Fluke Network Router - Manual (Page 36)

User’s Guide – version 1.6 NetWatch
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This service type is one of the most powerful supported by NetWatch. Along with
testing the status of an interface, a service can be configured to read usage
information for the interface. This allows you to create graphs of bandwidth
utilisation for an interface, and allows the map applet to colour links according to
their percentage utilisation.
When you add the SNMP Interface Test service type there are several options you can
configure to control how the discovered services will work.
Average Response Time: This is the average time in milliseconds you would
expect a successful check of the status and utilisation of a single interface to
take. This is used to decide when to raise an alert that a device is responding
slowly. If you are unsure of this, leave the default value of 200 milliseconds. If
you are monitoring a device across a slow WAN link, or if you experience a
lot of slow response time alerts on the device it may be a good idea to raise
this value.
Maximum Response Time: This is the maximum number of milliseconds
NetWatch will wait for a response from the device before retrying a check or
giving up. After the third timeout NetWatch will stop trying to check the status
of an interface and report a timeout as the status of that interface. You may
find that some interfaces are reporting timeouts and some report a proper
status; this can happen when a device is very busy and is ignoring a lot of the
SNMP requests it receives. You may wish to change this value if you find this
is the case; a shorter maximum response time with a higher number of retries
would be more likely to get a status for each interface (at the expense of
slightly more network traffic).
SNMP Community String: This is the read-only community set up on your
device. Usually a device supporting SNMP will have two communities, which
are rather like passwords, one of which only allows the reading of values and
the other that allows reading and writing of some values. In a great many cases
the community that supports reading only is the default value, “public”. If you
find that the SNMP Interface Test is not working you may need to check this
value. Note that this value belongs to the service type on the device; you can’t
change it for an individual service.
Use Netwatch Server Clock By Default, Netwatch uses the time on the
device being managed to record various time related statistics. This is the ideal
solution in most situations. However on some highly utilised devices the time
reported can be incorrect. In this situation it is advised that you use the time
on the Netwatch server.