:1) Discover all Cisco Switches on the Network
Are there any non-Cisco switches in the network? Is CDP turned on on
all of the Cisco switches?
Does the network have multiple subnets? (In the sense of not being
all one flat address space) ?
If you have a Cisco router, do you want the router included in the
report due to it's switching functions? Are any of the routers hybrids,
in the sense of running CatOS on a switching module plus having an
IOS-based routing module in the same device? If so, then to get an
accurate picture, the IOS and CatOS results have to be cross-correlated.
Are any of the target switches running SNMPv1, or are they *all*
running SNMPv2 or SNMPv3? If any of them are SNMPv1,
are the community strings consistant for the switches?
Is it acceptable for the script to probe devices that might not be
switches? In particular, is it acceptable for the script to sequentially
(or otherwise) probe devices in the address range? If any of the
switches are running SNMPv1, is it acceptable for the script to probe
the SNMP port on the devices naming the various valid community
strings in turn to see if it can elicit a reply? Keep in mind that
some boxes might silently record packets being sent to the SNMP port
without replying, so this might allow some boxes to record all the
community strings.
Does the topology involve multiple VLANs? Some of the Cisco devices
require "community string indexing" in order to get the full data.
There are at two different forms of community string indexing,
but I did a search just a few days ago and I was totally unable to find
documentation on the second form (I'm -sure- I read the document before!)
:2) Query all the cisco switches found in 1) and see how many connected
ort are 10Mbps, how many are 100Mbps and how many are Gigabit
What about the ports that are down? If they are set to autonegotiate
or are hard-coded to particular speeds, then does that need to be
recorded somewhere?
Does full duplex vs half-duplex need to be recorded? On some systems,
it is very difficult to tell via SNMP whether a port is in full or
half duplex.
:I need to do this for accounting and billing purpuse.
You know this isn't going to be a quick process? That port states
are going to change right -while- switches are being examined?
And do you really control the infrastructure well enough to be
sure that no-one has put an ACL on one of the switches or a firewall
in place to keep from having the billing data examined?
