Linux - NetworkingThis forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.
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I have som problems with my Wlan connection which is described in another thread in the wireless forum. But I suspect that a part of the problem is not wlan related, just network (TCP/IP) related. I have a IBM T42 Thinkpad running Debian Sarge with Kernel 2.6.10.
When i get my Wlan card to work. I can ping my local router, log on to it with a browser, use "nslookup" and the "host" command on WAN addresses. However i cannot ping URL's or WAN Ip-adresses. It says: "Network not availiable"
Part of the the /etc/network/interfaces looks like
Since I am connected to my router and can use nslookup and host there must be some other problem. If a use the wired connection (eth0) which have an identical configuration apart from the IP-address and the Wlan stuff it works fine.
What's your router ?
Since you can connect to the router, do some query dns, it seems to me that you're 192.168.0.0/24 LAN is well configured.
But you cannot access to any other network... so, to my mind, either there's a firewall in your router that forbids the WLAN to communicate with others network, or there's a problem in your router's routing table.
I am not very good at Linux networking yet, but since google is my friend I have made some discoveries which I believe points out the problem. I read about routing tables and did following.
I brought up eth1 (my Wlan interface), ran the command "route -n" and got this output:
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface MSS Window irtt
192.168.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 0 0 0
Then i brought eth1 down, brought eth0 (gigabit Ethernet card) up and ran the same command with this output:
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface MSS Window irtt
192.168.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 0 0 0
0.0.0.0 192.168.0.1 0.0.0.0 UG 0 0 0 eth0 0 0 0
I have figured out that IP 0.0.0.0 means "the rest of the world" aka WAN. And that entry is not present in the eth1 table which means (correct me if I am wrong) Ip-packets with an address outside my LAN (192.168.0.0) will not be routed...
Is this supposed to be some kind of common knowledge I have missed out? I thought it would be enough to just fill in the correct entrys (default GW) in the /etc/network/interfaces file.
I guess I can figure out the command for adding the correct entry, but if someone know it, please share that information.
yes that's it... the command is
route add default gw 192.168.0.1
you're right about what it means... but what's queer is that the gateway should be configured thanks to the "gateway 192.168.0.1" entry in your /etc/network/interfaces file...
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