This document outlines the options for "Discover Connections" in CA Spectrum for device models that have already been created in the CA Spectrum Database. Original connections were done with Autodiscovery. How can we make sure they stay current?
Component: SPCDIS - Discover Connections.
There are four ways to launch/update discover connections in the topology view of CA Spectrum:
1. MANUALLY launch the discovery from the Discovery Gui. When you select the “Discover and automatically model to SPECTRUM” option and then manually press the Discover button in the lower right hand corner, this will trigger the rediscover connectivity functionality.
Note: Scheduling CA Spectrum's discovery in 9.2.x and 9.3.x does not update device model connectivity within CA Spectrum. You must use one of these four options outlined
2. From the device, when you right click the model, in Reconfiguration area, you can press the Discover Connections button.
3. From the device, in the Component Detail -> Information Tab -> Reconfiguration area, you can set the device to Discover Connections After Link Up Events to True
4. From the device, in the Component Detail -> Information Tab -> Reconfiguration area, you can set the Discovery after Reconfigure option to True.
In CA Spectrum version 9.4 and above, you have the options above, PLUS a new feature added:
You can schedule a discovery to run and select the new option of “Discover Connections During Scheduled Discovery”:
When you schedule the discovery and you select/enable the “Discover Connections During Scheduled Discovery”, CA Spectrum will rediscover the connections for the models that are contained within that discovery. If you do not select this option when scheduling a discovery, CA Spectrum will only create new connections for newly created models. Any models that are discovered that are already modeled will not have their connectivity updated. Also, when you select this option, CA Spectrum will recreate previously destroyed models (as long as it meets the criteria of the discovery). For example if you destroyed a device with IP 172.19.10.10 and then you schedule the discovery to cover that IP and you have Discover Connections During Scheduled Discovery option selected, it will recreate the model (assuming it responds to SNMP/ICMP).
NOTE: CA Spectrum discovery will not always remove old/stale connections unless the connection has been updated on an interface that had a previous connection. For example, if you have a connection on Fa0 <->Fa0 and you change it to Fa1<->Fa1, Spectrum will create the new connection on Fa1<->Fa1 and will leave the old Fa0<->Fa0 connection there (even if you use the Discover Connections During Scheduled Discovery option). If you updated the connection from Fa0<->Fa0 to Fa0<->Fa1, then Spectrum WILL destroy the connection and create the Fa0<->Fa1 connection. It will not leave the old Fa0<->Fa0 connection.
The reason for this is that Spectrum doesn't always know if the connection is really old/obsolete or not. When a physical connection is broken, the layer 2 connection info in the MIB table would be gone, but we don’t want to remove the pipe in Spectrum as it could just be down. Instead Spectrum will generate an alarm for the broken connection.
Please take note that enabling the above options (Discovery after Reconfigure and/or Discover Connections After Link Up Events) can be VERY expensive and most likely will add to resource utilization by the SpectroSERVER.
The best option/best practice for updating connectivity between device models that are already created is to use the scheduled discovery with the "Discover Connections During Scheduled Discovery" option selected (that option is only available in Spectrum 9.4 and above). You can schedule the discovery to run during an off peak time, and have it rediscover the connectivity at that time.