[BlueOnyx:13505] Re: EMail clogging up - DNS?

[Gerald Waugh]

On 08/09/2013 11:22 AM, Jim Matysek wrote:
> We've had this happen every now and then, particularly during heavy 
> usage times on the server.
>
> Running 5106R on an Aventurin{e} VPS. What happens is that email sent to 
> our hosted domains gets stuck in /var/spool/mqueue and not delivered. We 
> can get thousands of messages stuck there in the course of several 
> hours. When I shell into the machine and try an nslookup usms.org (our 
> main domain), I get a timeout saying ";; connection timed out; no 
> servers could be reached". So it appears that is the reason why the mail 
> isn't getting through - it can't find the domain that is hosted on this 
> server.
>
> I've tried restarting DNS through the gui or via the command line using 
> named restart to no avail. I've tried restarting sendmail via the shell. 
> Nothing I try seems to un-stick this except re-booting that VPS. 
> HOWEVER, if I notice the problem late at night I can just let it go and 
> one of the automated nightly server tasks will un-stick it. Does anyone 
> have any ideas what it is that may be working overnight that I can try 
> via the command line? Re-booting is too big a hammer to hit it with 
> during the day when we have important activities going on that we don't 
> want to interrupt.
>
>
Check with whois
   whois usms.org
Name Server:ADMIN.USMS.ORG
Name Server:NS.USMS.ORG

dig usms.com @NS.USMS.ORG

; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.17.rc1.el6_4.5 <<>> usms.com @NS.USMS.ORG
;; global options: +cmd
;; connection timed out; no servers could be reached

dig usms.com @admin.USMS.ORG

; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.17.rc1.el6_4.5 <<>> usms.com
@admin.USMS.ORG
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: REFUSED, id: 30018
;; flags: qr rd; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0
;; WARNING: recursion requested but not available

;; QUESTION SECTION:
;usms.com.            IN    A

--
gerald