Hello i'm a teacher at a sec school in the UK, who has got fed up of the windows world and has changed my staff laptop (and seetting up a small lab) of linux machines.

Anyway I have been trying to get the my laptop to connect out of the network to the internet. the Mac using techs have been helping me and reserving me IP address and such like to help me, I have set up the Ip, subnet mask, gateway and DNS and am able to access the server 2003, file and printer servers (active directory?) infact have been very impressed which how well it has been doing

However i have completely faileded to get it to surf out to the web.

i have done a traceroute yahoo and it finds the Ip address from the DNS server then goes to the gateway but fails to get any further. the techs as i say use mac machines so i am fairly sure its not a a windows only thing. Also they have no idea why i cant connect (they have checked all my numbers .. ips etc) .... ideas anybody?

-yeasterday however it randomly for an afternoon connected (stoped again today). techs say they have not changed anything. but again today it is not able to get through..

You need to establish the ip address of the gateway to the internet connection. There will be a router or a computer that connects to the internet that does ip forwarding ( internet sharing). You need to know the ip address of this router/box or if it is running a dhcp server If it has a specific address (static addressing) then you add this to your network configuration as the gateway address. If it is running a dhcp server then you need to configure your system to pick up a lease (dhcp client) from the server. The techs should have all this info.

Got slightly further..

Checked in /etc/network/interfaces
and discovered that the network property is set to 10.12.51.0 as the gateway adrexx is 10.12.48,X this is obvoiuls wrong .... however cause i'm using a kanopix derivative (kanotix) it seems that if i change it to 10.12.48.0 it just recreates it when i boot.

How do i change it so it actually recognised that the gateway is part of the network?

Is the sysadmin using static addresses and can you be issued with one?

(as in Dear Techs

What is the DHCP settings across the network and what is the assigned IP address for the gateway (on your DHCP server?)

Also if the IP address is 10.12.XX.XX then tell the techs that the netmask should be 255.255.0.0 or similar (and not like 255.255.255.0 which would prevent you connecting)

the settings i have in my interfaces are as follows

address (static) 10.12.51.115
netmask = 255.255.252.0
network = 10.12.51.0
broadcast = 10.12.48.255
gateway = 10.12.48.1

Am not using dhcp, because all the dhcp address's go through an internall microsoft proxy, which only accepts connections from microsoft software.

Any thing else?

If config log =

traceroute to www.yahoo.akadns.net (216.109.117.106), 30 hops max, 38 byte packets
1 10.12.48.1 (10.12.48.1) 0.930 ms 0.961 ms 0.958 ms
2 * * *

Lengths@box:~$ ifconfig
eth0 Link encap:Ethernet HWaddr 00:0B:5D:4B:44:A2
inet addr:10.12.51.115 Bcast:10.12.48.255 Mask:255.255.252.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:3574 errors:0 dropped:0 overruns:0 frame:0
TX packets:121 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:299653 (292.6 KiB) TX bytes:18892 (18.4 KiB)
Interrupt:11

eth1 Link encap:Ethernet HWaddr 00:0E:35:1B:05:E3
inet addr:10.12.51.115 Bcast:10.12.48.255 Mask:255.255.252.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:2771 errors:0 dropped:0 overruns:0 frame:0
TX packets:635 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
Interrupt:11 Base address:0xe000 Memory:d0215000-d0215fff

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:8 errors:0 dropped:0 overruns:0 frame:0
TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:400 (400.0 b) TX bytes:400 (400.0 b)

Lengths@box:~$

Your address of 10.12.51.115 with a netmaks of 255.255.252.0 will see every IP address from 10.12.48.1 to 10.12.51.254, so the "gateway" setting appears to be valid, assuming there is a gateway at that IP address. The broadcast address is usually the top number in the range though, so it should be 10.12.51.255, not 10.12.48.255. With these settings, your network will be called the 10.12.48.0 network, not 10.12.51.0 network, I'm not sure what you were referring to with the network property question in the above post but I hope that clears up the confusion.

TCP/IP is really not a 'windows' or 'mac' or 'linux' thing, it is either set up right and works or it isn't. You did mention that the windows machines use a proxy to access The Internet, usually when setting up a network with a proxy server the direct web access (port 80 for http and possibly others) is blocked off so that the users have to go through the proxy to get out. This would explain why you can traceroute a website but can't open it in a web browser.

What it boils down to then is that you should try to set up your Linux browser to use the proxy to get to websites, it should be possible as proxy servers aren't usually so M$ specific that you can't get Linux to use it.

Sorry i confused the question a bit by adding on the information about the proxy server..

Ok in brief the issue with the proxy server is that the school both has an external proxy server (connected to via gateway 10.12.48.1) which can be accessed only by issud static IP address's. (such as the ip address i have been given of 10.12.51.115). - (proxy ip address = 213.249.157.48)

The School also has in internal proxy server (which is mostly used for controling software usage and student access. ) this proxy server is accessed by goin through the gateway at 10.12.48.10. It is setup using a very strickt microsoft only authentication method and as a result is immpossible to connect through (the dhcp automatically sets machines to go through this gateway)

Also i cant traceroute to the website, the traceroute gets to the gateway and then fails

1 10.12.48.1 (10.12.48.1) 0.930 ms 0.961 ms 0.958 ms
2 * * * ....
30 * * *

i know the DNS is correct because it picks up the Ip's on the traceroute from the DNS server.

I know the main Ip and such like is ok (at least i think i do) cause i can access my files from the netwrok server + i can print ... i just cant get it to connect to the internet