Basic questions: Setting up static IPs for my network

[Ikonomi]

I recently got a new router, Linksys BEFSR41 V3, and it doesn't seem to like to maintain a steady DHCP table -- most of the time it shows up blank in the router configuration. On one PC, I use BitTorrent, and I would like to keep the 6881-6999 port range forwarded to the right computer.

The "network" is usually only 3 PCs, with a fourth laptop that drops in now and again.

But I've never done this before, and I'm clueless about networking stuff. I know how to set up a static IP in Windows, but... I guess I still have questions:

1. Can I have one PC with a static LAN IP and still have my router function as a DHCP server for the other computers on the network?

2. The little TCP/IP config window asks for preferred and alternate DNS server addresses. I can't find these on the SBC website, and I don't know how to (or if I can) get my computer to tell me the IP of the DNS server. What should I do?

Thanks for the help. I know this is really newbish stuff.

 

[ToeJam13]

it doesn't seem to like to maintain a steady DHCP table

DHCP typically does what's called a "first come, first serve" handout scheme. It starts at the beginning on its address range, and starts handing them out in asending order. If you have several machines, they'll get a different address every time if you boot them up in differing orders.

Some DHCP servers allow you to hand out a specific address to a specific client based on its MAC address. It makes it nice for people with laptops since they never have to change their settings between work and home - the network statically assigns an address for you. That said, the Linksys model you provided does not offer this feature.

1. Can I have one PC with a static LAN IP and still have my router function as a DHCP server for the other computers on the network?

Yes! Your Linksys router has a section in the DHCP menu labeled "Starting IP Address". Normally, this address is 192.168.1.2, since the Linksys itself is 192.168.1.1. However, if you raise that trailing number to something higher, you'll increase the range for clients with static addresses. Try something like 192.168.1.9. That way, the Linksys will start its DHCP range at 192.168.1.10 and higher.

The little TCP/IP config window asks for preferred and alternate DNS server addresses. I can't find these on the SBC website, and I don't know how to (or if I can) get my computer to tell me the IP of the DNS server.

If SBC dynamically assigns an IP address using DHCP, don't worry about this. When your Linksys makes a DHCP (dynamic host configuration protocol) query, your ISP responds with several items. Not only do you get an IP address, but also important items like your subnet mask, your default gateway IP address, and any IP addresses of DNS servers.

If SBC gave you a static IP address, things are different. If SBC sent you this info via email, try to find the message since your DNS servers IP addresses will most likely be in there to. If not, just call SBC Broadband and ask.

Whatever way you get it, your clients on the trusted home side of your router will most likely use the router's address itself (192.168.1.1) as their DNS server. DHCP clients get it assigned automatically, your static clients will have to have it punched in manually.

 

[Ikonomi]

Hey, thanks for your reply! You explained a lot. I'm going to set up a static IP for this computer when I get home from work... I'm glad to learn that the laptop can still DHCP it up when it comes home.

 

[howdyduty]

"Whatever way you get it, your clients on the trusted home side of your router will most likely use the router's address itself (192.168.1.1) as their DNS server."

Not sure about that^

With dhcp, the clients would get the dns address from the router. The router gets the dns address from the isp dhcp.