currently are u able to ping device B from zenoss?

when you add device B to zenoss, it should have discovered that to get to B, you go thru A and this will be indicated in the "Routes" component of the OS tab.

zPingMonitor is True by default for added devices, so if device B goes down, you will receive an alert to say device B is down, you dont need to do anything in this case.

however if the route to B is not in routes, thats when you can have a situation where both A and B alert as down when only A goes down.

if you cant ping device B, it means icmp is blocked along the way (possibly by the router) so you need to modify ACLs on the router to allow icmp both ways.

Like i said, You can only reach B when A is up. so when B goes down (when A is up) the ping monitor will notice this and will generate a device down event. Now if you want to receive that alert, you put an alert rule for the specifi user who should receive the alert, with:

Event State = New

Severity >= Error

To receive alert when B goes down (when A is up)

      Do as I described above

To AVOID or SUPRESS (not to receive)   alerts when B goes down (and A is down)

      Use an event transform which implements dependency for example:

if device.id == 'device_B':
    device_A = device.findDevice('id_of_device_A')
    if device_A.getPingStatus() > 0:
        evt.eventState = 2 # suppress or substitute this with line below to drop it
        evt.action = "drop"

This supresses all events for device B when device A is down.

I know this is an old post but this code no longer works with Zenoss 4.2.

Problem with line 2: if device.id ==

Anyone know what it needs to be now?