NMAP Scan Failures

Usage and Config
1

(imported topic written by Mervin91)

Our NMAP scans of remote sites do not return information on host names or possible BES computers and report BES licensed computers as unmanaged clients. Our remote sites are operated under restrictive GPO’s. We’re wondering what kind of permissions are required for NMAP to gather information during scans. Or maybe we have some other kind of issue…We’re stumped.

Thanks,

Merv

2

(imported comment written by BenKus)

Hi Mervin,

NMAP needs no authentication credentials because it uses information available from the network to look up MAC address, hostname, IP, subnet, etc. Not needing credentials and being able to identify ANY device is one of the cool things about the NMAP scan, but if the network does not have the information, NMAP can’t get it either.

In the case of the hostnames, NMAP looks to the DNS servers for the hostname. I think if you try

nslookup

you will find the same result that NMAP gives. The “possible BES computer” field is calculated at import time to look to see if there is a “matching” computer that has already reported as having a BES Client (indicating the BES Client has been stopped or removed). The matching algorithm looks at MAC address to make the match and if the MAC address is unavailable, it looks at hostname/IP address pairs.

Ben

3

(imported comment written by Mervin91)

Hello Ben,

Thanks for the response. When I review unmanaged assets I can see both MAC and IP addresses reported for my workstations/devices. It appears as if you are suggesting a failure at the main server when the “possible BES computer” field is calculated. If that is the case how do I troubleshoot? It doesn’t seem as if the DNS issue would prevent the field from populating, or am I off track?

Merv

4

(imported comment written by BenKus)

Hi Mervin,

What version of BES are you running and what version of the UAImporter-NMAP.exe are you using (should be in your BES Server folder under “AssetDiscovery”).

Ben

5

(imported comment written by Mervin91)

Howdy Ben,

Importer version is 6.0.19.6, BES version is 6.0.21.5.

Merv