21.24 Suppressing the use of discovery protocols for specific nodes
NNMi uses several protocols to discover Layer 2 connectivity between and among network devices. There are many defined discovery protocols; for example, Link Layer Discovery Protocol (LLDP) is an industry standard protocol. There are also many vendor-specific protocols, such as Cisco Discovery Protocol (CDP) for Cisco devices.
You can configure NNMi to suppress discovery protocol collections for devices you specify. There are special circumstances, such as those described below, which might be remedied by suppressing discovery protocol collections.
- Enterasys devices:
Using SNMP to collect information from the Enterasys Discovery Protocol (EnDP) and LLDP tables on some Enterasys devices might cause issues with NNMi running out of memory. You can prevent this by configuring NNMi to skip EnDP and LLDP processing on these devices. To do this, add the management addresses of the devices to the disco.SkipXdpProcessing file. For details, see 21.24.1 Suppressing the use of discovery protocol collections.
New operating system versions on some Enterasys devices support the set snmp timefilter break command. On such Enterasys devices, run the set snmp timefilter break command. When you use this command to configure such a device, you do not need to list the device in the disco.SkipXdpProcessing file.
- Nortel devices:
Many Nortel devices use the SynOptics Network Management Protocol (SONMP) to discover Layer 2 layout and connectivity. Some of these devices use the same MAC address on multiple interfaces, which does not work well with this protocol. You might experience this problem if two interconnected Nortel devices show a Layer 2 connection between the wrong set of interfaces and the connection shows a connection source of SONMP.
For this example, it is best to configure NNMi to not use the SONMP protocol to derive Layer 2 connections for the devices shown as participating in the wrong connection. To do this, add the management address of the two devices to the disco.SkipXdpProcessing file. For details, see 21.24.1 Suppressing the use of discovery protocol collections.
- Organization of this section