The category statement inside the logging statement is used to associate channels withlog message categories. As shown in Listing 16.1, the statement takes the form:category If a channel is not listed for a category, the predefined channels of default_syslog anddefault_debug are used unless the default category is redefined. Otherwise, replace with a semicolon-separated list of predefined and/or user-defined channels.