SNMP
vScope can inventory a wide range of network assets using SNMP, such as printers, switches, and routers. Ensure the correct credentials and IP range access settings are in place to enable successful discovery.
Requirements for SNMP Discovery
Section titled “Requirements for SNMP Discovery”- Credential: Provide the appropriate credential for the SNMP version (v1, v2c, or v3).
- Network Access: The vScope server must have access to the network IP range for SNMP queries.
- SNMP Ports: Typically uses UDP port 161 for standard SNMP and UDP port 10161 for secure SNMPv3.
Configuring SNMP Versions
Section titled “Configuring SNMP Versions”SNMP v1 & v2c
Section titled “SNMP v1 & v2c”For SNMP versions 1 and 2c, you only need to enter the community string for devices in the SNMP credential. Commonly, this is set to "public" in lowercase by default. Then, specify the IP ranges where these devices are located.
SNMP v3
Section titled “SNMP v3”SNMP version 3 requires additional credentials due to enhanced security. Enter all necessary details and configure the target IP ranges for devices using SNMPv3.
Collecting Custom OIDs
Section titled “Collecting Custom OIDs”By using Tags from Discovery, you can collect custom values from OIDs on network devices and add them as tags in vScope.
Steps to Add Custom OIDs
Section titled “Steps to Add Custom OIDs”-
Open SNMP Credential Settings
Go to the Advanced section of your SNMP credential configuration. -
Input Extra OIDs
Enter the specific OIDs you wish to collect from your network devices. Separate multiple OIDs with commas. -
Save the Credential
Save the changes. During the next discovery scan, vScope will automatically pull data from the specified OIDs and walk down the Management Information Base (MIB) tree from those points. -
Run a Discovery
Start a Discovery with the updated SNMP credential settings. -
Configure Tags from Discovery
Once the discovery scan completes, go to Tags > Tags from Discovery to manage the collected values. Configure the tags as desired for improved visibility in vScope. -
Run Another Discovery
Initiate another discovery to apply the new tag configuration to all SNMP devices of the same model.
You can now access your custom OID values within vScope, making it easier to track and analyze specific attributes of SNMP-managed assets.
Switch Port Mapping Requirements (CDP/LLDP)
Section titled “Switch Port Mapping Requirements (CDP/LLDP)”vScope can map switch ports to connected devices using SNMP by leveraging industry-standard neighbor discovery protocols: LLDP (Link Layer Discovery Protocol) and CDP (Cisco Discovery Protocol).
To enable accurate switch port-to-device correlation, ensure the following requirements are met.
General Requirements
Section titled “General Requirements”-
Neighbor Discovery Enabled
Either LLDP or CDP must be enabled both on the switch being scanned and on the remote device connected to one of its ports. -
SNMP Access
The SNMP credential used for discovery must have permission to read the LLDP or CDP tables / branches listed below. -
Network Access
The vScope server must be able to reach the switch via SNMP. To allow vScope to match a switch port with its connected device, both ends of the connection must be inventoried.
LLDP Requirements
Section titled “LLDP Requirements”If LLDP is used, vScope requires access to specific LLDP MIB branches. If these branches are not present on the device, it will not be possible to model the relationship.
| Description | Required SNMP Table / Branch |
|---|---|
| LLDP Local System & Port Information | lldpLocalSystemData 1.0.8802.1.1.2.1.3 |
| LLDP Remote System Information | lldpRemoteSystemsData 1.0.8802.1.1.2.1.4 |
CDP Requirements
Section titled “CDP Requirements”If CDP is used instead, vScope requires access to the following CDP branches:
| Description | Required SNMP Table / Branch |
|---|---|
| CDP Interface Information | cdpInterfaceTable 1.3.6.1.4.1.9.9.23.1.1.1 |
| CDP Neighbor (Cache) Information | cdpCacheTable 1.3.6.1.4.1.9.9.23.1.2.1 |
| CDP Global Device Information | cdpGlobal 1.3.6.1.4.1.9.9.23.1.3 |
Additional Resources
Section titled “Additional Resources”Common Errors
Section titled “Common Errors”| Error | What happened? | Suggested action |
|---|---|---|
| No response: Connection timed out | The SNMP credential was unable to connect to the target. | Make sure that the correct SNMP version and port are being used for the target. |
| Target did not respond. It might be down or access is denied | Generic error for failed discovery. | Common errors: Device not responding or Invalid credentials. |
| Device is not found | Most likely due to the absence of a globally unique MAC address for vScope to uniquely identify the asset. | Ensure that the asset has a globally unique MAC address assigned. |
| Device is found, but added as All Machine | Caused by the missing MIB module for printer management. | Install or load the MIB module for printer management. |
| Device is found, but is missing information | Due to a mismatch of the expected OID structure. | Use Custom OID to add more OIDs to vScope’s inventory or submit a feature request to the support team to improve SNMP discovery. |
Debugging
Section titled “Debugging”To help us to better understand the issue, we recommend running a SNMP test using Paessler’s SNMP Tester Tool.
- Run the SNMP Tester, target the missing devices(es).
- Share the results with support@infrasightlabs.com.