17 Replies Latest reply on Apr 12, 2016 8:00 AM by lynchnigel

    Network Atlas - Link Status Issue

    nathan.miller@gwfathom.com

      OK - perhaps I have failed in my search attempts.  If this is the case and the "right answer" is "RTFM - look here" I'll apologize for the search fail - and will be grateful for the pointer.  That said - I've not found much in the way of documentation for Network Atlas and I am struggling to understand how link status is determined.  In short, I have a number of links / connections that show as "down" despite the fact that I know they are up.  It appears that a common factor in the links with this condition is a lack of a CDP relationship between the devices.  In one case the interfaces between our firewalls' inside interfaces and the corresponding switch interface (L2 connectivity) shows down despite both interfaces being up and passing traffic.  The firewalls are not CDP participants.  In the other case, links between a couple of HP Procurve switches are shown as down.

       

      In both case sets I have done the following:

      • physical cross connect between the devices has been verified  In each case there is NOTHING between the two devices except a single ethernet patch cable.
      • mac address tables on both devices show the other device as the peer device on the port in question.
      • traffic is flowing on the link between the devices
      • the Network Atlas link has been opened (right click > properties) and the the generic related interfaces have been applied (drag and drop from the managed node in the list)
      • When viewing the related interfaces in Network Atlas Link Properties they show "Status:Object status is Up"
      • The same configuration / configuration approach has been applied to other linked interfaces and where the two devices are both CDP enabled life is good and the links show up/down condition properly

       

      So - Network Atlas is using SOMETHING other than the relationship that I establish between the interface objects that I establish in the map, and the related link status, to determine the health of the link.  I can not find documentation that tells me how this determination is being made - and more importantly how I can build a map that accurately reflects the condition of my environment without CDP between these devices. 

       

      Thanks in advance...