Sometimes DNS would not work

  • Thread starter Thread starter frankcchan
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frankcchan

Some of the 2000 clients machine could not solve DNS
occationally. Some emails bound back but sent ok from
other machines. No machine could ping www.msn.com or
www.aol.com but ie is ok. Please help.
 
In
Some of the 2000 clients machine could not solve DNS
occationally. Some emails bound back but sent ok from
other machines. No machine could ping www.msn.com or
www.aol.com but ie is ok. Please help.
Click to expand...

Does nslookup resolve?
Are these clients members of a domain?
If they are domain members are they pointing to the DC for DNS?
If there is a local DNS server did you delete the "." (root) forward lookup
zone?
300202 - HOW TO: Configure DNS for Internet Access in Windows 2000
http://support.microsoft.com/?id=300202&FR=1

BTW, just for info all machines in an AD Domain must point to the local DNS
*ONLY*
You may be wondering why being in a domain makes a difference, it is because
DNS is required for an AD Domain and all machines in the domain MUST point
to this DNS server only including the DNS machine (usually the DC) itself.
If there is know gateway on the DC when you install DNS DCPROMO will create
a "." forward lookup zone and until this zone is delete DNS cannot resolve
internet names and some admins will put an ISP's DNS in the NIC properties
of the machines to give internet access. THIS is a major mistake, it causes
errors because the DC cannot resolve internet names and the ISP cannot
resolve your network names.
 
nslookup shows as following:

C:\>nslookup www.msn.com
Server: fremontbdc.pcs-ww.com
Address: 172.16.0.2

Non-authoritative answer:
Name: www.msn.com
Addresses: 207.68.171.245, 207.68.171.247,
207.68.172.234, 207.68.173.244
207.68.173.254, 207.68.171.244

Those clients are members of a domain and they are
pointing to the BDC for DNS (Now) I deleted the ISP DNS.
There is no "." (root) forward lookup zone except in
Cached Lookups.

I can not ping www.msn.com, www.aol.com but
www.yahoo.com. Any reason?

-----Original Message-----
In (e-mail address removed)
Click to expand...
 
In (e-mail address removed) <[email protected]>
posted a question
Then Kevin replied below:
nslookup shows as following:

C:\>nslookup www.msn.com
Server: fremontbdc.pcs-ww.com
Address: 172.16.0.2

Non-authoritative answer:
Name: www.msn.com
Addresses: 207.68.171.245, 207.68.171.247,
207.68.172.234, 207.68.173.244
207.68.173.254, 207.68.171.244

Those clients are members of a domain and they are
pointing to the BDC for DNS (Now) I deleted the ISP DNS.
There is no "." (root) forward lookup zone except in
Cached Lookups.

I can not ping www.msn.com, www.aol.com but
www.yahoo.com. Any reason?
Click to expand...

Well it resolves right but I'm not suprised you cannot ping aol or msn
because ICMP is blocked. Nobody can ping them.
 
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