Can I use SNMP to discovery devices if I dont have LA

Question

I am trying to discover some Windows and Linux machines that are provided by a 3rd part vendor so I dont have Local Admin access.

Providing I have the community string can discover these devices and find information like OS, HDD utilization, machine name?

Kind Regards,

Warren Gardner

Answer 1

The typical SNMP discovery is simply a number of SNMP GET/GET-NEXT requests to query the list of predefined OIDs. The procedure scans the range of IP addresses (UDP port 161) using the same SNMP security parameters. For SNMP v1/v2C the only parameter you need to specify is Read Community string. For SNMPv3 you have to specify security level, auth/priv protocol, username and password and some other parameters.

Please note that there is no standard for SNMP discovery. So usually the results of discovery are very limited (subset of RFC1213 - MIB-2):

• sysName,
• sysDescr,
• sysLocation
• network interfaces

The advanced SNMP discovery procedure is usually implemented in commercial software/NMS and includes extended information from Cisco IOS, printer status (toner level and so on), etc. Also these systems are capable of doing topology discovery based on CDP, LLDP, routing tables.