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NBX goes offline from E resolvQuery 6b0002 error

Boris L. Perlovsky
Occasional Advisor

NBX goes offline from E resolvQuery 6b0002 error

Hello - I'm hoping someone can help me out.  I have an NBX V5000 (SS3) with Offsite Notification enabled.  Recently my NBX went down - stopped responding to ping and all phones were down.  I checked the logs and just before it went down there was this error:  E resolvQuery on sampledomain.com returned: 6b0002.  

I've replaced the actual domain that was listed with "sampledomain.com".  I've seen this happen before, albiet not recently.  Has anyone else experienced this?  Any suggestions for a fix?  

Thanks much!



Super Advisor

Re: NBX goes offline from E resolvQuery 6b0002 error

what version of code ?

How many tels ( ballpark ) ?

As far as I know , this should not occur . Although it could due to maybe  a bad domain name .

Older codes had issues , but R6.0 or R6.5 I have not heard anything


Boris L. Perlovsky
Occasional Advisor

Re: NBX goes offline from E resolvQuery 6b0002 error

Code version is 5.0.28.

Total devices - about 1000.

The domain is not bad, as I tested it immediately afterward by sending a direct email that went through.

I'm not looking forward to upgrading, and my understanding was 5.0.28 was supposed to be super stable.

Any other thoughts?

Super Advisor

Re: NBX goes offline from E resolvQuery 6b0002 error

Well , 5.0.28 is an older version , as we are now up to R6.5.22 Patch 3 ( a couple of years sionce this was released ! ) . At the minimum there is a 5.0.31 code . Not sure how the system went down , power fail , bug , etc . I would try to do the upgrade only due to maybe something in the code got messed up when the site went down.

1. Reboot to R5.0.31

2. USe cfg log and enable nbxintenot0 and see what the NBX is sending for SMTP traffic .


Super Advisor

Re: NBX goes offline from E resolvQuery 6b0002 error

This has been a very popular solution for maby years . as telephone guys we are not really dns / exchange savy . This is a great doc to assist in troubleshooting osn issues . Those errors , 6bXXXX can be found in a network trace with DNS descriptions instead of hex .

example 6b0003 is a domain name error failure . Use the network  trace for a better description and troubleshooting .

The following is a Primus(R) eServer solution:

ID: 3KB12262

Domain: primus_owner

Solution Class: 3KB51

Problem    Voicemail ports lockup and system crashing

Problem    Offsite email notification not delivering to one or all email domains

Problem    Email Notification unable to send email to customers own domain email only - others OK

Problem    Voicemail ports hang up

Problem    Netset not responding

Fact       No tasks suspended on CLI

Fact       SuperStack 3 NBX

Fact       NBX 100

Fact       NetSet

Fact       NBX Voicemail

Fact       Offsite Notify

Cause      DNS server not properly responding with MX record detail for email notifications, which causing vm ports to lockup and system to crash.


 Some customer-provided DNS servers (internal DNS servers) my not be configured to respond in a way the NBX expects for MX record queries, resulting in these symptoms for some customers.     

 NOTE: Microsoft recently (October 2008) changed the way their DNS software responds to query for security reasons, and this may affect existing NBX customers who have their own internal DNS and mail server.  If you are an existing NBX customer who had email notification working to your own internal email server using your own DNS server, and email notifications suddenly do not get sent to your email users, but the NBX can still send email to other email domains, you have likely been affected by the recent Microsoft change. We recommend you skip to the bottom and use an external DNS server with  a NAT translation in your router.

 Follow these simple steps to confirm if your DNS server is properly responding to the NBX:

 Premise.  User has notification set to send email notification to misterbig@cox.netmailto:misterbig@cox.net">misterbig@cox.net>

   Make sure your PC is configured to use the same DNS server IP as is set in NetSet system settings

  From your PC at the DOS prompt type  the following to elicit a DNS server response.  You type the text in bold print (nslookup, set type=mx, and cox.net)


Default Server:  mboqip2.ne.3com.com


 > set t...


This message was edited by merlin on 8-31-10 @ 7:42 AM