RE: [NV-L] Netview discovery processSince NetView is initially developed
with HP OpenView NNM as a base, I can tell you how OpenView works. I guess
this has not been changed in NetView.
The discovery process is handled by the netmon deamon. When the discovery
process starts, the netmon deamon starts by contacting the NetView server's
own SNMP agent. Using SNMP get it will retrive the arp cache. The arp cache
contain a lot of ipadresses to continue to search.
Each node in the collected arp cache is then pinged and if there is a
connection the netmon deamon issues a number of SNMP get commands to collect
information about SysObjectID etc. from the node (approximately the same
information as is received when performing a demand poll).
If the node does not support SNMP or if you have a wrong get community name
set you will not be able to get any of the SNMP information (you will get an
empty square for the node on the desktop).
One of collected MIB variables form the node is the arp cache => new
ipadress to continue the search.
In addition to collecting the first arp cache from the NetView server, nemon
will also contact the default gateway to collect the arp cache information.
The serach will then continue like this, collecting more and more arp
caches, ping the nodes and do a number of SNMP gets.
If you have to few nodes in the environment supporting SNMP or if you have
the wrong SNMP get community name set the discovery process will be very
slow. Please note thai if you by mistake change the SNMP community name of
the SNMP agent at the Netview server (without informing the NetView server)
the netmon deamon will not be able to start at all.
In addition to collecting arp cahces you can also configure netmon to
collect routing tables, eg for WAN routes, but this is not the default
behaviour.
I hope this helps,
regards
Niclas
-----Original Message-----
From: owner-nv-l AT tkg DOT com [mailto:owner-nv-l AT tkg DOT com]On Behalf
Of MERY
Olivier (Neuilly Gestion)
Sent: Monday, May 22, 2000 8:35 AM
To: 'IBM NetView Discussion'
Subject: RE: [NV-L] Netview discovery process
If you have time, you can analyze the traffic generated by the netview
server.
It will give you a good idea of the information gathered from devices.
Regards,
Olivier MERY
CETELEM
20, avenue Georges Pompidou
92595 LEVALLOIS-PERRET Cedex - FRANCE
-----Original Message-----
From: lclark AT us.ibm DOT com [mailto:lclark AT us.ibm DOT com]
Sent: Saturday, May 20, 2000 10:35 PM
To: NV-L AT tkg DOT com
Subject: Re: [NV-L] Netview discovery process
Reggie, I suspect that the information you seek would be considered
intellectual capital by Tivoli. If you are having a specific problem, then
people can usually help you with that, but otherwise, how the code
works is, I am sure, proprietary.
Cordially,
Leslie A. Clark
IBM Global Services - Systems Mgmt & Networking
Detroit
---------------------- Forwarded by Leslie Clark/Southfield/IBM on
05/20/2000 04:32 PM ---------------------------
"Rama, R. (Reggie)" <ReggieR AT nedcor.co DOT za>@tkg.com on 05/18/2000
04:14:02
AM
Please respond to IBM NetView Discussion <nv-l AT tkg DOT com>
Sent by: owner-nv-l AT tkg DOT com
To: "'nv-l AT tkg DOT com'" <nv-l AT tkg DOT com>
cc:
Subject: [NV-L] Netview discovery process
Hello Netview Users
I have searched the list for a detailed explaination of the Netview
(netmon) discovery process but could not find anything detailed enough.
Does anyone have any documentation w.r.t this process .i.e. how does the
netmon daemon go about discovering a network. I require specific details
such as : does/how it uses pings, snmpgets, looks at routing tables, arp
caches, order of the discovery process etc.
Thanks in advance for all assistance.
Regards
Reggie Rama
ESM - Technology & Operations Division
Nedcor Bank Limited (South Africa)
Tel : +27 - 011 - 8813989
Fax : +27 - 011 - 8814113
e-mail : reggier AT nedcor.co DOT za
_________________________________________________________________________
NV-L List information (unsubscribing, policies, posting, digest version,
searchable archives): http://www.tkg.com/nv-l
Since
NetView is initially developed with HP OpenView NNM as a base, I can tell you
how OpenView works. I guess this has not been changed in
NetView.
The
discovery process is handled by the netmon deamon. When the discovery process
starts, the netmon deamon starts by contacting the NetView server's own
SNMP agent. Using SNMP get it will retrive the arp cache. The arp cache contain
a lot of ipadresses to continue to search.
Each
node in the collected arp cache is then pinged and if there is a connection the
netmon deamon issues a number of SNMP get commands to collect information about
SysObjectID etc. from the node (approximately the same information as is
received when performing a demand poll).
If the
node does not support SNMP or if you have a wrong get community name set you
will not be able to get any of the SNMP information (you will get an empty
square for the node on the desktop).
One of
collected MIB variables form the node is the arp cache => new ipadress
to continue the search.
In addition to
collecting the first arp cache from the NetView server, nemon will also contact
the default gateway to collect the arp cache information.
The serach will then
continue like this, collecting more and more arp caches, ping the nodes and do a
number of SNMP gets.
If you have to few
nodes in the environment supporting SNMP or if you have the wrong SNMP get
community name set the discovery process will be very slow. Please note thai if
you by mistake change the SNMP community name of the SNMP agent at the Netview
server (without informing the NetView server) the netmon deamon will not be able
to start at all.
In addition to
collecting arp cahces you can also configure netmon to collect routing tables,
eg for WAN routes, but this is not the default behaviour.
I hope this helps,
regards
Niclas
If you have time, you can analyze the traffic generated by the
netview server. It will give you a good idea of the
information gathered from devices.
Regards,
Olivier MERY CETELEM 20, avenue Georges Pompidou 92595
LEVALLOIS-PERRET Cedex - FRANCE
-----Original Message----- From:
lclark AT us.ibm DOT com [mailto:lclark AT us.ibm DOT com] Sent: Saturday, May 20, 2000 10:35 PM To:
NV-L AT tkg DOT com Subject: Re: [NV-L] Netview discovery
process
Reggie, I suspect that the information you seek would be
considered intellectual capital by Tivoli. If you are
having a specific problem, then people can usually
help you with that, but otherwise, how the code works
is, I am sure, proprietary.
Cordially,
Leslie A. Clark IBM Global Services -
Systems Mgmt & Networking Detroit
---------------------- Forwarded by Leslie
Clark/Southfield/IBM on 05/20/2000 04:32 PM
---------------------------
"Rama, R. (Reggie)" <ReggieR AT nedcor.co DOT za>@tkg.com on
05/18/2000 04:14:02 AM
Please respond to IBM NetView Discussion
<nv-l AT tkg DOT com>
Sent by: owner-nv-l AT tkg DOT com
To: "'nv-l AT tkg DOT com'" <nv-l AT tkg DOT com>
cc: Subject: [NV-L] Netview
discovery process
Hello Netview Users
I have searched the list for a detailed explaination of the
Netview (netmon) discovery process but could not find
anything detailed enough. Does anyone have any
documentation w.r.t this process .i.e. how does the netmon daemon go about discovering a network. I require specific
details such as : does/how it uses pings, snmpgets,
looks at routing tables, arp caches, order of the
discovery process etc.
Thanks in advance for all assistance.
Regards Reggie Rama ESM - Technology & Operations Division Nedcor Bank Limited (South Africa)
Tel : +27 - 011 - 8813989 Fax : +27 -
011 - 8814113 e-mail :
reggier AT nedcor.co DOT za
_________________________________________________________________________
NV-L List information (unsubscribing, policies, posting,
digest version, searchable archives): http://www.tkg.com/nv-l
|