Dynamic IP address and a possible problem/bug

Hi All,

I have few nodes polled as Dynamic IP for reasons that I will not discuss here.

Today we saw that a node (host_A) that was down during last days, is back up again for Orion even if the actual server is still down. The fact is, Orion is now pinging a different server (host_B), with a different name, that has taken the "last IP" used by host_A when it was available.

It seems to me that this has happened because the host_A is no more present in the DNS, and the only thing left for orion look for is the IP. This is a problem, because dynamic IP nodes that are actually down (so down that they've been removed from the dns) may be wrongly reported as UP!

Is this a known behavior?

Thanks.

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rob.hock

Dave,

This behavior would be expected at present. The results of the last A record lookup for that host are stored in the DB. In the event DNS lookup fails, NPM is still able to poll the device via last-known IP for that host. To test for DNS lookup failure- SAM has a built in DNS user experience template.

akhasheni

This behavior would be expected at present. The results of the last A record lookup for that host are stored in the DB. In the event DNS lookup fails, NPM is still able to poll the device via last-known IP for that host. To test for DNS lookup failure- SAM has a built in DNS user experience template.

Rob: sorry but it's the other way around. The expected behavior for NPM would be to use DNS and not to cover for it. DNS is not NPM's job, it's to treat DDNS as such.