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smtp roundtrip problem




I've setup an snmp/pop3 round-trip sensor. The sensors sends email through the a local mail server to a Gmail mailbox.

Recently I have been getting this error message at random times: "Connecting to POP3 Server: service exception: DNS error"

The problem resolves itself before comming back again.

Any idea for the cause? Also, the pop3 response time is always this high? 300,000ms and more..


pop3 roundtrip smtp

Created on Dec 26, 2013 9:03:49 AM

2 Replies



What settings are you using for the sensor? Have you tried resolving the name in the command line to see how long that takes? You also might want to try for testing setting the server up with custom DNS server settings and see if that makes a difference.

Created on Dec 26, 2013 2:51:05 PM by  Greg Campion [Paessler Support]



Thanks for your replay. Ended up being ipv6 resolving.


Created on Dec 31, 2013 6:17:21 AM

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