nodata()

[getUP]

We have a trigger which we hoped was able to give us some information when the agent stopped responding.

The expression we use is as follows:
{Template:agent.ping.nodata(60)}=1

We're not receiving any notifications though. Is there anything we're doing wrong with this trigger?

[Bill Wang]

We have a trigger which we hoped was able to give us some information when the agent stopped responding.

The expression we use is as follows:
{Template:agent.ping.nodata(60)}=1

We're not receiving any notifications though. Is there anything we're doing wrong with this trigger?

I met some alike issues, that I've always noticed sometimes the value of a trigger is "UNKNOWN", and I don't know why, it returned to normal later.