TheSonicGod
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Intermittent DNS Errors - bounce backs received on emails
Hi Everyone:
We are experiencing intermittent errors (very frustrating) with email that seemed to have started yesterday.
Emails being sent to domain cipherpharma.com fail intermittently showing up as DNS errors. It works and then it doesn't work.
Error received is as follows:
Sorry, I couldn't find any host named cipherpharma.com. (#5.1.2)
The nameservers are with Netfirms (ns1.netfirms.com and ns2.netfirms.com) and nothing has changed on the settings in several years.
I have contacted Netfirms to see if any issues on their end, and of course, they indicated that their dns servers are fine.
Having said this, when I check the domain on mxtoolbox.com it shows the correct DNS entries but if I refresh the tool, every so often I get an error that shows: "No records exist" when reporting from ns2.netfirms.com (ns1.netfirms.com always show the correct dns records).
I'm not sure where to go from here. Netfirms (after 5 or so calls to them) says nothing is wrong on their end.
What other tools would you suggest I use to diagnose this?
Or what would your next step be?
I'm hoping someone out there can help as I've been on this since last night and am running out of ideas, short of moving the domain to a different registrar and name servers; however, that is my last resort!
Thanks for your feedback.
Ron
We are experiencing intermittent errors (very frustrating) with email that seemed to have started yesterday.
Emails being sent to domain cipherpharma.com fail intermittently showing up as DNS errors. It works and then it doesn't work.
Error received is as follows:
Sorry, I couldn't find any host named cipherpharma.com. (#5.1.2)
The nameservers are with Netfirms (ns1.netfirms.com and ns2.netfirms.com) and nothing has changed on the settings in several years.
I have contacted Netfirms to see if any issues on their end, and of course, they indicated that their dns servers are fine.
Having said this, when I check the domain on mxtoolbox.com it shows the correct DNS entries but if I refresh the tool, every so often I get an error that shows: "No records exist" when reporting from ns2.netfirms.com (ns1.netfirms.com always show the correct dns records).
I'm not sure where to go from here. Netfirms (after 5 or so calls to them) says nothing is wrong on their end.
What other tools would you suggest I use to diagnose this?
Or what would your next step be?
I'm hoping someone out there can help as I've been on this since last night and am running out of ideas, short of moving the domain to a different registrar and name servers; however, that is my last resort!
Thanks for your feedback.
Ron
ASKER
Hi Will,
Thanks for your reply. We have a PTR record 64.40.243.3 pointing to mail.cipherpharma.com
I suspect it may be one of the nameservers (ns2.netfirms.com) causing issues but I can't seem to prove it to Netfirms.
Any other suggestions?
Ron
Thanks for your reply. We have a PTR record 64.40.243.3 pointing to mail.cipherpharma.com
I suspect it may be one of the nameservers (ns2.netfirms.com) causing issues but I can't seem to prove it to Netfirms.
Any other suggestions?
Ron
What is the exact error message you are getting on the bounce back emails?
Also have you checked the email headers as well for more info?
Will.
Also have you checked the email headers as well for more info?
Will.
Hi,
Does your exchange server uses ns2.netfirms.com for External DNS lookup ? , if so for testing purpose you can use google puble ip address 8.8.8.8 , 8.8.4.4 for external DNS lookup and check for issues.
after changing public ip if everything is fine then it may be one of the nameservers (ns2.netfirms.com) causing issues .
External DNS Lookup setting is available on Hub Transport Server Properties.
Also make sure "Use the External DNS Lookup settings on the transport server " is checked on Hub transport properties.
Does your exchange server uses ns2.netfirms.com for External DNS lookup ? , if so for testing purpose you can use google puble ip address 8.8.8.8 , 8.8.4.4 for external DNS lookup and check for issues.
after changing public ip if everything is fine then it may be one of the nameservers (ns2.netfirms.com) causing issues .
External DNS Lookup setting is available on Hub Transport Server Properties.
Also make sure "Use the External DNS Lookup settings on the transport server " is checked on Hub transport properties.
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I would start their first.
Will.