Re: When I use DialUp and LAN at same time, I cannot access LAN.

From: Steve Winograd [MVP] (winograd_at_pobox.com)
Date: 01/28/05 

Date: Fri, 28 Jan 2005 06:48:24 -0700

In article <1106901926.993116.133260@z14g2000cwz.googlegroups.com>,
davinderkumar@gmail.com wrote:
>Hello,
>
>I am on my company LAN network (DHCP). When I connect my machine to ISP
>then I cannot access any machine, any local company website.
>
>Configurations are as followins:
>
>C:\>ipconfig/all
>
>Ethernet adapter Local Area Connection:
>IP Address. . . . . . . . . . . . : 10.91.194.159
>Subnet Mask . . . . . . . . . . . : 255.255.255.0
>Default Gateway . . . . . . . . . : 10.91.194.1
>DHCP Server . . . . . . . . . . . : 10.91.0.33
>DNS Servers . . . . . . . . . . . : 10.91.0.33
>10.91.0.44
>10.91.0.11
>Primary WINS Server . . . . . . . : 10.91.0.16
>Secondary WINS Server . . . . . . : 10.91.202.10
>
>PPP adapter MYISP:
>
>Connection-specific DNS Suffix . :
>Description . . . . . . . . . . . : WAN (PPP/SLIP) Interface
>Physical Address. . . . . . . . . : 00-53-45-00-00-00
>Dhcp Enabled. . . . . . . . . . . : No
>IP Address. . . . . . . . . . . . : 10.148.8.82
>Subnet Mask . . . . . . . . . . . : 255.255.255.255
>Default Gateway . . . . . . . . . : 10.148.8.82
>DNS Servers . . . . . . . . . . . : 202.56.230.5
>202.56.230.6
>
>In DIALIP -> TCPIP Properties -> General Tab : Use dafault gateway on
>network is CHECKED. If I uncheck this then I cannot access internet.
>
>C:\>route print
>=================================================
>Active Routes:
>Network Destination Netmask Gateway Interface
>Metric
>0.0.0.0 0.0.0.0 10.91.194.1 10.91.194.159 21
>0.0.0.0 0.0.0.0 10.148.8.82 10.148.8.82 1
>10.6.6.6 255.255.255.255 10.148.8.82 10.148.8.82 1
>10.91.194.0 255.255.255.0 10.91.194.159 10.91.194.159 20
>10.91.194.159 255.255.255.255 127.0.0.1 127.0.0.1 20
>10.91.255.255 255.255.255.255 10.91.194.1 10.91.194.159 1
>10.148.8.82 255.255.255.255 127.0.0.1 127.0.0.1 50
>10.255.255.255 255.255.255.255 10.91.194.159 10.91.194.159 20
>10.255.255.255 255.255.255.255 10.148.8.82 10.148.8.82 50
>127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1
>224.0.0.0 240.0.0.0 10.91.194.159 10.91.194.159 20
>224.0.0.0 240.0.0.0 10.148.8.82 10.148.8.82 1
>255.255.255.255 255.255.255.255 10.91.194.159 10.91.194.159 1
>255.255.255.255 255.255.255.255 10.148.8.82 10.148.8.82 1
>Default Gateway: 10.148.8.82
>==================================================
>
>In this scenario, PING doesnt work as DNS servers are inaccessible.
>Please let me know any possible solution.
>
>Thanks,
>Davinder

Your computer's LAN IP address is in the 10.91.194.x subnet. The
LAN's DNS servers are in a different subnet: 10.91.0.x. Therefore,
the only way to communicate with them is through the default gateway.
However, when you dial into the ISP, the dial-up default gateway
overrides the LAN default gateway, preventing access to the LAN's DNS
servers.

Changing your computer's LAN subnet mask from 255.255.255.0 to
255.255.0.0 might fix everything, since all 10.91.x.x addresses
(including the DNS and WINS servers) would be in the same subnet as
your computer.

I strongly recommend consulting with your company's network
administrators before making any change yourself, for these reasons:

1. They're the ones who know how the network works and how it should
be configured.

2. They can tell you whether company policy allows making a dial-up
connection while connected to the LAN. That can be a security risk,
and some companies don't allow it. 

-- 
Best Wishes,
Steve Winograd, MS-MVP (Windows Networking)
Please post any reply as a follow-up message in the news group
for everyone to see.  I'm sorry, but I don't answer questions
addressed directly to me in E-mail or news groups.
Microsoft Most Valuable Professional Program
http://mvp.support.microsoft.com

Relevant Pages

  • Re: When I use DialUp and LAN at same time, I cannot access LAN.
    ... >>network is CHECKED. ... PING doesnt work as DNS servers are inaccessible. ... > Your computer's LAN IP address is in the 10.91.194.x subnet. ... > overrides the LAN default gateway, preventing access to the LAN's DNS ...
    (microsoft.public.windowsxp.network_web)
  • Re: LAN IP addresses
    ... some operating systems that the lowest and highest _subnet_ were ... "outside", you probably have no idea what mask may be used on the LAN, ... and I believe it should not matter to any network equipement either. ...
    (comp.os.linux.networking)
  • Re: Detecting host in the local network
    ... LAN. ... To send a frame to host at the other IP network you must send to ... router, if they're willing to respond to the ping and the router allows ARP ... address you specify for any sort of IP traffic is not on your local subnet ...
    (microsoft.public.windowsce.embedded)
  • Re: Is it possible to use wireless AND still access my LAN?
    ... The LAN and the wireless networks use different subnets. ... I assume so if multiple computers are allowed as a network. ... Assign them static IP addresses in a different subnet than your ...
    (microsoft.public.windowsxp.network_web)
  • Re: Loss of Connectivity on Only One PC on a LAN
    ... When you ran the Network Setup Wizard, ... The original setup of the LAN was done entirely by the user of the other PC on that LAN in July. ... I use a LAN connection which consists of two PCs each connected to a Linksys BEFSR 41 Router. ...
    (microsoft.public.windowsxp.network_web)