Log Destination
Each Rendezvous daemon and component process—rvd
, rvrd
, rvsd
, rvsrd
, rvtrace
—produces log output. The content of log output varies, but the semantics of command line options that affect logging are identical for all of these components:
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When all of the command line options that affect logging are absent, daemons send log output to stderr . |
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When -logfile log_filename is present, daemons send log output to the file you specify, namely log_filename . |
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When -log-max-size size is present and non-zero, daemons use a log rotation regimen. For details, see Log Rotation below. The parameter -log-max-rotations n determines the number files in the rotation. |
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When -log-config config_log_filename is present, daemons log duplicate copies of configuration changes to the file you specify, namely config_log_filename . Daemons never rotate nor remove this file, so a permanent record of this important information remains. (This parameter is available only for rvrd , rvsd and rvsrd .) |
Log Rotation
To enable log rotation, you must specify a non-zero value for -log-max-size
. (When absent, the default value is zero.)
The command line option -log-max-size
size
limits the growth of log files. The size
parameter specifies the maximum disk space (in kilobytes) that a log file can occupy (approximately) before it is rotated.
The command line option -log-max-rotations
n
specifies the number of log files in the rotation sequence. Notice that the storage devoted to log files can grow at most to approximately size
*
(
n
+1)
.
The daemon rotates the log files according to this renaming plan:
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The parameter -logfile log_filename specifies the name of the current log file, which receives log output. For example, for rvd one might specify rvd.log (without any numerical suffix). This name also becomes the base for a sequence of rotation files. |
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When the current log file reaches its maximum size, the daemon rotates log files: |
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It closes the current log file (in our example, rvd.log ). |
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It appends the next available numerical suffix to the base name, and renames the full log file with that name; for example, rvd.log1 . Suffixes begin with 1 , and continue through n before rotating back to 1. This renaming operation overwrites any existing file from a previous rotation. |
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It opens a new current log file (once again, rvd.log ). |
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When the daemon terminates and restarts, logging resumes by appending to the current log file, but the rotation state is reset (that is, the first rotation overwrites the file with suffix 1 ). |
You can determine the most recent file by comparing either packet time stamps within the files, or file modification times.
Log Rotation Backward Compatibility
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The command line option -log-rotate total_size is deprecated in release 7.5, and will become obsolete in a subsequent release. We recommend migrating to the new log rotation parameters at your earliest convenience.
In the meantime, we preserve backward compatibility by converting the value of this deprecated parameter to corresponding values of the new parameters:
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-log-rotate total_size retains its old meaning—specifying the total size for all log files. The maximum size for each individual file in the rotation is total_size /10 . |
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If both old and new parameters are present, the new parameters take precedence (overriding the old parameter). |
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Current Log Page
The browser interfaces for all daemon components include a Current Log page, which displays the most recent 4 kilobytes of log output (for convenience).