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  #1  
Old 28th May 2008, 15:13
craig baker craig baker is offline
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Default odd DNS problem????????

on my continuing semi-newb problem series, I have a nasty thing going on (I fear).

my server is a dual opteron 8gb 600gb scsi DAM nice fast server.
TOP shows 99+ idle at all times. there is very little load on it as far as i can tell.

BUT - I'm seeing weird DNS responses and need some assistance - even willing to pay anyone who wants to log in and help me out.
(cdb@craigscomputers.net).

what I'm seeing is rather odd behaviour.

If I do something that needs DNS resolution (my nameserver on the server is current centos 5.1 named) - say I pull up a webpage. the first time or two I pull up an address (only some of them alas) - the browser times out. 'server not responding' etc. type messages.
then I refresh again and it pops up!

so obviously named is not responding fast enough (or at all)? the first 2 requests.

this is not fully repeatable but I think its also why some of my customers tell me they cant send or retrive mail (most are just fine). they send me screenshots of errors like 'cant find mail server' etc.

now if they try the send/receive again they will eventually get it through but its obviously something I need to resolve.

any suggestions? anythign to look at???

the nameserver is ns5.cdbsystems.com if anyone wants to run tests on it

and your help will be MOST appreciated (and even rewarded)

thanks
cdb.
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  #2  
Old 29th May 2008, 06:28
zcworld zcworld is offline
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ok problem
ns4 is offline

im not going to say the IP
but when i try it
nothing loaded
maybe thats your problem
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  #3  
Old 29th May 2008, 12:40
craig baker craig baker is offline
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Default NS4 problem

true, NS4 is down (and probably will stay down) but I would have thought everything would have expired from NS4 by now and NS5 would have replaced everything...
when I restarted named on NS5 I upped all serial numbers so I would have thought all caches would have replaced ns4 info by ns5 by now...
cdb.
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Old 29th May 2008, 14:12
zcworld zcworld is offline
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did that fix the problem with the timeouts in the now
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  #5  
Old 29th May 2008, 16:25
craig baker craig baker is offline
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Default DNS issues

I've redirected ns4 to the same ip as ns5 I'll see if that takes care of the odd delays.
thanks
cdb.
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  #6  
Old 30th May 2008, 22:27
craig baker craig baker is offline
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Default DNS issues

could you all do traceroutes to ns5.cdbsystems.com?
I've been told by one customer he's seeing bad latencies but I'm not seeing anything rude.
would appreciate it
cdb.
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  #7  
Old 31st May 2008, 02:25
craig baker craig baker is offline
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Default more weirdness - continuing DNS issue?????

I just was doing some traceroutes to one of my domains and:

E:\Documents and Settings\cdb>ping mail.weblawdog.com

Pinging mail.weblawdog.com [71.163.161.26] with 32 bytes of data:

Reply from 71.163.161.26: bytes=32 time=17ms TTL=247
Reply from 71.163.161.26: bytes=32 time=15ms TTL=247

Ping statistics for 71.163.161.26:
Packets: Sent = 2, Received = 2, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 15ms, Maximum = 17ms, Average = 16ms
Control-C
^C
------------a bit later cdb:

E:\Documents and Settings\cdb>tracert mail.weblawdog.com
Unable to resolve target system name mail.weblawdog.com.

----- few secs later
E:\Documents and Settings\cdb>tracert mail.weblawdog.com

Tracing route to admin.weblawdog.com [71.163.161.26]
over a maximum of 30 hops:

1 * * * Request timed out.
2 9 ms 7 ms 6 ms 10.7.168.1
3 7 ms 7 ms 7 ms ip72-219-223-97.dc.dc.cox.net [72.219.223.97]
4 7 ms 7 ms 15 ms mrfddsrj01-ge110.rd.dc.cox.net [68.100.0.161]
5 11 ms 18 ms 8 ms ashbbbrj01-ae0.0.r2.as.cox.net [68.1.0.220]
6 41 ms 10 ms 11 ms so-7-3-0-0.BB-RTR1.RES.verizon-gni.net [130.81.1
0.89]
7 11 ms 11 ms 9 ms P15-0.LCR-05.WASHDC.verizon-gni.net [130.81.28.1
45]
8 14 ms 11 ms 11 ms L1.VFTTP-29.WASHDC.verizon-gni.net [130.81.243.1
29]
9 25 ms 14 ms 14 ms mail.weblawdog.com [71.163.161.26]

Trace complete.


any ideas what is going on?????
cdb.
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  #8  
Old 31st May 2008, 10:36
zcworld zcworld is offline
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[zcworld@zcworld ~]$ dig @ns5.cdbsystems.com cdbsystem.com

; <<>> DiG 9.5.0b2 <<>> @ns5.cdbsystems.com cdbsystem.com
; (1 server found)
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 45116
;; flags: qr rd; QUERY: 1, ANSWER: 0, AUTHORITY: 13, ADDITIONAL: 0
;; WARNING: recursion requested but not available

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

;; AUTHORITY SECTION:
. 3600000 IN NS A.ROOT-SERVERS.NET.
. 3600000 IN NS B.ROOT-SERVERS.NET.
. 3600000 IN NS C.ROOT-SERVERS.NET.
. 3600000 IN NS D.ROOT-SERVERS.NET.
. 3600000 IN NS E.ROOT-SERVERS.NET.
. 3600000 IN NS F.ROOT-SERVERS.NET.
. 3600000 IN NS G.ROOT-SERVERS.NET.
. 3600000 IN NS H.ROOT-SERVERS.NET.
. 3600000 IN NS I.ROOT-SERVERS.NET.
. 3600000 IN NS J.ROOT-SERVERS.NET.
. 3600000 IN NS K.ROOT-SERVERS.NET.
. 3600000 IN NS L.ROOT-SERVERS.NET.
. 3600000 IN NS M.ROOT-SERVERS.NET.

;; Query time: 320 msec
;; SERVER: 71.163.161.26#53(71.163.161.26)
;; WHEN: Sat May 31 17:50:26 2008
;; MSG SIZE rcvd: 242

[zcworld@zcworld ~]$ dig @ns5.cdbsystems.com www.cdbsystem.com

; <<>> DiG 9.5.0b2 <<>> @ns5.cdbsystems.com www.cdbsystem.com
; (1 server found)
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 43094
;; flags: qr rd; QUERY: 1, ANSWER: 0, AUTHORITY: 13, ADDITIONAL: 0
;; WARNING: recursion requested but not available

;; QUESTION SECTION:
;www.cdbsystem.com. IN A

;; AUTHORITY SECTION:
. 3600000 IN NS M.ROOT-SERVERS.NET.
. 3600000 IN NS A.ROOT-SERVERS.NET.
. 3600000 IN NS B.ROOT-SERVERS.NET.
. 3600000 IN NS C.ROOT-SERVERS.NET.
. 3600000 IN NS D.ROOT-SERVERS.NET.
. 3600000 IN NS E.ROOT-SERVERS.NET.
. 3600000 IN NS F.ROOT-SERVERS.NET.
. 3600000 IN NS G.ROOT-SERVERS.NET.
. 3600000 IN NS H.ROOT-SERVERS.NET.
. 3600000 IN NS I.ROOT-SERVERS.NET.
. 3600000 IN NS J.ROOT-SERVERS.NET.
. 3600000 IN NS K.ROOT-SERVERS.NET.
. 3600000 IN NS L.ROOT-SERVERS.NET.

;; Query time: 314 msec
;; SERVER: 71.163.161.26#53(71.163.161.26)
;; WHEN: Sat May 31 17:50:46 2008
;; MSG SIZE rcvd: 246

[zcworld@zcworld ~]$





the DNS / NS server : 71.163.161.26 goes to the web site
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  #9  
Old 31st May 2008, 10:46
zcworld zcworld is offline
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have you try doing an clean rebuild of your DNS
and take it offline if you can like for 30 hrs to clean out any old cache of your DNS ... and than reload ...

or try another DNS server for an short time to see if its fix the problem ...


also tell them to check there DNS server list they are using
make they got an iffy DNS server in there list they are on .....
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  #10  
Old 31st May 2008, 16:14
craig baker craig baker is offline
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Default not sure whats wrong zcworld

I see your printout but you are digging www.cdbsystem.com
not www.cdbsystemS.com

I think what you got was what would be expected!
cdb.
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