Home > IT Answers > Exchange > DNS not resolving from particular ISP
VSNLISP
0 pts.
 DNS not resolving from particular ISP
Exchange security, Exchange
Server is hosted the collocation mail server in Reliance IDC pls find the detail as below

220.226.206.216 ......... ns1.parle.biz

220.226.206.217 .......... ns2.parle.biz

202.138.101.204 .......... ns3.parle.biz

I am using VSNL Link to access server located in reliance IDC & using Reliance DNS Ip address on VSNL link. to reach my server.

But when i try to trace my server Ip with IP address it is reachable , But when i use Hostname to Telnet or taceroute is not reachable from VSNL link

When I access my server from another ISP link it is reachable.

Now that mean the problem is with the VSNL link

When i do traceroute with host name it getting drop at my firewall befor my server hosted in Reliance IDC.

Kindly find the detail below

One of their servers is not resolving its own domain name as marked in red color below:

--------------------------------------

> server 220.226.206.217

Default Server: ns2.parle.biz

Address: 220.226.206.217



> parle.biz

Server: ns2.parle.biz

Address: 220.226.206.217



Name: parle.biz

Addresses: 202.138.101.204, 220.226.206.217, 220.226.206.216

--------------------------------------



> server 220.226.206.216

Default Server: ns1.parle.biz

Address: 220.226.206.216



> parle.biz

Server: ns1.parle.biz

Address: 220.226.206.216



Name: parle.biz

Addresses: 202.138.101.204, 220.226.206.217, 220.226.206.216

--------------------------------------



> server 202.138.101.204

Default Server: ns3.parle.biz

Address: 202.138.101.204



> parle.biz

Server: ns3.parle.biz

Address: 202.138.101.204



*** ns3.parle.biz can't find parle.biz: No response from server

--------------------------------------



While tracing it was found that we were able to reach up to 220.226.206.214 at Reliance IDC as below:



#traceroute 220.226.206.216



traceroute to 220.226.206.216 (220.226.206.216), 30 hops max, 40 byte packets

1)BMFW.vsnl.net (202.54.1.40) 0.360 ms 0.280 ms 0.195 ms
2)vsb-lan.152.static.vsnl.net.in (202.54.1.152)0.454 ms 0.280 ms 0.261 ms

3)hyd-mum-2nd-stm1.Bbone.vsnl.net.in (202.54.2.77) 0.889 ms 0.873 ms 0.967 ms

4)203.197.33.206.static.vsnl.net.in (203.197.33.206) 1.235 ms 1.191 ms 1.038 ms

5)220.227.57.94 (220.227.57.94) 74.643 ms 33.444 ms 59.617 ms

6)220.224.185.173 (220.224.185.173) 2.947 ms 220.224.184.30 (220.224.184.30) 3.159 ms 2.881 ms

7)202.138.117.210 (202.138.117.210) 2.896 ms 3.249 ms 3.039 ms

8)202.138.113.1 (202.138.113.1) 3.093 ms 3.075 ms 2.984 ms

9 * * *

10)ns3.parle.biz (220.226.206.214)3.435 ms 3.368 ms 3.310 ms

11* * *
12 * * *
13 * * *
14 * * *
15 * * *
16 * * *

My TTL value is TTL=3600 default
There is also a NAT done between by public & private IP to reach the mail server.

Kindly let me know that the problem is with TTL or firewall.
ASKED: May 22, 2007  5:55 AM GMT
UPDATED: May 23, 2007  1:50:45 AM GMT
RELATED QUESTIONS
bobkberg
1,010 pts.
Answer Wiki:
You did not mention whether or not you are using the same name server internally as we see externally. I queried the name servers ns1 and ns2.parle.biz, and got:

Name: parle.biz
Addresses:202.138.101.204, 220.226.206.217, 220.226.206.216

This leads me to suspect that you may have an internal name server referencing the same domain, but a different set of data files.

Try doing the lookup/telnet/whatever by hostname terminated by a period - so that it looks like "mail.parle.biz."

Also, when you open nslookup at the command prompt, check the SOA value for parle.biz internally, and see what it says about it.

Example:
nslookup
> set type=soa
> parle.biz

And let us know what results you get.

Bob
Last Wiki Answer Submitted:  May 22, 2007  7:58 PM (GMT)  by  bobkberg   1,010 pts.
To see other answers submitted to the Answer Wiki View Answer History.
RSS - Discussions Help
Discuss This Question:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _



 

Kinldy find the result as below

> set type=soa
> parle.biz
Server: hq-dc-01.vsnl.co.in
Address: 172.16.24.39

Non-authoritative answer:
parle.biz.co.in
primary name server = ns1.sedoparking.com
responsible mail addr = hostmaster.sedo.de
serial = 2006113001
refresh = 86400 (1 day)
retry = 7200 (2 hours)
expire = 604800 (7 days)
default TTL = 86400 (1 day)

ns1.sedoparking.com internet address = 212.227.86.6

Kinldy let me know should i do to resolve the issue

VSNLISP
 0 pts.
 

Ok - it appears from your reply that that the SOA (Start Of Authority) server that you see from your desktop is an internal name server with a private IP address (172.16.whatever)

parle.biz.co.in is NOT the same as parle.biz.

What I’d recommend is one of two tactics…

1) make your internal name server a secondary to your external one, and let the zone transfers happen automatically.

or

2) Drop the internal zone name parle.biz, and let the resolution come from the external name server where your internal name server uses its forwarder definitions to find the authoritative source.

What you appear to have at the moment is a split DNS - which is not a bad thing - as long as it is managed with the understanding that you’ll have to manually keep the two sets of zone files in synchronization manually.

If that’s still not clear, then you may have to contact some local DNS expert directly. This forum does not allow other suggestions.

Bob

bobkberg
 1,010 pts.