Changing subnets on a Home LAN

[Bob S]

I use XP (SP3 MCE) and have a home LAN using a Linksys BEFSR41 router with 4
wired ports fed by a cable modem. I also work from home and have software
installed on my desktop to use a VPN in conjunction with my work. Every day
I have a bat file run (through scheduled tasks) to copy my data to my wife's
computer and her data to my desktop (for backup purposes). All of this
copying is, of course, done over the LAN. Unfortunately, I have to
disconnect my VPN to do so, because the computers cannot see each other over
the LAN whenever my desktop has the VPN running. Fortunately, my VPN
(Cisco) has a feature that can be checked to "allow local LAN access", which
I have now checked. But the computers still cannot see each other. I have
found out that the reason is that I need to "set up my LAN so that my
machine's IP address is one of 3 subnets listed below.
192.168.214.0/24 192.168.215.0/24 192.168.216.0/24 "

I need your help in doing this. I have several questions.

1. Do I change these things on my router or in Win XP?

2. I think it is in Win XP. If so, is it in the dialog box for Network
Connections/properties/Internet Protocol (TCP/IP)/Properties?

3. If the answer to #2 was "Yes", do I do this for my normal "Local Area
Connection" or for the one connected to my VPN? The normal Local Area
Connection has selected (in that dialog box) "Obtain an IP address
automatically" and "Obtain DNS server address automatically". But the Local
Area Connection for the VPN has specific IP addresses for IP address, subnet
mask, default gateway, preferred DNS server, and Alternate DNS server.

Can anyone give me guidance here?

Thanks in advance.

Bob

 

[John Wunderlich]

I use XP (SP3 MCE) and have a home LAN using a Linksys BEFSR41
router with 4 wired ports fed by a cable modem. I also work from
home and have software installed on my desktop to use a VPN in
conjunction with my work. Every day I have a bat file run
(through scheduled tasks) to copy my data to my wife's computer
and her data to my desktop (for backup purposes). All of this
copying is, of course, done over the LAN. Unfortunately, I have
to disconnect my VPN to do so, because the computers cannot see
each other over the LAN whenever my desktop has the VPN running.
Fortunately, my VPN (Cisco) has a feature that can be checked to
"allow local LAN access", which I have now checked. But the
computers still cannot see each other. I have found out that the
reason is that I need to "set up my LAN so that my machine's IP
address is one of 3 subnets listed below. 192.168.214.0/24
192.168.215.0/24 192.168.216.0/24 "

I need your help in doing this. I have several questions.

1. Do I change these things on my router or in Win XP?

2. I think it is in Win XP. If so, is it in the dialog box for
Network Connections/properties/Internet Protocol
(TCP/IP)/Properties?

3. If the answer to #2 was "Yes", do I do this for my normal
"Local Area Connection" or for the one connected to my VPN? The
normal Local Area Connection has selected (in that dialog box)
"Obtain an IP address automatically" and "Obtain DNS server
address automatically". But the Local Area Connection for the VPN
has specific IP addresses for IP address, subnet mask, default
gateway, preferred DNS server, and Alternate DNS server.

Can anyone give me guidance here?

In a normal home environment, Windows is set up to use DHCP to
automatically configure the network addresses. These network addresses
come from a DHCP Server which is usually your router. So to change the
subnet, you need to connect to your Router's configuration page and
change the router's LAN IP address to be in one of those subnets (e.g.
192.168.215.1). This is a tricky manoever because as soon as you
change the address of the router, you will no longer be able to
communicate with it until your computer switches over to that subnet as
well. (a "repair" on the Windows network connection should do it).

HTH,
John

 

[Bob S]

Thank you John. I have a further question.
On my Router web configuration page, I have 6 rows of 4 boxes each, as
follows.
Specify an IP address
Subnet Address
Default Gateway Address
DNS (Required) 1
DNS (Required) 2
DNS (Required) 3


Do I put the values 192 168 215 1 into the first, second or third row,
or some combination of those?
Do I enter anything into the DNS rows?

I did find the place to click "repair" when I need that.

Thanks again for your former help and thanks in advance for your answers to
these questions.
Bob

 

[smlunatick]

Thank you John.  I have a further question.
On my Router web configuration page, I have 6 rows of 4 boxes each, as
follows.
Specify an IP address
Subnet Address
Default Gateway Address
DNS (Required) 1
DNS (Required) 2
DNS (Required) 3

Do I put the values 192  168  215  1   into the first, second or third row,
or some combination of those?
Do I enter anything into the DNS rows?

I did find the place to click "repair" when I need that.

Thanks again for your former help and thanks in advance for your answers to
these questions.
Bob

Before doing anything, your VPN access is currently working so you
need to look your current LAN IP address first, on both your PC and
the laptop. Disconnect the VPN and then

-- Start
-- Run
-- enter cmd
-- at the ">" prompt; enter ipconfig

Look for IP address under ".... Local Area Connect" on both PCs.

The IP addresses should both have the same IP scheme "192.168.xxx"
with the "forth" "column" having different numbers.

Once this is confirmed, check the anti-virus / firewall softwares.

 

[John Wunderlich]

Thank you John. I have a further question.
On my Router web configuration page, I have 6 rows of 4 boxes
each, as follows.
Specify an IP address
Subnet Address
Default Gateway Address
DNS (Required) 1
DNS (Required) 2
DNS (Required) 3


Do I put the values 192 168 215 1 into the first, second or
third row, or some combination of those?
Do I enter anything into the DNS rows?

I did find the place to click "repair" when I need that.

Thanks again for your former help and thanks in advance for your
answers to these questions.
Bob

Make sure this is the Router LAN configuration and not the WAN
configuration... Then...

IP Address = 192 168 215 1
Subnet Address = 192 168 215 0
Default Gateway = 192 168 215 1

Usually a "Subnet Mask" is asked for rather than a "Subnet Address"..
if this really is a Subnet Mask, then it should be 255 255 255 0.

Usually DNS is obtained from the WAN side, but you might want to look
at your current configuration and see what's there and copy it.

-- John

 

[Bob S]

Thank you John. It was "Subnet Mask" as you suspected. I am sorry for the
confusion with saying "Subnet Address".
Bob