PLANET WGSW-52040 - Manual (Page 498)

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zone, and log host.
 The log information is classified to four level of severities by which the information will be filtered
 According to the severity level the log information can be auto outputted to corresponding log channel.
66.7.1.1 Log Output Channel
So far the system log can be outputted the log information through four channels:
 Through Console port to the local console
 Output the log information to remote Telnet terminal or monitor, this function is good for remote
maintenance
 Assign a proper log buffer zone inside the switch, for record the log information permanently or
temporarily
 Configure the log host, the log system will directly send the log information to the log host, and save it in
files to be viewed at any time
Among above log channels, users rarely use the console monitor, but will commonly choose the Telnet
terminal to monitor the system operation status. However information outputted from these channels are of
low traffic capacity and can not be recorded for later view. The other two channels---the log buffer zone and
log host channel are two important channels
SDRAM (Synchronous Dynamic Random Access Memory) and NVRAM (Non Vulnerable Random Access
Memory) is provided inside the switch as two part of the log buffer zone, The two buffer zone record the log
information in a circuit working pattern, namely when log information need to be recorded exceeds the buffer
size, the oldest log information will be erased and replaced by the new log information, information saved in
NVRAM will stay permanently while those in SDRAM will lost when the system restarts or encounter an power
failure. Information in the log buffer zone is critical for monitoring the system operation and detecting
abnormal states.
Note: the NVRAM log buffer may not exist on some switches, which only have the SDRAM log buffer
zone.
It is recommended to use the system log server. By configuring the log host on the switch, the log can
be sent to the log server for future examination.
66.7.1.2 Format and Severity of the Log Information
The log information format is compatible with the BSD syslog protocol, so we can record and analyze the log
by the systlog (system log protect session) on the UNIX/LINUX, as well as syslog similar applications on PC.
The log information is classified into eight classes by severity or emergency procedure. One level per value
and the higher the emergency level the log information has, the smaller its value will be. For example, the
level of critical is 2, and warning is 4, debugging is leveled at 7, so the critical is higher than warnings which no