Hi there, I'm trying to scan and map a network with NTM v2.2 , everything his working well but not for one host who appear has an unknown host. My network is made of one Cisco 2901 router, multiple Cisco 2960 switch and some AP Cisco based in one Class C network.. I'm using NTM from a computer outside of this network under a IPSEC VPN connection. I can see every network device (switch and AP), but my router appear as an unknown host. I use this configuration to enable SNMP on every device: "snmp-server community version 2c RO" In NTM I add this string to the SNMP credentials. I'm using always the same string on every device of the network.. I'm using the option "ignore nodes that only respond to ICMP...". Everything his working well I can see every link between device, bandwidth information etc. Exept for the router who appear as an unknown host and I have no information of the bandwidth of the link between this router and the "core" switch... Can you plz try to help me ? (btw, sorry for my bad english...)

Community
- Command Central
- MVP Program
- Monthly Mission
- Blogs
- Groups
- Events
- Media Vault
Products
- Observability
- Network Management
- Application Management
- IT Security
- IT Service Management
- System Management
- Database Management
Content Exchange
- SolarWinds Platform
- Server & Application Monitor
- Database Performance Analyzer
- Server Configuration Monitor
- Network Performance Monitor
- Network Configuration Manager
- SQL Sentry
- Web Help Desk
Free Tools & Trials
Store

Problem : Unknown Host (Cisco 2901)

Hi there,

I'm trying to scan and map a network with NTM v2.2 , everything his working well but not for one host who appear has an unknown host.

My network is made of one Cisco 2901 router, multiple Cisco 2960 switch and some AP Cisco based in one Class C network..

I'm using NTM from a computer outside of this network under a IPSEC VPN connection.

I can see every network device (switch and AP), but my router appear as an unknown host.

I use this configuration to enable SNMP on every device:

"snmp-server community <string> version 2c RO"

In NTM I add this string to the SNMP credentials.

I'm using always the same string on every device of the network..

I'm using the option "ignore nodes that only respond to ICMP...".

Everything his working well I can see every link between device, bandwidth information etc. Exept for the router who appear as an unknown host and I have no information of the bandwidth of the link between this router and the "core" switch...

Can you plz try to help me ?

(btw, sorry for my bad english...)

Find more posts tagged with

Accepted answers

All comments

airsun

Hi noiz,

Normally, NTM can't discover nodes that doesn't respond to SNMP request. To check if your device responds to SNMP try this:

1. Click Help -> Support tools -> Grab SNMPWALK.

2. Put the IP address of the said router and the correct Community string.

3. Click Scan and make sure that you can download OID information.

If you receive an error, let us know.

noiz

Thanks for your answer @airsun I will try tomorrow

noiz

I got a lot of information in a text file...

But I don't know how to interpret the result ... Which information should help me ?

noiz

It's ok I found an issue !!!!!

I just added the IP address of the router in "Network Selection" in the case "Free From IPs" and the node have now the correct name and IP Address on the map !!

Only one problem left on the map , I have two links between this router and my core switch, this link appear as an etherchannel link (But LACP his not enable ....) If anyone have an issue for fix this problem ?

airsun

I am glad that you were able to fix the issue discovering the said device. For the link issue, can you send a screenshot of what you are saying and what should it be? Thanks.