DNS Caching addresses

  • Thread starter Thread starter tshad
  • Start date Start date
T

tshad

I have a problem with a VPN Client program where address I enter seems to
get cached. Using a Windows XP program.

I enter something like:

ping www.fts.com

and get an address of something like:

67.100.12.15.

I then fire up my VPN program which will make my machine look like it is on
the local network. At that point, if I type in the same ping statment, I
should get something like:

10.0.0.15.

But instead I still get 67.100.12.15.

This only happens when I do the ping before starting my VPN program.

If I reboot the machine, then everything is OK. I assume that www.fts.com
with the IP address is cached somewhere.

If this is the case, where would it be and how do I see it and delete it?

Thanks,

Tom
 
ipconfig /displaydns

You can change this behavior by turning off the DNS client service.

Doug Sherman
MCSE, MCSA, MCP+I, MVP
 
Doug Sherman said:
ipconfig /displaydns

You can change this behavior by turning off the DNS client service.
Click to expand...

After you mentioned it, I looked and found that you can clear the cache by
doing: ipconfig /flushdns.

Thanks,

Tom
 
Yes - you can clear the cache with ipconfig /flushdns, or you can turn off
client side caching altogether by stopping the DNS client service.

Doug Sherman
MCSE, MCSA, MCP+I, MVP
 
Doug Sherman said:
Yes - you can clear the cache with ipconfig /flushdns, or you can turn off
client side caching altogether by stopping the DNS client service.
Click to expand...

All makes sense.

I played with this quite a bit and found that if I turned off the cache
service, it goes out to the outside DNS servers each time. I did find an
interesting thing when I tried to ping various Names, such as www.yahoo.com.
I got a list of servers and then each one in the list has its own display:
**********************************************
www.yahoo.com.
------------------------------------------------------
Record Name . . . . . : www.yahoo.com
Record Type . . . . . : 5
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Answer
CNAME Record . . . . :
www.yahoo.akadns.net

Record Name . . . . . : www.yahoo.akadns.net
Record Type . . . . . : 1
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . :
209.131.36.158

Record Name . . . . . : akadns.net
Record Type . . . . . : 2
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Authority
NS Record . . . . . :
zc.akadns.org

Record Name . . . . . : akadns.net
Record Type . . . . . : 2
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Authority
NS Record . . . . . :
zd.akadns.org

Record Name . . . . . : akadns.net
Record Type . . . . . : 2
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Authority
NS Record . . . . . :
eur4.akadns.net

Record Name . . . . . : akadns.net
Record Type . . . . . : 2
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Authority
NS Record . . . . . :
eur8.akadns.net

Record Name . . . . . : akadns.net
Record Type . . . . . : 2
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Authority
NS Record . . . . . :
usw5.akadns.net

Record Name . . . . . : akadns.net
Record Type . . . . . : 2
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Authority
NS Record . . . . . :
asia4.akadns.net

Record Name . . . . . : akadns.net
Record Type . . . . . : 2
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Authority
NS Record . . . . . :
asia9.akadns.net

Record Name . . . . . : akadns.net
Record Type . . . . . : 2
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Authority
NS Record . . . . . :
za.akadns.org

Record Name . . . . . : akadns.net
Record Type . . . . . : 2
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Authority
NS Record . . . . . :
zb.akadns.org

Record Name . . . . . : za.akadns.org
Record Type . . . . . : 1
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Additional
A (Host) Record . . . :
81.52.250.134

Record Name . . . . . : zb.akadns.org
Record Type . . . . . : 1
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Additional
A (Host) Record . . . :
206.132.100.105

Record Name . . . . . : zc.akadns.org
Record Type . . . . . : 1
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Additional
A (Host) Record . . . :
69.45.78.3

Record Name . . . . . : zd.akadns.org
Record Type . . . . . : 1
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Additional
A (Host) Record . . . :
65.203.234.28

Record Name . . . . . : eur4.akadns.net
Record Type . . . . . : 1
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Additional
A (Host) Record . . . :
195.219.3.169

Record Name . . . . . : eur8.akadns.net
Record Type . . . . . : 1
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Additional
A (Host) Record . . . :
62.4.69.96

Record Name . . . . . : usw5.akadns.net
Record Type . . . . . : 1
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Additional
A (Host) Record . . . :
63.241.73.200

Record Name . . . . . : asia4.akadns.net
Record Type . . . . . : 1
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Additional
A (Host) Record . . . :
61.213.147.96

Record Name . . . . . : asia9.akadns.net
Record Type . . . . . : 1
Time To Live . . . . : 22
Data Length . . . . . : 4
Section . . . . . . . : Additional
A (Host) Record . . . :
220.73.220.4


eur8.akadns.net.
------------------------------------------------------
Record Name . . . . . : eur8.akadns.net
Record Type . . . . . : 1
Time To Live . . . . : 13526
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . :
62.4.69.96


za.akadns.org.
------------------------------------------------------
Record Name . . . . . : za.akadns.org
Record Type . . . . . : 1
Time To Live . . . . : 3298
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . :
81.52.250.134
....
************************************************

Why is it going to all these servers and why is it caching all of them if
it only needs the top couple?

My ping got me:

Pinging www.yahoo.akadns.net [209.131.36.158] with 32 bytes of data:

which is the top record in my list that points to the 2nd one.

Not quite sure why.

Thanks,

Tom
 
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