Discover the node by whichever address you think of as the 'main'
address. Do this by putting it in the seedfile, stopping netmon,deleting
the node, and starting netmon.
Set up name resolution so that all of the addresses resolve
to that same name. Set up name resolution so that the name always
resolves to the same address. In /etc/hosts, that is done by putting
the address you like ahead of the rest of the addresses. Now if
Netview gets the urge to change the name of the router because it
heard from one of the other interfaces, the lookup of that address will
just give back the same name so nothing will change. This can be done
in DNS, but it is often done incorrectly, or is not important enough to the
DNS people to care about. Or they may be doing 'round-robin' name
resolution. That's why I suggest testing it out in /etc/hosts. It is simpler.
I don't know exactly what kicks off the change. And I would not
bother naming a very large number of interfaces. Just the ones
that it seems to switch to. Changing names cause problems for
data collection, event processing, etc. Also, Netview only goes looking
for a name for the first address it discovers a node by. It does not
search the address table looking for other names. If it hears from an
address, it will look that up. There are a lot of lookups associated
with an incoming trap. But most of your virtual addresses netview will
never hear from.
That's all I know about that. Someone else?
Cordially,
Leslie A. Clark
IBM Global Services - Systems Mgmt & Networking
Thanks Leslie, but before I proceed to make changes I would like to
understand what is going on. Lets say I have a router with several
interfaces register under different names; only its main interface is in a
seed file for discovery purposes. Is Netview going to change the router's
name to one of the interface's name? since any interface could reply to
pings or other queries. The router has only one physical ATM interface with
hundreds of LEC's. The IpAdEntIfIndex variable shows every interface
number and network. If Netview uses values from ifIndexes and ipIndexes for
reverse dns lookups, any registered interface name on the router could
become the router's name; I think this is what is happening. Is there any
way to avoid this? Or I have to delete the dns entries for these interfaces.
Thanks for any explanation.
At 12:59 AM 5/13/99 -0400, you wrote:
>I would just about bet that it is a DNS issue. Or maybe HSRP, if you are
doing
>that. I would carefully check the resolution, forward and backward, of each
>address on each router. Some address on Router 1 at some point is resolving
>to the name you have registered for one of the interfaces on Router 2.
>
>When you say you are giving each interface a different name for
administrative
>purposes, do you mean yours or for users? If I were you, I would put both of
>those routers in /etc/hosts, all address, all with the same exact name,
and if
>they are in DNS, also put those ong names in the hosts file as aliases so you
>are sure all possible resolution will be done by the host file, both
forward and
>backward. Make the file /etc/netsvc.conf with the entry 'hosts=local,bind' to
>make
>it check hosts before dns.) Delete them and rediscover them.Then you
should see
>Netview handle them properly and you will know that it is a dns problem.
>
>When you are deciding which addresses go on which routers, use the mib
>browser or rnetstat or snmpwalk to check the sysname so you know for sure
>which router you are querying, and pull the address table to see which
addresses
>to assign to which router. Maybe your paperwork is wrong! It is my firm
belief
>that when Netview shows you something goofy in your network, 97% of the time
>there is something goofy in your network.
>
>Also, you want to get to V5.1.1 as soon as you can. V5.0 is short lots of
fixes,
>including some for hsrp support.
>
>Cordially,
>
>Leslie A. Clark
>IBM Global Services - Systems Mgmt & Networking
>
>
>
>
>Hello there, the environment is Netview 5.0 under AIX 4.2.1. RS-6000 240.
>
>The scenario:
>There are two routers; Router1 has only its main interface registered in
>the dns (i.e.: 111.222.1.1), Router2 has every interface (approx. 10)
>registered in the dns under different names; this is done mainly for
>administrative purposes.
>
>The problem:
>Our Router1 for some reason changes its name on the topology map to the
>name of one of the interfaces of Router2 (always the same interface name).
>This is a nightmare for us since we trigger alarms based on the device name
>under the topology map.
>
>Is this a Netview issue or unique to our network? In a test server I'm
>running 5.1.1 with the same results. I have run database utilities but the
>device after a while picks the wrong name again.
>
>I don't think this is a dns issue either.
>
>Thanks for any help.
>
>.
>
>.
>Jorge A. Jiles
>Network Analyst
>Computing & Network Services
>University of Alberta
>Edmonton, Alberta
>Canada
>
.
Jorge A. Jiles
Network Analyst
Computing & Network Services
University of Alberta
Edmonton, Alberta
Canada
|