ITEM: AS6680L
/usr/OV/conf/oid_to_type and /usr/OV/conf/C/oid_to_sym
Question: We are in the process of discovering several Cisco routers (functioning as
protocol translators) in our network. Some of these routers are being
discovered with the "Gateway" symbol and some with the "Terminal" symbol, even
though they are all functioning in the same manner. The sysObjectID is
different for the routers that are discovered as "Gateway" symbols
(1.3.6.1.4.1.9.1.17) and "Terminal" symbols (1.3.6.1.4.1.9.1.3).
Now, I placed the sysObjectId 1.3.6.1.4.1.9.1.17 into the
/usr/OV/conf/oid_to_type file and in the /usr/OV/conf/C/oid_to_sym file so that
the "Terminal" symbol would represent these objects in the maps, but this did
not work. I then realized that this particular MIB (1.3.6.1.4.1.9.1.17) is not
in the cisco MIB file that is loaded on the management system. Does this
particular MIB object need to be defined and loaded into Netview in order for
Netview to represent the object correctly in the maps? Why? If not, what else
would cause this problem?
During the course of investigating this problem, I have generated more
questions regarding the mapping of objects to symbols in the
Netview maps:
- Where and how are the "rules" defined for Netview to know which symbol AND
in which maps a specific SNMP object should be placed?
- In detail, what does Netview "look at" when it initially discovers a new SNMP
object to determine its placement in the submaps?
Here is some information that may diminish the confusion somewhat.
* The netmon daemon gets the "system.sysObjectID.0" information
from a node's SNMP agent, and netmon puts that information in
the "SNMP OBJECT ID" field for that node in the IP topology
database.
* The netmon daemon compares the sysObjectId from the MIB with the entry
in the /usr/OV/conf/oid_to_type to determine the node's type. For
instance, if the sysObjectId in the oid_to_type file has a "G" flag,
then netmon will add a "GATEWAY" flag in the "FLAGS" field in the IP
Topology database.
* The ipmap application is the application that draws the symbol(s)
for the node on the map. ipmap has two decisions to make. These
are:
1) where to draw the symbol
2) what symbol to draw
* To determine where to draw the symbol, ipmap looks at the FLAGS field be drawn on the Network and Segment level submaps. Nodes without
special flags will be treated as normal nodes, and will only be drawn
on the Segment level submaps.
* To determine what type of symbol to draw, the ipmap application uses
the SNMP OBJECT ID from the IP Topology database. ipmap compares the
sysObjectId with the entry in the /usr/OV/conf/C/oid_to_sym file to
determine what kind of symbol to draw for a node.
For example, my machine is drawn as a workstation node, because my
sysObjectId is
1.3.6.1.4.1.2.3.1.2.1.1.2, and my oid_to_sym file says
1.3.6.1.4.1.2.3.1.2.1.1.2:Computer:Workstation \# IBM AIX 3.2 workstation
There are a couple of things to remember here:
1) There is nothing stopping you from making oid_to_sym and oid_to_type
"inconsistent". For instance, you could put a "G" flag in the
oid_to_type file that says that a node is a gateway, and then you
could put the "Connector:Hub" symbol in the oid_to_symbol. So,
you'd have a hub symbol being drawn on the Internet, Network, and
Segment submaps, just like a gateway. This won't cause problems
for NetView, but it may be confusing to users.
the IP Topology database to ensure that the flags and sysObjectId
are set correctly. You may need to check the community name and
demand poll the device. Use the "ovtopodump -rl \" command
to check the IP Topology database.
3) If you change the oid_to_sym and/or oid_to_type AFTER the node is
discovered, the best thing to do is this:
stop the user interface and netmon
run "ovtopofix -A"
Bring the user interface back up
2) If a symbol is not being drawn as you would expect, first check
in the IP Topology database. If the FLAG is "GATEWAY", then this
node will be drawn on the IP Internet, Network, and Segment level
submaps. If the FLAG is "BRIDGE" or "STAR_HUB", then the node will
Support Line: /usr/OV/conf/oid_to_type and /usr/OV/conf/C/oid_to_sym ITEM: AS6680L
Dated: December 1995 Category: N/A
This HTML file was generated 99/06/24~13:30:25
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