not listening on tcp

[Thomas Schulz]

In article <d6q1v8$2as$1 at sf1.isc.org>, Maria Iano  <maria at iano.org> wrote:
>I ran netstat -a and saw that nothing was listening to port 53 at the 
>time. Then I restarted Bind and saw that tcp 53 was being listened to, 
>and tcp DNS queries were answered. Then I restarted Bind and netstat -a 
>showed tcp port 53 was not being listened to, and tcp DNS queries were 
>not answered, and then I restarted Bind and tcp port 53 was being 
>listened to and tcp DNS queries were answered, and so on...  It 
>appeared to be alternating, but I only restarted it about 7 times so 
>that could easily just be coincidence.

I assume that a restart is just a stop followed by a start.  Perhaps the
old process has not quite let go of the tcp port when the new one is
starting.  Try putting a 'sleep 1' between the stop and the start.
Better yet, don't restart bind.  See if a 'rndc reload' will do what
you need.

>
>Thanks,
>Maria
>
>On May 21, 2005, at 2:02 AM, Barry Margolin wrote:
>
>> In article <d6lede$2m3k$1 at sf1.isc.org>, Maria Iano <maria at iano.org>
>> wrote:
>>
>>> I recently upgraded to Bind 9.3.1 on some servers running Red Hat 
>>> Linux
>>> release 8.0 (Psyche). A few days later, one of the servers suddnly 
>>> stopped
>>> listening to tcp port 53 on one of its interfaces. It continued 
>>> listening to
>>> udp port 53. I have found that when I restart Bind on these servers,
>>> sometimes it starts listening on both tcp and udp on all interfaces 
>>> as it
>>> should, and sometimes on one of the interfaces it listens on only 
>>> udp. The
>>> loopback interface never seems to have a problem, but always seems to 
>>> listen
>>> on both tcp and udp. It is only the non-loopback interfaces that have 
>>> this
>>> problem. I haven't tested this by restarting Bind more than about 10 
>>> times,
>>> but it seems to be that it alternates.
>>>
>>> Has anyone else seen anything like this?
>>>
>>> Thanks,
>>> Maria
>>
>> Could there be some other process listening on TCP port 53?  What does
>> lsof say when BIND fails?  Is there anything in the log when this
>> happens?
>>
>> -- 
>> Barry Margolin, barmar at alum.mit.edu
>> Arlington, MA
>> *** PLEASE post questions in newsgroups, not directly to me ***
>>
>>
>
>


-- 
Tom Schulz
schulz at adi.com