L2 Topology not updating

[gmonk63]

current version is 4.1.377  We have a layer2 redundant loop in our network and needed to break the loop by shutting down one of the switch interfaces temporarily. However netxms never updates the topology to reflect the broken loop even after two days its still shows the link connected between the two switches when interface details on both switches shows the interface as down.  I would expect the link to be removed after a topology poll was completed showing the loop broken in the middle where the interfaces are down. Is this normal or do I have to do something to force an update.

Thanks

[victor]

When interface is down, we have two contradicting requirements: one is to show what was connected to that interface before it went down, and other is to show actual connectivity. First requires to keep showing link between disconnected interfaces, second requires to delete that link immediately after interface goes down. As NetXMS server has no way of knowing if disconnect is permanent or temporary, and there are seems to be more requests to provide access to last known connection information, NetXMS server keeps that connection until it will know that topology was changed (for example, one of previously connected interfaces will go up and LLDP will report different peer).
One possible solution could be configurable topology expiration time - i.e. if interface is down for N days, remove any known topology information from it.
Currently as a workaround you can delete interface that is disconnected - configuration poll will find it and re-create, but peer information will be erased.

Best regards,
Victor