Help setting IP settings, two NICs (Full Version)

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Tmark86 -> Help setting IP settings, two NICs (30.Jun.2008 2:55:57 PM)

I am just getting into ISA server for the first time and have been reading and learning alot about it. I want to use the server to host several web servers, exchange, sharepoint and also possibly act as the firewall. This will be added to our local domain.

The network configuration is as follows. Internet comes in via cable and connects to a Cable Modem. Then from there, into our current VPN router. (VPN will be taken over by ISA eventually.) From the router into a 16 port switch and out to the various computers and other switches.

What I am having trouble with is configuring the internal and external IPs of the network cards for the ISA server. It currently has 2 NIC cards installed and I could add a third if neccessary. We have a static IP address from our internet host Comcast.

The static IP from comcast is 75.145.178.165  The router's IP is 192.168.3.1 Then all computers are 192.168.3.*    The DNS server is 192.168.3.2    What I don't know is first whether I should put the ISA server between the modem and the router or between the router and the switches.  Secondly, depending on where I put it, what do the external and internal IP addresses need to be.    

From what I have learned, I setup the external between the modem and router with 75.145.178.165 as the IP, 255.255.255.0 as the subnet and 75.145.178.166 as the defaut gateway. This didn't seem to work. I also know that there are no DNS entries for the external NIC and no default gateway for the internal with the internal DNS pointing to our DNS server internally.  Other than this I haven't really been able to get the external connected.

Just wondering if anyone out there could possibly help me out. Thanks in advance for any help.



paulo.oliveira -> RE: Help setting IP settings, two NICs (30.Jun.2008 5:28:31 PM)

Hi,

quote:

The static IP from comcast is 75.145.178.165  The router's IP is 192.168.3.1 Then all computers are 192.168.3.*    The DNS server is 192.168.3.2    What I don't know is first whether I should put the ISA server between the modem and the router or between the router and the switches.  Secondly, depending on where I put it, what do the external and internal IP addresses need to be.

Whatīs comcast? Is it the modem? Why do you need the router, is it your DHCP server?
quote:

From what I have learned, I setup the external between the modem and router with 75.145.178.165 as the IP, 255.255.255.0 as the subnet and 75.145.178.166 as the defaut gateway. This didn't seem to work. I also know that there are no DNS entries for the external NIC and no default gateway for the internal with the internal DNS pointing to our DNS server internally.  Other than this I haven't really been able to get the external connected.

Just to make this info clear to me.
Is 75.145.178.165 the IP of external ISA interface? Is 75.145.178.166 the IP of the modem?
Configure an IP address for internal ISA NIC in the same subnet as your router/internal clients.

Regards,
Paulo Oliveira.



Tmark86 -> RE: Help setting IP settings, two NICs (30.Jun.2008 5:47:22 PM)

Thanks Pualo for the response. Comcast is our ISP. We have a SMC cable modem from them. The router then serves as the VPN client and also to give internet access to numerous computers. It is also currently serving as our DHCP server as well. The router can be eliminated if that is neccessary. It is the way it is setup now but can be changed.

75.145.178.165 is the public IP address assigned to us by our ISP. Currently we have public DNS forwarding our domain name to that IP address. I can change those public DNS records to forward to another IP if neccessary too.

The router is a linksys VPN router. The modem I am not able to login to and is an SMC something. I have complete control over the router configuration. The router is IP address 192.168.3.1 and that is set as the default gateway of all computers currently. Its subnet is 255.255.255.0  The internal DNS is 192.168.3.2 on the same subnet as the router. I believe that the internal NIC should be 192.168.3.* subnet 255.255.255.0 with no default gateway and the internal DNS as 192.168.3.2     I set it up that way and think that is correct. I can't test until I can setup the external NIC as well.
Also on the Linksys router is a DMZ port that says that it will forward all ports to the specified address. I don't know if this should or could be used.

I don't know what the settings are supposed to be for the external nic in the ISA server. Should they correspond to our Public IP address assigned by the ISP or to the IP addresses given by the Router?
In the Linksys router, the setup information looks like this and this is where I got the 75.145.178.166.

Linksys  WAN settings - Static IP Address   75.145.178.165
             Subnet Mask -                                255.255.255.0
             Default Gateway Address -             75.145.178.166
             DNS Servers -                                *.*.*.*



paulo.oliveira -> RE: Help setting IP settings, two NICs (1.Jul.2008 3:44:37 PM)

Hi,

quote:

75.145.178.165 is the public IP address assigned to us by our ISP. Currently we have public DNS forwarding our domain name to that IP address. I can change those public DNS records to forward to another IP if neccessary too.

Why isnīt you public DNS server responsable for the external DNS queries, once you have a private DNS server. Make your private DNS server forward the DNS queries to your public DNS server.
quote:

The router is a linksys VPN router. The modem I am not able to login to and is an SMC something. I have complete control over the router configuration. The router is IP address 192.168.3.1 and that is set as the default gateway of all computers currently. Its subnet is 255.255.255.0  The internal DNS is 192.168.3.2 on the same subnet as the router. I believe that the internal NIC should be 192.168.3.* subnet 255.255.255.0 with no default gateway and the internal DNS as 192.168.3.2     I set it up that way and think that is correct.

OK, this is the rigth configuration.
quote:

Also on the Linksys router is a DMZ port that says that it will forward all ports to the specified address. I don't know if this should or could be used.

Letīs not use it now. Maybe you can configure later. Letīs focus on make your internet work with ISA server.
quote:

I don't know what the settings are supposed to be for the external nic in the ISA server. Should they correspond to our Public IP address assigned by the ISP or to the IP addresses given by the Router?
In the Linksys router, the setup information looks like this and this is where I got the 75.145.178.166.

Copy the router NIC configuration to ISA external NIC. This will be fine:
WAN settings - Static IP Address   75.145.178.165
             Subnet Mask -                                255.255.255.0
             Default Gateway Address -             75.145.178.166
             DNS Servers -                                *.*.*.* (none)
Put ISA server between the modem and the Linksys router.

Regards,
Paulo Oliveira.



Petervs -> RE: Help setting IP settings, two NICs (22.Jul.2008 3:40:22 AM)

Hi Everyone i actually have a similar problem, and i am hoping you can help me.
i am a newbie am trying to wrap my head around the installation and configuration of Isa 2006 STD. Specifically the Network address setup
ok let me start
Layout
ISA 2006 STD with 2 Nic's 
Template Edge Firewall
I have a router with a static ip from my ISP 196.212.23.220
which is the address of the one nic (external)
my (internal) ip address range is 172.16.1.0-172.16.1.255
my ISA Box is 172.16.1.10 ===> on my clients i am setting this as my default gateway

When it asks me for internal network addresses do i choose the nic or put in the ip address range?
reason why i ask is it seems to attach every address i.e
0.0.0.1 -126.255.255.255, 128.0.0.0-196.212.23.215 etc when i chose the Internal nic.
and is that correct then ?
im not sure if i understand Microsoft's version of internal network setup :)
i think i might be blocking access somewhere

So before i do the installation i have internet access
i do the installation and i get denied access to everything even on the box
i add the allow unrestricted access in the rules but still i get nothing
i cant ping anyone externally

and i messing something up ?
thanks for your help!



paulo.oliveira -> RE: Help setting IP settings, two NICs (22.Jul.2008 7:28:45 AM)

Hi,

what you should do is: configure the IP address of the external NIC in the same network as your router with the default gateway pointing to your routerīs IP address.

In the internal NIC, configure the IP address of the internal network in the same subnet as your internal clients, set no default gateway and set and internal DNS.

In the internal network definition, you should put only the networks behind ISA trust interface.

Create access rules according to your needs.

Regards,
Paulo Oliveira.



Petervs -> RE: Help setting IP settings, two NICs (22.Jul.2008 9:48:44 AM)

Thanks Paulo your advice worked!



paulo.oliveira -> RE: Help setting IP settings, two NICs (22.Jul.2008 9:56:27 AM)

Hi,

glad to hear it!! Thanks for follow up!! [:D]

Regards,
Paulo Oliveira.



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