Between the different levels of Netview code, and the different
network evironements out there, I learn something new at every
single customer site. Here's this week's eye-opener:
Wellfleet frame relay does not populate the interface table with
their implementation of sub-interfaces. The physical interface
appears to Netview to be an unnumbered serial interface. So two
undesirable things happen.
First, it tries to draw the unnumbered connections between the
routers. But since these are usually arranged in a many-to-one
configuration, Netview cannot connect them. You end up with those
special networks hanging out all over the place, with names like
routerSysname:<ifIndex>-routerSysname:<ifIndex>. This is mildly
annoying but we can hide them and ignore them since the sub
interfaces are represented by addressed cards somehow. I checked
with Support on this some time ago, and Netview cannot do it.
Second, it switches status polling of the node over to SNMP. This
would be fine if the interface table were populated. But since it
is not, there is nothing to provide status for those subinterfaces.
Cards with addresses are discovered and drawn, but then their
status is not maintained and they end up red. You can force polling
to be SNMP, but you cannot force it NOT to be SNMP.
The solution was to turn off support for Unnumbered in netmon and
rediscover the nodes. This solved both problems. Fortunately this
customer did not need unnumbered support for anything else. But
if the router agent is not going to populate the interface table,
I cannot fault Netview for handling it as it does. I'm impressed
that it could draw the numbered cards at all, since they point to
ifIndex entries that don't even exist. Go Netview!
Cordially,
Leslie A. Clark
IBM Global Services - Systems Mgmt & Networking
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