IBM RS/6000 SP, Problem Determination Manual

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This soft copy for use by IBM employees only.
If the new size limit is smaller than the log file size currently
used, errdemon renames the current log file to <name>.old
and creates a new error log file with the specified size limit.
- B < b u f f s i z e > Uses the number of bytes specified by the <buffsize>
parameter for the in-memory buffer used by the error log
device driver. The specified buffer size is saved in the error
log configuration database.
If the <buffsize> parameter is larger than the buffer size
currently in use, then the in-memory buffer will be
immediately increased.
If the <buffsize> parameter is smaller than the buffer size
currently in use, then the new size is put into effect the next
time errdemon is started after the system is rebooted.
The size you specify is always rounded up to the next
integral multiple of the memory page size (4KB). The
memory used for the error log device driver
′
s in-memory
buffer is not available for use by other processes (the buffer
is “pinned”).
Be careful not to impact your system
′
s performance by
making the buffer excessively large. On the other hand, if
you make the buffer too small, the buffer can become full if
error entries arrive faster than they can be read from the
buffer and put into the log file. When the buffer is full, new
entries are discarded until space becomes available in the
buffer. When this situation occurs, errdemon creates an
error log entry to inform you about the problem. You can
easily correct this problem by enlarging the buffer.
Note: On the RS/6000 SP system, thin and wide nodes behave differently
regarding NVRAM and power loss.
You can use the command
errclear
to remove entries from the system error
log.
Note that errdemon is normally started during system initialization. Stopping the
error logging daemon can cause error data to be temporarily stored in internal
buffers. These buffers can be overwritten before the error data is recorded in
the error log file.
If you have specified a new error log file size and you want to generate an error
report from the old one, you can use the
-i
option of the
errpt
command.
Note that the buffer cannot be made smaller than the hard-coded default of 8 KB.
Syslogd Daemon
The syslogd daemon reads a datagram socket and sends each message line to
a destination described by the /etc/syslog.conf configuration file. The syslogd
daemon reads the configuration file when it is activated and when it receives a
hangup signal.
The syslogd daemon creates the /etc/syslog.pid file, which contains a single line
with the command process ID used to end or configure the syslogd daemon. A
terminate signal sent to the syslogd daemon ends the daemon, and syslogd will
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SP PD Guide