Adding User-Defined Filter-Based Monitors - HP StorageWorks MSA 2/8 - SAN Switch User Manual

Adding User-Defined Filter-Based Monitors

In addition to the standard filters (read, write, read/write, and frame count), you
can create custom filters to qualify frames for statistics gathering to fit your own
special needs.
To define a custom filter, use the perfAddUserMonitor telnet command.
With this command, you must specify a series of offsets, masks, and values. The
following actions are performed. For all incoming frames, the switch:
You can specify up to six different offsets for each port, and up to four values to
compare against each offset.
If more than one offset is required to properly define a filter, the bytes found at
each offset must match one of the given values for the filter to increment its
counter. If one or more of the given offsets does not match any of the given values,
the counter does not increment.
The value of the offset must be between 0 and 63, in decimal format. Byte 0
indicates the first byte of the Start of Frame (SOF), byte 4 is the first byte of the
frame header, and byte 28 is the first byte of the payload. Thus only the SOF,
frame header, and first 36 bytes of payload may be selected as part of a filter
definition.
Offset 0 is a special case, which can be used to monitor the first 4 bytes of the
frame (SOF). When the offset is 0, the values are from 0–7, indicating the
following:
0
1
2
3
4
5
6
7
Advanced Performance Monitoring Version 3.1.x/4.1.x User Guide
locates the byte found in the frame at the specified offset
applies the mask to the byte found in the frame
compares the value with the given values in the perfAddUserMonitor
command
increments the filter counter if a match is found
SOFf
SOFc1
SOFi1
SOFn1
SOFi2
SOFn2
SOFi3
SOFn3
Using Advanced Performance Monitoring
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