I am unable to discover interfaces of type 'other' or loopback.

Document ID : KB000031742
Last Modified Date : 14/02/2018
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Problem: When trying to discover devices, interfaces of type other and looback are not being discovered.

Cause: By default discovery of other and loopback(24) interfaces are disabled. You can enable them for CA Performance Management 2.5 or above versions.

Environment: CA Performance Management 2.5 and above 

Resolution: The extension ability can be used in the typecatalog to extend the OOTB vendor certifications for the various OOTB interface vendor certifications.

Here is an example of what extension looks like for OOTB Interface vendor certification:

<?xml version="1.0" encoding="UTF-8"?>
<DataModel namespace="http://im.ca.com/certifications/snmp" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="SNMPCertificationFacet.xsd">
  <FacetType name="IfTableMib" descriptorClass="com.ca.im.core.datamodel.certs.CertificationFacetDescriptorImpl">
    <FacetOf namespace="http://im.ca.com/core" name="Item" />
      <ExpressionGroup destCert="{http://im.ca.com/normalizer}NormalizedPortInfo" name="PortNRMDS">
        <Expression destAttr="Type">ifType</Expression>
Note: The XSD requires an Expression (or one of the other 2 options) in an ExpressionGroup, the ifType expression has been provided again even though it did not change from OOTB.
  1. Go to http://<da>:8581/typecatalog/certifications/snmp/<VC Name>
  2. Copy the Expressions, ExpressionGroup, and Filter lines to a new file for later use.  Find the Expression line for ifType and copy that line also.  Example:
    a. <Expressions>
    b.  <ExpressionGroup destCert="{http://im.ca.com/normalizer}NormalizedPortInfo" name="PortNRMDS">
    c.    <Filter>(ifType!=24) && (ifType!=1)</Filter>
    d.    <Expression destAttr="Type">ifType</Expression>
  3. Do a REST GET of http://<da>:8581/typecatalog/certifications/snmp/extension/<VC Name>
  4. Copy the contents into your REST client's body.
  5. Increase the Version value.
  6. Take the Expressions, ExpressionGroup, Filter, and Expression lines previously saved off and place after FacetOf line.  See final example above.
  7. Change the Filter to only:  <Filter>(ifType!=24)</Filter>
  8. Add after Expression line, the closing </ExpressionGroup> and </Expressions> lines.
  9. Send the contents via REST PUT to http://<da>:8581/typecatalog/certifications/snmp/extension/<VC Name>
  10. Do a REST GET to http://<da>:8581/typecatalog/certifications/snmp/extension/<VC Name> to confirm your changes are there.
  11. During next change detection, it will discover the 'other' interfaces.

Additional Information: If you wish to remove the (ifType!=24) to discover loopback addresses, we have seen CAPC consolidation issues if devices that have a primary or seconday IP address of  So if you wish to discover loopback interfaces, you should use a filter to not discover interfaces with as an IP address.