When a device contains multiple network adapters that use the same MAC address and IP address, the identifier cannot discriminate each adapter and throws an error to avoid creating duplicate CIs in the CMDB. This error stops Discovery at the identification phase, without creating or updating any CIs.

Steps to Reproduce

Discover a device with multiple adapters with the same MAC address and IP address. For example, discover a software load balancer that uses the same mctap (macvtap) interface whose MAC mirrors one of the ethernet interfaces.

This results in an error similar to this:

 2019-04-26 15:48:55 : Error : identification_engine : DUPLICATE_LOOKUP_PAYLOAD Found duplicate Lookup items (7 and 12) in the payload index 0 using fields ip_address,mac_address



    1. Navigate to Discovery Definition > CI Identification > Identifiers.

    2. Open the Hardware Rule record.

    3. In the Identifier Entries related list, add "name" to the criterion attributes on the Network Adapter [cmdb_ci_network_adapter] table.

    4. Save the record.

    5. Navigate to System Definition > Script Includes.

    6. Add "name" to the following line in the DiscoveryJSONIDSensor and DiscoveryIDSensor script includes:

      From: this.ciData.convertRelatedList(this, 'cmdb_ci_network_adapter', 'cmdb_ci', 'mac_address,ip_address');

      To: this.ciData.convertRelatedList(this, 'cmdb_ci_network_adapter', 'cmdb_ci', 'mac_address,name');

    7. Save the records.



Related Problem: PRB1342084

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Intended Fix Version


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Article Information

Last Updated:2019-07-18 12:08:43