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How come IPConfig /flushdns doesn't work??....

 
 
Penang
Guest
Posts: n/a
 
      23rd Oct 2008
Hi, all !

I've tested IPConfig /flushdns command and found out that it doesn't
work. But before I go on, here are some background details...

My connection to the net is via ADSL, dynamic link. In theory, the use
of the following 3 commands:-

ipconfig /flushdns
ipconfig /release
ipconfig /renew

supposed to flush out the "old" dns, and obtain a "new" one.

So I made a batch file (ip.bat) with the following command:-

ipconfig /flushdns
ipconfig /release
ipconfig /renew
ipconfig /all

and run 2 tests, about 20 minutes apart.

The result is, the dns and the IPs stayed the same !!

The IP for test #1 is 118.101.50.219, so is test #2 !

I wonder if I have done something wrong. If I do, please tell me.

Thank you !


= = = = =============================================


Here are the complete test results: ----

Test #1:

D:\>ipconfig/flushdns

Windows IP Configuration
Successfully flushed the DNS Resolver Cache.

D:\>ipconfig/release

Windows IP Configuration


Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . :
IP Address. . . . . . . . . . . . : 0.0.0.0
Subnet Mask . . . . . . . . . . . : 0.0.0.0
Default Gateway . . . . . . . . . :

PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
Connection-specific DNS Suffix . :
IP Address. . . . . . . . . . . . : 118.101.50.219
Subnet Mask . . . . . . . . . . . : 255.255.255.255
Default Gateway . . . . . . . . . : 118.101.50.219


D:\>ipconfig/renew

Windows IP Configuration

Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . :
IP Address. . . . . . . . . . . . : 192.168.1.3
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.1.1

PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
Connection-specific DNS Suffix . :
IP Address. . . . . . . . . . . . : 118.101.50.219
Subnet Mask . . . . . . . . . . . : 255.255.255.255
Default Gateway . . . . . . . . . : 118.101.50.219

D:\>ipconfig/all

Windows IP Configuration

Host Name . . . . . . . . . . . . : MetalShaving
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Unknown
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No

Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : VIA Compatable Fast
Ethernet Adapter #2
Physical Address. . . . . . . . . : 00-E0-4D-32-CE-8F
Dhcp Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IP Address. . . . . . . . . . . . : 192.168.1.3
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.1.1
DHCP Server . . . . . . . . . . . : 192.168.1.1
DNS Servers . . . . . . . . . . . : 192.168.1.1
Lease Obtained. . . . . . . . . . : Wednesday, October 22,
2008 11:33:36 PM
Lease Expires . . . . . . . . . . : Friday, November 21,
2008 11:33:36 PM

PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : WAN (PPP/SLIP) Interface
Physical Address. . . . . . . . . : 00-53-45-00-00-00
Dhcp Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 118.101.50.219
Subnet Mask . . . . . . . . . . . : 255.255.255.255
Default Gateway . . . . . . . . . : 118.101.50.219
DNS Servers . . . . . . . . . . . : 202.188.0.133
202.188.1.5


Test #2:


D:\>ipconfig/flushdns

Windows IP Configuration
Successfully flushed the DNS Resolver Cache.

D:\>ipconfig/release

Windows IP Configuration


Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . :
IP Address. . . . . . . . . . . . : 0.0.0.0
Subnet Mask . . . . . . . . . . . : 0.0.0.0
Default Gateway . . . . . . . . . :

PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
Connection-specific DNS Suffix . :
IP Address. . . . . . . . . . . . : 118.101.50.219
Subnet Mask . . . . . . . . . . . : 255.255.255.255
Default Gateway . . . . . . . . . : 118.101.50.219


D:\>ipconfig/renew

Windows IP Configuration

Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . :
IP Address. . . . . . . . . . . . : 192.168.1.3
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.1.1

PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
Connection-specific DNS Suffix . :
IP Address. . . . . . . . . . . . : 118.101.50.219
Subnet Mask . . . . . . . . . . . : 255.255.255.255
Default Gateway . . . . . . . . . : 118.101.50.219

D:\>ipconfig/all

Windows IP Configuration

Host Name . . . . . . . . . . . . : MetalShaving
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Unknown
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No

Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : VIA Compatable Fast
Ethernet Adapter #2
Physical Address. . . . . . . . . : 00-E0-4D-32-CE-8F
Dhcp Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IP Address. . . . . . . . . . . . : 192.168.1.3
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.1.1
DHCP Server . . . . . . . . . . . : 192.168.1.1
DNS Servers . . . . . . . . . . . : 192.168.1.1
Lease Obtained. . . . . . . . . . : Wednesday, October 22,
2008 11:58:36 PM
Lease Expires . . . . . . . . . . : Friday, November 21,
2008 11:58:36 PM

PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : WAN (PPP/SLIP) Interface
Physical Address. . . . . . . . . : 00-53-45-00-00-00
Dhcp Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 118.101.50.219
Subnet Mask . . . . . . . . . . . : 255.255.255.255
Default Gateway . . . . . . . . . : 118.101.50.219
DNS Servers . . . . . . . . . . . : 202.188.0.133
202.188.1.5
 
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MEB
Guest
Posts: n/a
 
      23rd Oct 2008
"Penang" <(E-Mail Removed)> wrote in message
news:bbdc21c9-126b-4da5-b4fd-(E-Mail Removed)...
| Hi, all !
|
| I've tested IPConfig /flushdns command and found out that it doesn't
| work. But before I go on, here are some background details...
|
|My connection to the net is via ADSL, dynamic link. In theory, the use
|of the following 3 commands:-
|***IP config info cut****

So what's your problem? And why all these cross-posts....

*You* obtain your IP and other from the modem/router when dynamic.
Want a new address? Physically power down [disconnect from power for about
20 minutes] the modem/router though its likely assigned via your provider
and hard set when initially installed [they have to know who you are after
all].
*IF* you received software with the ADSL modem you may be able to adjust the
*local IP ranges* .... you must contact your provider if you want to change
the ADSL IP/device ID.

--
MEB
http://peoplescounsel.org
a Peoples' counsel
_ _
~~



 
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Sinner
Guest
Posts: n/a
 
      23rd Oct 2008

"MEB" <meb@not (E-Mail Removed)> wrote in message news:(E-Mail Removed)...
>
> *You* obtain your IP and other from the modem/router when dynamic.
> Want a new address? Physically power down [disconnect from power for about
> 20 minutes] the modem/router though its likely assigned via your provider
> and hard set when initially installed [they have to know who you are after
> all].
> *IF* you received software with the ADSL modem you may be able to adjust the
> *local IP ranges* .... you must contact your provider if you want to change
> the ADSL IP/device ID.
>


My former service provider, a cable service, told me my IP was dynamic also. In fact, they have a finite number of IP addresses, and for me to get a new one, I'd have to power down for at least 3 days. Anything less, and I'd just be reassigned the same address when I logged back on.

My current provider, Bellsouth FastAccess, has provides me with a Static IP. It's great if you want to self-host a website, FTP server, etc., but it sucks if your IP has been banned by several forums. For that, they invented the Proxy Server.
 
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Jack \(MVP-Networking\).
Guest
Posts: n/a
 
      23rd Oct 2008
Hi
Dynamic IP from the ISP does not imply that every time you log On or Off the
IP would change.
It means that you are Not entrusted with one specific IP, but the schedule
of the dynamic changes are up to the ISP's server.
Some ISP's IPs do not change for weeks even if you disconnect the modem from
the line, and reconnect after few days.
BTW, flushdns is a local command and does not affect the Internet connection
per-se.
Jack (MS, MVP-Networking)


"Penang" <(E-Mail Removed)> wrote in message
news:bbdc21c9-126b-4da5-b4fd-(E-Mail Removed)...
> Hi, all !
>
> I've tested IPConfig /flushdns command and found out that it doesn't
> work. But before I go on, here are some background details...
>
> My connection to the net is via ADSL, dynamic link. In theory, the use
> of the following 3 commands:-
>
> ipconfig /flushdns
> ipconfig /release
> ipconfig /renew
>
> supposed to flush out the "old" dns, and obtain a "new" one.
>
> So I made a batch file (ip.bat) with the following command:-
>
> ipconfig /flushdns
> ipconfig /release
> ipconfig /renew
> ipconfig /all
>
> and run 2 tests, about 20 minutes apart.
>
> The result is, the dns and the IPs stayed the same !!
>
> The IP for test #1 is 118.101.50.219, so is test #2 !
>
> I wonder if I have done something wrong. If I do, please tell me.
>
> Thank you !
>
>
> = = = = =============================================
>
>
> Here are the complete test results: ----
>
> Test #1:
>
> D:\>ipconfig/flushdns
>
> Windows IP Configuration
> Successfully flushed the DNS Resolver Cache.
>
> D:\>ipconfig/release
>
> Windows IP Configuration
>
>
> Ethernet adapter Local Area Connection:
> Connection-specific DNS Suffix . :
> IP Address. . . . . . . . . . . . : 0.0.0.0
> Subnet Mask . . . . . . . . . . . : 0.0.0.0
> Default Gateway . . . . . . . . . :
>
> PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
> Connection-specific DNS Suffix . :
> IP Address. . . . . . . . . . . . : 118.101.50.219
> Subnet Mask . . . . . . . . . . . : 255.255.255.255
> Default Gateway . . . . . . . . . : 118.101.50.219
>
>
> D:\>ipconfig/renew
>
> Windows IP Configuration
>
> Ethernet adapter Local Area Connection:
>
> Connection-specific DNS Suffix . :
> IP Address. . . . . . . . . . . . : 192.168.1.3
> Subnet Mask . . . . . . . . . . . : 255.255.255.0
> Default Gateway . . . . . . . . . : 192.168.1.1
>
> PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
> Connection-specific DNS Suffix . :
> IP Address. . . . . . . . . . . . : 118.101.50.219
> Subnet Mask . . . . . . . . . . . : 255.255.255.255
> Default Gateway . . . . . . . . . : 118.101.50.219
>
> D:\>ipconfig/all
>
> Windows IP Configuration
>
> Host Name . . . . . . . . . . . . : MetalShaving
> Primary Dns Suffix . . . . . . . :
> Node Type . . . . . . . . . . . . : Unknown
> IP Routing Enabled. . . . . . . . : No
> WINS Proxy Enabled. . . . . . . . : No
>
> Ethernet adapter Local Area Connection:
> Connection-specific DNS Suffix . :
> Description . . . . . . . . . . . : VIA Compatable Fast
> Ethernet Adapter #2
> Physical Address. . . . . . . . . : 00-E0-4D-32-CE-8F
> Dhcp Enabled. . . . . . . . . . . : Yes
> Autoconfiguration Enabled . . . . : Yes
> IP Address. . . . . . . . . . . . : 192.168.1.3
> Subnet Mask . . . . . . . . . . . : 255.255.255.0
> Default Gateway . . . . . . . . . : 192.168.1.1
> DHCP Server . . . . . . . . . . . : 192.168.1.1
> DNS Servers . . . . . . . . . . . : 192.168.1.1
> Lease Obtained. . . . . . . . . . : Wednesday, October 22,
> 2008 11:33:36 PM
> Lease Expires . . . . . . . . . . : Friday, November 21,
> 2008 11:33:36 PM
>
> PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
> Connection-specific DNS Suffix . :
> Description . . . . . . . . . . . : WAN (PPP/SLIP) Interface
> Physical Address. . . . . . . . . : 00-53-45-00-00-00
> Dhcp Enabled. . . . . . . . . . . : No
> IP Address. . . . . . . . . . . . : 118.101.50.219
> Subnet Mask . . . . . . . . . . . : 255.255.255.255
> Default Gateway . . . . . . . . . : 118.101.50.219
> DNS Servers . . . . . . . . . . . : 202.188.0.133
> 202.188.1.5
>
>
> Test #2:
>
>
> D:\>ipconfig/flushdns
>
> Windows IP Configuration
> Successfully flushed the DNS Resolver Cache.
>
> D:\>ipconfig/release
>
> Windows IP Configuration
>
>
> Ethernet adapter Local Area Connection:
> Connection-specific DNS Suffix . :
> IP Address. . . . . . . . . . . . : 0.0.0.0
> Subnet Mask . . . . . . . . . . . : 0.0.0.0
> Default Gateway . . . . . . . . . :
>
> PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
> Connection-specific DNS Suffix . :
> IP Address. . . . . . . . . . . . : 118.101.50.219
> Subnet Mask . . . . . . . . . . . : 255.255.255.255
> Default Gateway . . . . . . . . . : 118.101.50.219
>
>
> D:\>ipconfig/renew
>
> Windows IP Configuration
>
> Ethernet adapter Local Area Connection:
>
> Connection-specific DNS Suffix . :
> IP Address. . . . . . . . . . . . : 192.168.1.3
> Subnet Mask . . . . . . . . . . . : 255.255.255.0
> Default Gateway . . . . . . . . . : 192.168.1.1
>
> PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
> Connection-specific DNS Suffix . :
> IP Address. . . . . . . . . . . . : 118.101.50.219
> Subnet Mask . . . . . . . . . . . : 255.255.255.255
> Default Gateway . . . . . . . . . : 118.101.50.219
>
> D:\>ipconfig/all
>
> Windows IP Configuration
>
> Host Name . . . . . . . . . . . . : MetalShaving
> Primary Dns Suffix . . . . . . . :
> Node Type . . . . . . . . . . . . : Unknown
> IP Routing Enabled. . . . . . . . : No
> WINS Proxy Enabled. . . . . . . . : No
>
> Ethernet adapter Local Area Connection:
> Connection-specific DNS Suffix . :
> Description . . . . . . . . . . . : VIA Compatable Fast
> Ethernet Adapter #2
> Physical Address. . . . . . . . . : 00-E0-4D-32-CE-8F
> Dhcp Enabled. . . . . . . . . . . : Yes
> Autoconfiguration Enabled . . . . : Yes
> IP Address. . . . . . . . . . . . : 192.168.1.3
> Subnet Mask . . . . . . . . . . . : 255.255.255.0
> Default Gateway . . . . . . . . . : 192.168.1.1
> DHCP Server . . . . . . . . . . . : 192.168.1.1
> DNS Servers . . . . . . . . . . . : 192.168.1.1
> Lease Obtained. . . . . . . . . . : Wednesday, October 22,
> 2008 11:58:36 PM
> Lease Expires . . . . . . . . . . : Friday, November 21,
> 2008 11:58:36 PM
>
> PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
> Connection-specific DNS Suffix . :
> Description . . . . . . . . . . . : WAN (PPP/SLIP) Interface
> Physical Address. . . . . . . . . : 00-53-45-00-00-00
> Dhcp Enabled. . . . . . . . . . . : No
> IP Address. . . . . . . . . . . . : 118.101.50.219
> Subnet Mask . . . . . . . . . . . : 255.255.255.255
> Default Gateway . . . . . . . . . : 118.101.50.219
> DNS Servers . . . . . . . . . . . : 202.188.0.133
> 202.188.1.5


 
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Gregg Hill
Guest
Posts: n/a
 
      23rd Oct 2008
Hello!

The "/flushdns" command line switch has nothing to do with the IP addresses
of your DNS servers. It merely flushes the local DNS cache on your system.

Even if you were to get a new IP address by doing release/renew, you should
expect the DNS servers to remain the same, because the ISP is not normally
changing its DNS servers.

To see the effect of a /flushdns, do the following at a command prompt:

ipconfig /displaydns

That will display your current DNS cache.

ipconfig /flushdns

Flushes the cache.

ipconfig /displaydns

Displays the cleared cache.

Do a

ipconfig /?

at the prompt to see all the options.

Gregg Hill





"Penang" <(E-Mail Removed)> wrote in message
news:bbdc21c9-126b-4da5-b4fd-(E-Mail Removed)...
> Hi, all !
>
> I've tested IPConfig /flushdns command and found out that it doesn't
> work. But before I go on, here are some background details...
>
> My connection to the net is via ADSL, dynamic link. In theory, the use
> of the following 3 commands:-
>
> ipconfig /flushdns
> ipconfig /release
> ipconfig /renew
>
> supposed to flush out the "old" dns, and obtain a "new" one.
>
> So I made a batch file (ip.bat) with the following command:-
>
> ipconfig /flushdns
> ipconfig /release
> ipconfig /renew
> ipconfig /all
>
> and run 2 tests, about 20 minutes apart.
>
> The result is, the dns and the IPs stayed the same !!
>
> The IP for test #1 is 118.101.50.219, so is test #2 !
>
> I wonder if I have done something wrong. If I do, please tell me.
>
> Thank you !
>
>
> = = = = =============================================
>
>
> Here are the complete test results: ----
>
> Test #1:
>
> D:\>ipconfig/flushdns
>
> Windows IP Configuration
> Successfully flushed the DNS Resolver Cache.
>
> D:\>ipconfig/release
>
> Windows IP Configuration
>
>
> Ethernet adapter Local Area Connection:
> Connection-specific DNS Suffix . :
> IP Address. . . . . . . . . . . . : 0.0.0.0
> Subnet Mask . . . . . . . . . . . : 0.0.0.0
> Default Gateway . . . . . . . . . :
>
> PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
> Connection-specific DNS Suffix . :
> IP Address. . . . . . . . . . . . : 118.101.50.219
> Subnet Mask . . . . . . . . . . . : 255.255.255.255
> Default Gateway . . . . . . . . . : 118.101.50.219
>
>
> D:\>ipconfig/renew
>
> Windows IP Configuration
>
> Ethernet adapter Local Area Connection:
>
> Connection-specific DNS Suffix . :
> IP Address. . . . . . . . . . . . : 192.168.1.3
> Subnet Mask . . . . . . . . . . . : 255.255.255.0
> Default Gateway . . . . . . . . . : 192.168.1.1
>
> PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
> Connection-specific DNS Suffix . :
> IP Address. . . . . . . . . . . . : 118.101.50.219
> Subnet Mask . . . . . . . . . . . : 255.255.255.255
> Default Gateway . . . . . . . . . : 118.101.50.219
>
> D:\>ipconfig/all
>
> Windows IP Configuration
>
> Host Name . . . . . . . . . . . . : MetalShaving
> Primary Dns Suffix . . . . . . . :
> Node Type . . . . . . . . . . . . : Unknown
> IP Routing Enabled. . . . . . . . : No
> WINS Proxy Enabled. . . . . . . . : No
>
> Ethernet adapter Local Area Connection:
> Connection-specific DNS Suffix . :
> Description . . . . . . . . . . . : VIA Compatable Fast
> Ethernet Adapter #2
> Physical Address. . . . . . . . . : 00-E0-4D-32-CE-8F
> Dhcp Enabled. . . . . . . . . . . : Yes
> Autoconfiguration Enabled . . . . : Yes
> IP Address. . . . . . . . . . . . : 192.168.1.3
> Subnet Mask . . . . . . . . . . . : 255.255.255.0
> Default Gateway . . . . . . . . . : 192.168.1.1
> DHCP Server . . . . . . . . . . . : 192.168.1.1
> DNS Servers . . . . . . . . . . . : 192.168.1.1
> Lease Obtained. . . . . . . . . . : Wednesday, October 22,
> 2008 11:33:36 PM
> Lease Expires . . . . . . . . . . : Friday, November 21,
> 2008 11:33:36 PM
>
> PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
> Connection-specific DNS Suffix . :
> Description . . . . . . . . . . . : WAN (PPP/SLIP) Interface
> Physical Address. . . . . . . . . : 00-53-45-00-00-00
> Dhcp Enabled. . . . . . . . . . . : No
> IP Address. . . . . . . . . . . . : 118.101.50.219
> Subnet Mask . . . . . . . . . . . : 255.255.255.255
> Default Gateway . . . . . . . . . : 118.101.50.219
> DNS Servers . . . . . . . . . . . : 202.188.0.133
> 202.188.1.5
>
>
> Test #2:
>
>
> D:\>ipconfig/flushdns
>
> Windows IP Configuration
> Successfully flushed the DNS Resolver Cache.
>
> D:\>ipconfig/release
>
> Windows IP Configuration
>
>
> Ethernet adapter Local Area Connection:
> Connection-specific DNS Suffix . :
> IP Address. . . . . . . . . . . . : 0.0.0.0
> Subnet Mask . . . . . . . . . . . : 0.0.0.0
> Default Gateway . . . . . . . . . :
>
> PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
> Connection-specific DNS Suffix . :
> IP Address. . . . . . . . . . . . : 118.101.50.219
> Subnet Mask . . . . . . . . . . . : 255.255.255.255
> Default Gateway . . . . . . . . . : 118.101.50.219
>
>
> D:\>ipconfig/renew
>
> Windows IP Configuration
>
> Ethernet adapter Local Area Connection:
>
> Connection-specific DNS Suffix . :
> IP Address. . . . . . . . . . . . : 192.168.1.3
> Subnet Mask . . . . . . . . . . . : 255.255.255.0
> Default Gateway . . . . . . . . . : 192.168.1.1
>
> PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
> Connection-specific DNS Suffix . :
> IP Address. . . . . . . . . . . . : 118.101.50.219
> Subnet Mask . . . . . . . . . . . : 255.255.255.255
> Default Gateway . . . . . . . . . : 118.101.50.219
>
> D:\>ipconfig/all
>
> Windows IP Configuration
>
> Host Name . . . . . . . . . . . . : MetalShaving
> Primary Dns Suffix . . . . . . . :
> Node Type . . . . . . . . . . . . : Unknown
> IP Routing Enabled. . . . . . . . : No
> WINS Proxy Enabled. . . . . . . . : No
>
> Ethernet adapter Local Area Connection:
> Connection-specific DNS Suffix . :
> Description . . . . . . . . . . . : VIA Compatable Fast
> Ethernet Adapter #2
> Physical Address. . . . . . . . . : 00-E0-4D-32-CE-8F
> Dhcp Enabled. . . . . . . . . . . : Yes
> Autoconfiguration Enabled . . . . : Yes
> IP Address. . . . . . . . . . . . : 192.168.1.3
> Subnet Mask . . . . . . . . . . . : 255.255.255.0
> Default Gateway . . . . . . . . . : 192.168.1.1
> DHCP Server . . . . . . . . . . . : 192.168.1.1
> DNS Servers . . . . . . . . . . . : 192.168.1.1
> Lease Obtained. . . . . . . . . . : Wednesday, October 22,
> 2008 11:58:36 PM
> Lease Expires . . . . . . . . . . : Friday, November 21,
> 2008 11:58:36 PM
>
> PPP adapter {9552DD77-E324-4E85-B801-1C1B61CACEF1}:
> Connection-specific DNS Suffix . :
> Description . . . . . . . . . . . : WAN (PPP/SLIP) Interface
> Physical Address. . . . . . . . . : 00-53-45-00-00-00
> Dhcp Enabled. . . . . . . . . . . : No
> IP Address. . . . . . . . . . . . : 118.101.50.219
> Subnet Mask . . . . . . . . . . . : 255.255.255.255
> Default Gateway . . . . . . . . . : 118.101.50.219
> DNS Servers . . . . . . . . . . . : 202.188.0.133
> 202.188.1.5



 
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John Wunderlich
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Posts: n/a
 
      23rd Oct 2008
Penang <(E-Mail Removed)> wrote in news:bbdc21c9-126b-4da5-b4fd-
(E-Mail Removed):

> I've tested IPConfig /flushdns command and found out that it doesn't
> work. But before I go on, here are some background details...
>
>


You have a misunderstanding on how "flushdns" works. When connecting
to a site, a DNS lookup is made to find the IP address of that site.
After obtaining this information, that result is cached in a local
memory so that if you need to look up the same address in the near
future, you have it locally and don't have to go out to the DNS server
to look it up again.

Flushdns simply clears out this local DNS cache and forces the next
lookup to go to the DNS server to get its answer. You can't tell if it
worked by doing an "ipconfig" command.

-- John
 
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Gregg Hill
Guest
Posts: n/a
 
      23rd Oct 2008
You CAN tell if it worked:

To see the effect of a /flushdns, do the following at a command prompt:

ipconfig /displaydns

That will display your current DNS cache.

ipconfig /flushdns

Flushes the cache.

ipconfig /displaydns

Displays the cleared cache.



"John Wunderlich" <(E-Mail Removed)> wrote in message
news:Xns9B407DEDFFC56wunderpsdrscray@138.126.254.210...
> Penang <(E-Mail Removed)> wrote in news:bbdc21c9-126b-4da5-b4fd-
> (E-Mail Removed):
>
>> I've tested IPConfig /flushdns command and found out that it doesn't
>> work. But before I go on, here are some background details...
>>
>>

>
> You have a misunderstanding on how "flushdns" works. When connecting
> to a site, a DNS lookup is made to find the IP address of that site.
> After obtaining this information, that result is cached in a local
> memory so that if you need to look up the same address in the near
> future, you have it locally and don't have to go out to the DNS server
> to look it up again.
>
> Flushdns simply clears out this local DNS cache and forces the next
> lookup to go to the DNS server to get its answer. You can't tell if it
> worked by doing an "ipconfig" command.
>
> -- John



 
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RickMerrill
Guest
Posts: n/a
 
      23rd Oct 2008
John Wunderlich wrote:
> Penang <(E-Mail Removed)> wrote in news:bbdc21c9-126b-4da5-b4fd-
> (E-Mail Removed):
>
>> I've tested IPConfig /flushdns command and found out that it doesn't
>> work. But before I go on, here are some background details...
>>
>>

>
> You have a misunderstanding on how "flushdns" works. When connecting
> to a site, a DNS lookup is made to find the IP address of that site.
> After obtaining this information, that result is cached in a local
> memory so that if you need to look up the same address in the near
> future, you have it locally and don't have to go out to the DNS server
> to look it up again.


Right on.

> Flushdns simply clears out this local DNS cache and forces the next
> lookup to go to the DNS server to get its answer. You can't tell if it
> worked by doing an "ipconfig" command.
>
> -- John


Actually, you can tell if 'flushdns' worked by doing
ipconfig /displaydns
and it should only show two entrys.

 
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PA Bear [MS MVP]
Guest
Posts: n/a
 
      23rd Oct 2008
Why in the world did you crosspost this to Win98 General Discussion?

Penang wrote:
> Hi, all !
>
> I've tested IPConfig /flushdns command and found out that it doesn't
> work. But before I go on, here are some background details...

<snip>
 
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Bruce Chambers
Guest
Posts: n/a
 
      24th Oct 2008
Penang wrote:
> Hi, all !
>
> I've tested IPConfig /flushdns command and found out that it doesn't
> work. But before I go on, here are some background details...
>
> My connection to the net is via ADSL, dynamic link. In theory, the use
> of the following 3 commands:-
>
> ipconfig /flushdns
> ipconfig /release
> ipconfig /renew
>
> supposed to flush out the "old" dns, and obtain a "new" one.
>
> So I made a batch file (ip.bat) with the following command:-
>
> ipconfig /flushdns
> ipconfig /release
> ipconfig /renew
> ipconfig /all
>
> and run 2 tests, about 20 minutes apart.
>
> The result is, the dns and the IPs stayed the same !!
>
> The IP for test #1 is 118.101.50.219, so is test #2 !
>
> I wonder if I have done something wrong. If I do, please tell me.
>



If you want to ensure a new IP Address (with which the "\flushdns"
switch has *nothing* to do) you'll need to reboot the computer after
using the "/release" command. (It's also normal practice to reboot
after using the "\flushdns" command, as well.)


--

Bruce Chambers

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