Hi Everyone, My name is Phil. I am currently taking a networking class for my computer system managment degree. In our class we are supposed to go and find forums in the IT catagory so that is why I am here. I am supposed to ask a question to the forum also. Here is my question. This is a recent problem I had setting up a POS system for a new resturant. I have also had this problem in the past. The network I was installing the system on to was a DHCP Network. The POS's were setup manually configured with a static IP address. In the router that was acting as the DHCP Server I configured static leases. This was a 2 station POS. Once I got the router configured correctly the 2 stations could talk to each other but they were unable to browse to the web, but once I changed them from manual configuration to DHCP there were able to. My question is why can they not get to the internet when they are manually configure but they can when they are DHCP. I have had this same problem in the past on the network were I work. If the discription of the system doesnt make sense or you have question let me know

Thanks Phil.

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Assuming I'm reading your question right...

It depends on the service and the modem. If your modem has DHCP built in or your ISP assigns multiple IP addresses then it's probably a matter of imporper configuration. If your ISP doesn't do this then you need DHCP on your router to assign share the connection. There may be a way to manually configure it to share the connection without DHCP (I don't think so, but I'm not 100% sure) in which case you're back to not having the proper settings.

What it really comes down to is that your average ISP gives you one IP adress, if DHCP is off then there's nothing to translate packages coming to your external IP to the right local system.

I have IP cameras on my networks that are configured with static IPs. However, the IP addresses I use are outside the router's dhcp IP address pool and everything works great. If I let the cameras use a dhcp address, the camera software would have to be changed each time the router was rebooted.

It accually had nothing to do with the ISP. I see I left out some info though. The system was setup with a comcast cable modem with a netgear wireless router connected to it. I had a laptop working off of the wireless with no problem but when I tried the POS's the would not go out to the internet but they could talk to each other.

When you don't have DHCP set up ONE system will connect to the internet, I don't know how that one system is chosen, probably by the lowest IP address. You should be able to enable DHCP and simply change the routers port-range to include the cameras, you can then assign static IPs to them using the routers control page. This is just how it works, you need to have DHCP somewhere on your network, if it's not on the router you'd have to have a dedicated DHCP server (or another router) before the primary router.

When you don't have DHCP set up ONE system will connect to the internet, I don't know how that one system is chosen, probably by the lowest IP address. You should be able to enable DHCP and simply change the routers port-range to include the cameras, you can then assign static IPs to them using the routers control page. This is just how it works, you need to have DHCP somewhere on your network, if it's not on the router you'd have to have a dedicated DHCP server (or another router) before the primary router.

There are no cameras in the network in question. Static IPs should be outside the dhcp ip pool.

It sounds like you didn't set the gateway on the POS.

Is there any particular need to use static IP's? I would just let DHCP take care of it and let the objects on your network ARP to their little mechanical hearts content.

It sounds like you didn't set the gateway on the POS.

BINGO!! This was my first thought.

Do an ipconfig /all on your computers and compare the data from them.

Are they all in the same subnet? (i.e 192.168.x.x - One may be 192.168.y.x)

Make sure that the DHCP assigned addresses have the correct Gateway AND DNS settings being assigned from the DHCP server. If you cant access the internet but CAN see the other computers, make sure you can PING the gateway. And make sure the settings are uniform for all computers (DHCP assigned or Statically assigned) Did I spell that right? LOL
-Me

commented: Actual knowledge. +2

It sounds like you didn't set the gateway on the POS.

This.

Sounds like a missing Gateway or missing DNS servers when manually configured.

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