ICS in combination with a Broadband Router in 1 LAN

[Davy]

Hello,

I'm hosting a small network with 20 PC's (most of them XP), with 1 broadband
router and 1 switch. All the PC's are connected to the switch, and the
switch is connected to the router.
The router assings IP's by DHCP.

The problem is :
* When 1 of the PC's accidently enables ICS (Internet Connection Sharing),
the compete LAN fails to operate. (time-outs, PC's not found anymore, ...).
Is it Possible to Enable ICS in LAN, in combination with another Gateway
(broadband router) ?
A possible cause of this problem could be the fact that I used 27.0.0.*
for the "private" IP, assigned by Dhcp.
I'll change this to 10.0.0.*, wich is compiant the standards. Maybe
this will already solve the problem.

Can anybody explain me why the ICS in combination with another gateway is
causing me a lot of troubles ?

Another question :
* Has anybody a fine script to use, for solving most of the troubles in a
Workgroup? (like disabling firewalls, ICS, setting a standard workgroup,
setting a standard PCname, ... )

Thanks.

Davy

 

[Chuck]

Hello,

I'm hosting a small network with 20 PC's (most of them XP), with 1 broadband
router and 1 switch. All the PC's are connected to the switch, and the
switch is connected to the router.
The router assings IP's by DHCP.

The problem is :
* When 1 of the PC's accidently enables ICS (Internet Connection Sharing),
the compete LAN fails to operate. (time-outs, PC's not found anymore, ...).
Is it Possible to Enable ICS in LAN, in combination with another Gateway
(broadband router) ?
A possible cause of this problem could be the fact that I used 27.0.0.*
for the "private" IP, assigned by Dhcp.
I'll change this to 10.0.0.*, wich is compiant the standards. Maybe
this will already solve the problem.

Can anybody explain me why the ICS in combination with another gateway is
causing me a lot of troubles ?

Another question :
* Has anybody a fine script to use, for solving most of the troubles in a
Workgroup? (like disabling firewalls, ICS, setting a standard workgroup,
setting a standard PCname, ... )

Thanks.

Davy

Davy,

ICS is a software based NAT router, includes its own DHCP server, and assigns
addresses on the 192.168.0.0/24 subnet.

You can't have ICS on the same network as a NAT router, if the router has DHCP
enabled. If you do, you will have chaos - some computers will get DHCP settings
from the ICS server, others from the router. This will leave you with 2
subnets, as I suspect you are experiencing.

--
Cheers,
Chuck
Paranoia comes from experience - and is not necessarily a bad thing.
My email is AT DOT
actual address pchuck sonic net.

 

[Robert L [MS-MVP]]

quoted from http://www.howtonetworking.com/casestudy.htm

Don't enable ICS on a LAN with a router as DHCP



Situation: A small network with a Linksys router connecting to the Internet. The router is also DHCP server to assign IP to all computers. Recently, they create ICS on one of computer. It messes up the whole network.



Cause: ICS can be a DHCP server and also it auto assigns IP 192.168.0.x.



Resolution: 1. That doesn't make sense to add an ICS on a LAN with router and DHCP server.

2. If for reasons, you do need to use ICS to separate the network as two LANs, the outside NIC IP should be in the range of the outside LAN IP and inside LAN should be 192.168.0.0/24.



For more and other information, go to http://howtonetworking.com.

Don't send e-mail or reply to me except you need consulting services. Posting on MS newsgroup will benefit all readers and you may get more help.

Bob Lin, MS-MVP, MCSE & CNE
How to Setup Windows, Network, Remote Access on http://www.HowToNetworking.com
Networking, Internet, Routing, VPN Troubleshooting on http://www.ChicagoTech.net
This posting is provided "AS IS" with no warranties.
I recommend Brinkster for web hosting!

Hello,

I'm hosting a small network with 20 PC's (most of them XP), with 1 broadband
router and 1 switch. All the PC's are connected to the switch, and the
switch is connected to the router.
The router assings IP's by DHCP.

The problem is :
* When 1 of the PC's accidently enables ICS (Internet Connection Sharing),
the compete LAN fails to operate. (time-outs, PC's not found anymore, ....).
Is it Possible to Enable ICS in LAN, in combination with another Gateway
(broadband router) ?
A possible cause of this problem could be the fact that I used 27.0.0.*
for the "private" IP, assigned by Dhcp.
I'll change this to 10.0.0.*, wich is compiant the standards. Maybe
this will already solve the problem.

Can anybody explain me why the ICS in combination with another gateway is
causing me a lot of troubles ?

Another question :
* Has anybody a fine script to use, for solving most of the troubles in a
Workgroup? (like disabling firewalls, ICS, setting a standard workgroup,
setting a standard PCname, ... )

Thanks.

Davy