Hello Everybody!
In the last month we migrated from NetView/AIX V 5.1.3 to V 7.1.2 , AIX
Version 4.3.3 .
During handling with topologie changes I discovered an interesting
phenomena.
I would like to ask the list-members if they discovered the same thing. It
is quite difficult to express, so please hold on to this long text:
In our network the bigger routers have an ISDN-backupline. The ISDN-port is
discovered as 'isSerialInterface = TRUE'. In the time Netview discoveres
the router the backup-connection is down, the router is discovered via the
main-connection, a synchronous connection (leased line).
I dont want the ISDN-port to be pinged, so I unmanaged it. I must also
mention, that we use Nortel-routers and the ISDN Backup Line Support
(dormant status) doesn't work for them. Also the SNMP-status-polling
doesn't work, because with our router-config the current interface status
is not reflected in the MIB-variable netview reads.
Because Netview discoveres the correspondig interface in the
ISDN-Backup-Router in the headquarter a line is drawn between
ISDN-Backup-Router and the router in the field. When I unmanage this line
(that means the network) then the whole router is unmanaged!
I tried this with other routers that are connected via more than one
sync-line, that means via more serial interfaces and found out following:
For example router B is connected via a synchronous leased line (serial
interface) to router A. As backup router B is also connected to router C
by the same way.
When I unmanage the connection (=network) between A and B ...
...only the corresponding serial interface on router B gets unmanaged -
when both routers are in the same submap!
...the whole router B (all interfaces) will get unmanaged - when router B
is in a submap of this submap (we use many submaps to organize the
topologie of our 800 routers). In this case it is not possible, to managed
the interface for it self, the Option 'Manage' is grey. First the network
must be managed, now it's possible. This is a difference to Version 5.
There I could manage an interface although the corresponding network was
unmanaged!
I think, this is not correct! Because what happens now is realy currious:
Okay, I'm used to live with unlogical tools ;-) ...
So I manage router B again, unmanage the interface to router A (maybe it
sounds unlogical for you that the interface becomes managed this way, but
it works! - so I must unmanage it ). So the drawn line between A and B
remaines unmanaged and router B is again green.
But now: When router B is down or unreachable, the IP-Status of the
unmanaged serial interface becomes also 'Unreachable' or 'Critical'!
This shows a 'Tools-Display Object Information...'. And after the router is
up again this status will not change to 'Unmanaged' again! It will remain
in 'Critical' or 'Normal' but on the topologie-map it still appears as
unmanaged.
And for this reason netmon is pinging this interface again (I made a
netmon-trace) and ISDN-Calls are opened!
So two questions:
a) Is it logical that the whole router becomes unmanaged when I unmanage
one of this connections to the 'upstream' router?(Remeber - this happens
only when the downstream-router is in an other submap)
b) Why doesn't change the IP-Status of an unmanaged Interface in the
explained situation not again to unmanaged?
Sincerely
Wolfgang Nilz
ARZ - Allgemeines Rechenzentrum
Abt. Netzwerk - WAN
Tschamlerstr. 2, A-6020 Innsbruck
Tel. ++43 5345 - 1292
mailto:wolfgang.nilz@arz.co.at
http://www.arz.co.at
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