Troubleshooting device capture issues

If you encounter errors when performing a device capture, use the steps described in this section to either resolve the issue or have the required information ready to create a BMC Support case.

Issue symptoms

Occasionally, errors occur when performing a device capture. The errors are listed in the following two files that are part of the .zip file generated during device capture. 

• capture.log – This file contains the sysObjectID and sysDescr values. You can examine this file and confirm if the device capture is complete or if there are any error messages.
• <ip_address>@public.MVC – This file contains the formatted device dump. 

Scope

This issue impacts all versions of BMC Discovery.

Resolution

This section lists specific issues that can occur during a device capture and provides resolution steps that you must perform in each case. For information about performing a device capture, or requesting BMC Support to enable the integration for an unsupported SNMP device, see the BMC Community article,  KA 000349819 .

Issue: A device capture fails with the message, ERROR: SNMP++: SNMP request timeout or Device skipped - no SNMP access

The following screenshot shows a failed device capture:

You can get information about a device capture from the DiscoveryAccess page and the Device Info page. For more information about device capture, see Capturing SNMP devices.

In some cases, performing a capture from a Device Info node may result in a blank screen. If you click the browser's Back button, it returns to the Device Info page and briefly displays a banner with the message, Device skipped(no SNMP access), as shown in the following screenshot. 

Resolution

There are several possible reasons for this problem. To investigate the causes and resolve the issue, perform any of the following steps relevant to your setup: 

• Confirm that an SNMP credential is present and that the IP range includes the address being discovered. A valid credential is needed for device capture.
• Run a credential test and examine the result.
• Increase the timeout in the SNMP credential to 100 seconds and retry.
• Find out the SNMP version of the credential. For example, find out if it is version v1, v2c, or v3. Investigate if the device is configured to respond on that SNMP version.
• If the device supports SNMP versions other than the one specified in the credential, change the version in the credential and retry.
• For SNMP v1 and v2c, make sure that the community string in the SNMP credential is correct. An invalid community string can cause an error, Unable to get the deviceInfo:TRANSIENT.
• Get the following information from the device administrator:
  • If there is an Access Control List (ACL) or another configuration on the device that prevents responses to the BMC Discovery appliance.
  • If the device is configured to use the default SNMP port 161. Run nmap to confirm that the port is open. (The command to run nmap is described in the following step 1).
• On the DiscoveryAccess page, click the link titled script failure or <xxx> Session Results related to look for clues.
• In case of a timeout during a device capture, check the log in the directory /usr/tideway/var/captures for additional clues.
• In case of a timeout during a scan, turn the DEBUG logging on for BMC Discovery, run the scan again, and check the file tw_svc_discovery.log for clues. Later, remember to turn the DEBUG logging off.
• Confirm that the IP range is correct. If the IP range is incorrect, rectify the IP range and mask on the device.
• In another user environment where they were using SNMP v3, the user found that reducing the length of the Privacy Key from 33 characters to 18 characters resolved the credential test failure. The discovery scan too started working. You can try a similar update to the Privacy Key length.
• From the BMC Discovery command line, log in as the user tideway, and perform the following steps:

  1. Run the following commands:

     1. Check the connectivity from the appliance to the endpoint:

        /usr/bin/nmap --privileged -sT -sU -p T:22,U:161 [device_ip_address]

     2. Check the connectivity from the Outpost command prompt to the endpoint:

        C:\Program Files\BMC Software\Discovery Outpost\nmap --privileged -sT -sU -p T:22,U:161 [device_ip_address]

        The expected result is that port 161 must have a state of open or open|filtered, as shown in the following screenshot:

        

  2. Run the snmpWalk command to the device from the appliance as the tideway user:

     • SNMP v1:

       /usr/tideway/snmp++/bin/snmpWalk [device_ip_address] -v1 -Cpublic

     • SNMP v2:

       /usr/tideway/snmp++/bin/snmpWalk [device_ip_address] -v2c -Cpublic

     • SNMP v3:

       /usr/tideway/snmp++/bin/snmpWalk [device_ip_address] '1.3.6.1.2.1.17.4.3.1' -v3 -snMyLogin -sl2 -authMD5 -uaMyPassword
       /usr/tideway/snmp++/bin/snmpWalk [device_ip_address] '1.3.6.1.2.1.17.4.3.1' -v3 -snMyLogin -sl3 -authSHA -ua'My$Password' -privDES -up'MyPrivateKey'

     • Redirect the Outpost to a file. For example:

       /usr/tideway/snmp++/bin/snmpWalk [device_ip_address] -v2c -Cpublic >> /tmp/snmpWalk.out

• Additionally, you can try the following steps:
  • Change the SNMP version and community string, as needed. 
  • If you are using SNMP v3, specify the other parameters for it. 
  • To see the usage notes with a list of available options, run snmpWalk with the --help option.
  • You can install snmpWalk for Windows on the Outpost and run it from the command prompt. One of the download sites for snmpWalk is https://ezfive.com/snmpsoft-tools.

If the snmpWalk command fails and the earlier instructions also fail to provide a solution, discuss with the device administrator or contact BMC Support and provide them with the results of the checks you performed earlier.

Issue: A device capture fails with the message, ERROR: sysObjectID is not an enterprise MIB

In this case, the following error message is displayed during a failed device capture: 

sysDescr: Cisco Secure Access Control System 5.4

sysObjectID: 1.3.6.1.2.1.47.1.1.1.1.13.1

ERROR: sysObjectID is not an enterprise MIB: 1.3.6.1.2.1.47.1.1.1.1.13.1

Resolution

BMC Discovery expects every sysObjectID to begin with the value 1.3.6.1.4.1 as per the SNMP MIB standard. Each vendor is allocated a subtree under 1.3.6.1.4.1. In this case, because the sysObjectID does not comply with the SNMP MIB RFC published at rfc3418.txt , it is currently not possible to discover this device.

Issue: A device capture fails with the message, ERROR: Loop detected

In this case, the following error message is displayed during a failed device capture: 

Dumping range: Start of MIB to End of MIB

ERROR: Loop detected: current OID is 1.3.6.1.2.1.17.4.3.1.1.0.0.170.199.13.135, 
WAS 1.3.6.1.2.1.17.4.3.1.1.44.65.56.156.227.187 previous OID, 
OID ILD is 1.3.6.1.2.1.17.4.3.1.1.44.65.56.156.227.187

When you run the snmpWalk command, the following output is displayed:

SNMP++ snmpWalk to <ip address> SNMPV2 Retries=1 Timeout=1000ms Community=<community>

[...]

1.3.6.1.2.1.1.9.1.4.1 = 0:00:00.00

1.3.6.1.2.1.2.1.0 = 31

1.3.6.1.2.1.2.2.1.1.1 = 1

1.3.6.1.2.1.2.2.1.1.1 = 1

1.3.6.1.2.1.2.2.1.1.1 = 1

[...]

Resolution

In this case, the "next OID" of 1.3.6.1.2.1.2.2.1.1.1 points to itself. This is not normal and it indicates a loop. In some cases, it may be possible to work around this issue. Contact BMC Support and provide them with the device capture file.

Issue: A device capture for a router device takes hours to complete

If a router device has a huge routing table, a device capture may either take a long time to complete or fail after attempting to capture for a long time.

Resolution

If the device capture is not completed even after several hours, you can cancel it and share the partial capture details with BMC Support for device integration. In some cases, the partial device capture contains sufficient information to have a successful device integration.

Issue: A device capture fails with the message, ERROR: SNMP: Variable does not exist

This case indicates a problem with the device or the SNMP agent running on it. To confirm if this is the problem, run the snmpWalk command on the device.

Resolution

If the snmpWalk command fails or does not produce usable output, contact the device vendor.  

Issue: A device capture fails with the message, ERROR: SNMP: Cannot perform operation, General Error

This case indicates a problem with the device or the SNMP agent running on it. To confirm if this is the problem, run the snmpWalk command on the device.

Resolution

If the snmpWalk command fails or does not produce usable output, contact the device vendor. In some cases, the device capture may produce a partial capture file that is sufficient to integrate the device. If you observe that this is the case then contact BMC Support, and provide them with the device capture file and the snmpWalk output.