Hello,
I have a LAN with 3 computers, connected to a router.
I can ping from one computer to the other by IP addresses, but not by their names! Now the question is, why.
As the router works as DHCP server as well as DNS server, it should know the IP addresses and names of all computers, and commands like "ping jonnie" should work...
Any ideas for how to diagnose this? I've googled a whole day, but maybe it's even too simple for that

Btw computers are running fedora14 or Windows7, and are (by DHCP) automatically configured to use the router as DNS server.
The router is a Netgear WNR3500v2.
Just realized that the router only knows the name of one computer (the Windows7 one), but I'm also not able to ping this one by name.
I don't want to set up one of the computers as a DNS server, since their IP addresses are given dynamically by the router's DHCP. I think the cleanest solution should be the router itself doing the work, since it knows automatically about the dynamic IPs of all connected computers.

Huh.

After reading your post, I decided to see whether my OpenWRT wireless router (Belkin F5D8230-4 V1002) populates the DNS server with the machine names learned via DHCP, which I didn't really expect to be the case. Well, as it turns out, it does. I wouldn't expect that many SOHO devices to do that, however. Not sure why, I guess it is just from past experience where they didn't.

You'll have to look at your wireless device, and see if there is something in the configuration that allows you to inform it to do this. If not, you're going to have to look at another solution, or use 'hosts' files. The DHCP leases my systems attain never change the IP, so that wouldn't be a big deal in my environment. If yours do, you should consider static IP addresses, and use the 'hosts' files I mentioned. Your environment is small enough it's isn't an issue. I can't imagine needing to set up a DHCP server for three devices.

Well the thing is, we often have people visiting, or moving in or out of our apartment, so the machines are actually subject to change. And anyway it's always good to learn how to set up a system that works automatically.
Couldn't find any useful configuration option on my router's web interface. But it is a DHCP and DNS server and therefore should be able to do it, else it's very stupidly designed...
But right now it seems it only caches names of Windows machines (don't know why) and if asked for DNS service, it just forwards to the remote router of my ISP instead of handling the locally cached names as well.
Incredible how complicated such stuff is, it should be the most straightforward thing to do... Thanks in advance for any help

Most of your home routers that server DHCP are not DNS server but proxy's to the ISP DNS server. As they are not DNS server they will not update themselves with host that are using your router for DHCP. If you want a true DNS then you are going to have to setup you own DNS server to accept updates from your router's DHCP server.

That's possible? I'm thinking of running a little home server anyway... so if the home server would handle DNS and automatically uses the info of the DHCP of the router, then that'll work I think
Can you give me a brief idea of how to do it? Some parameter in some config file maybe?
Or any further ideas? Every help appreciated

Have a look at this THREAD.