I have a Suse linux box behind a linksys router that's plugged in to my DSL box. I also have a windows machine plugged into the linksys router. i can network between the windows and linux machine and i can get to the internet through both but the linux box is just incredibly slow for web browsing. it pings www.google.com and various sites just fine. But if you bring up google or any other site in a web browser (mozilla or konqueror) it can have really long lag times or just time out.

I posted about this before and someone suggested putting the linksys router address as my gateway on the linux machine. I did that and now the time outs hardly every occur but it's still very sluggish. If I plug my linux machine directly into the DSL box then it works great.

What else should I look at? Any ideas anyone?

Are you sure you have the correct DNS servers set on the Linux machine? Take a look at the DNS server settings on the Windows machine and make sure you have the same thing on the Linux machine.

I'm using DHCP on both machines.

Have you checked the DNS server addresses? There are settings that can be made in Linux that can prevent it from getting the DNS server addresses from the DHCP server.

Can you explain in more detail please.

when i look at ifconfig the IP address the machine gets is 192.168.100.1

the nameservers adress it gets by DHCP. You want me to set that manually? to what? and why?

thanks

well, resolving domain names is something that can frequently take a long time, and there can be significant differences between asking your router to resolve a name, and asking verizon's nameserver directly. that's why you should check to see which nameserver your windows box is using, and compare it to the nameserver your linux box is using. if they're the same you can eliminate this and try something else. but it's also possible they are not the same, and that's where your problem lies.

so...in windows: find the icon for the LAN in the system tray (bottom right corner) and double click it. then click the support tab, and the details button. several DNS servers should be listed. write them down, post them here.

in linux: cat /etc/resolv.conf and post the output.

The result of ipconfig /ALL on my windows machine says the DNS servers are 192.168.0.1 and 205.171.3.65

My linux machine has the same in /etc/resolv.conf

search domain.actdsltmp
nameserver 192.168.0.1
nameserver 205.171.3.65

There's still a remote possibility that there is come kind of compatability issue between the Linux box and the DNS forwarding taking place on the Linksys router but it's highly unlikely.

I think the next thing I'd check is the MTU size. If you look at the output of the ifconfig command on your Linux box, it should list the MTU size. In any of the Linksys routers I've worked with, there is a place where you can set the MTU size. Make sure the MTU size on the Linksys router is the same as or larger than the MTU size on the Linux machine. Then try it.

If that doesn't help, I think I'd hand edit the /etc/resolv.conf file on the Linux machine and remove the Linksys router as the DNS server. Just try using the outside DNS server. You won't need to reboot after you edit the file. See if that makes a difference.

when you connected directly to the modem and experienced a noticable difference in performance, did you change the ethernet cable? it's possible the cable itself is defective (i've had this happen seemingly overnight, where my connection went from being fine to almost unusable, and a simple cable swap fixed the problem).

hmm. as an experiment, try pinging various sites using their ip addresses, and then ping them using their domain name, and see if there's a difference. ie, compare

ping www.google.com
ping 66.102.7104

ping www.linuxquestions.org
ping 64.179.4.149

and see if there's any difference. i believe the nameserver is only queried if you type in the name, so if there's a problem with the DNS server the ip pings should be faster right? i don't know, i'm struggling to think of what your problem could be.

well i hand edited /etc/resolv.conf and took out the 192.168.0.1 (note that 192.168.0.1 is the DSL box and 192.168.1.1 is the linksys router - is that right?)

anyway, the same things happened. long time to load pages. pinging is reasonably fast even if i type www.google.com - pinging the ip address instead of the hostname does not produce output noticably faster.

The MTU on my linux machine is set to 1500. I tried 1492 with the same effects (i restarted eth0 after i made those changes).

I don't know how to set the MTU on my linksys router. I got to the admin page but i didn't see any settings for MTU (i have the blue 4 port befrs41 linksys router). Are you sure this model has that setting? anyone have any idea how to change that setting?

I know this is a pain - I really appreciate everyone's effort so far.

i dont know, i've never even considered the DSL modem itself....i assume that's what you're talkign about right? try putting 192.168.1.1 in resolv.conf and see if that helps (i can't imagine a modem acting as a nameserver, whereas the router probably does. so confirm 192.168.1.1 is your router, and try it out in resolv.conf)

I've used the befrs41 and befrs81 routers in the past. It seems to me they both had a place where you could change the MTU size. Check all the configuration pages to see if you can find it. I know the configuration pages were different for each of them so maybe it was just the befrs81.

I'm with mcd. I find it very odd that both your dsl modem and your Linksys router both have private IP addresses. How do you have your Linksys router set up, just to use a static IP address or is it actually getting an IP address on the WAN port from the DSL modem?

Is the dsl modem one of those Westell modem/router combination devices? If it is, it should already have a firewall built in to it. Perhaps the Linksys befrs41 is a device you don't need on your network. You might get buy with just using a switch to connect all of your PCs to the modem.

Why are you trying to resolve DNS requests to the Linksys or the DSL modem? I'm not sure this works and all that will happen is that you will we waiting for a timeout to then try the real server. The best that the Router or modem could do is proxy the request to the real DNS servers youve got configured. As both boxes can see the real DNS servers directly cut out the middle man.

You say your PC is using 192.168.100.1 while your router is 192.168.1.1. If the mask is 255.255.255.0 then these are on different subnets and I'm surprised it works at all.

All 3 devices should have an address in the same subnet. This means that any of the digits masked with 255 the network number should be the same. So by default on the linksys all devices should use 192.168.1.x.

So lets say the linksys is 192.168.1.1 255.255.255.0 You then need to assign a DHCP range on it of say 192.168.1.10 to 192,.168.1.20.

Also in the DHCP config you need to assign 192.168.1.1 as your default gateway and 205.171.3.65 as your nameserver.

Both PC's should now pick up this info via dhcp and it should all work.

Cheers

Pete

Sorry Pete, do i feel like an idiot - i mistyped that IP address - the ip address of my XP and Linux machines are 192.168.1.100 and .101 - you're right i don't think it would work otherwise.

mcd and conwanrl, you're right the linksys router address is statically set to 192.168.1.1 - that is the way it was when i bought it. I could change it on the admin page but i have to change it to something specific. there is no option to get it from the DSL modem.

I don't think my modem is a modem/router combo. it says nothing about that in the booklet for the device.

ok, so make sure that route -n lists 192.168.1.1 as your gateway, and try /etc/resolv.conf with this:

search domain.actdsltmp
nameserver 192.168.1.1
nameserver 205.171.3.65

see if that makes a difference. the reason i suggest trying your router as a nameserver first is that (i believe) most linksys routers act as cached nameservers by default, so it can *sometimes* speed up name resolution. but baldy is probably right, that you'd be better off removing 192.168.1.1 from resolv.conf. it's a small change though, so my advice is try both and see what happens.

also, do you have a firewall? i had some trouble with name resolution because i was blocking outbound traffic, iirc i had to open udp port 53 or something. but i had different symptoms, i think all connections just timed out.