redhat8.0 and cable internet

[coolzero16]

I can't establish an internet connection between my cable modem and redhat 8.0 i have tried realtek8139 and a com card...both are supposed to be very well supported. the setup was all dhcp.

what are some different ways to test the internet connection to see maybe where the problem is?

 

[LuckyTaxi]

see if you can ping yourself. Try these commands

"ping 127.0.0.1"

"ifconfig" --> did it give you an IP address?

Link on your NIC?

 

[Mucho]

One thing to keep in mind is some Cable ISP require you to release your ip whenever you change a NIC and then renew it.

 

[coolzero16]

release my ip...is that something that needs to be done in windows or linux?

 

[topaz22]

pinging 127.0.0.1 won't really help you, it would ping yourself on the loopback device, not the ethernet device.
if you do a ifconfig -a, you should see if your eth0/1/2... and check to see if your device is there, with an ip address.

also check lsmod to see if the 8139too module is loaded.

what is meant by releasing your ip is just power cycling the modem every time the nic is changed.

depending on your modem, you may be able to use a web brower to check the diagnostics.. i believe some motorola modems use http://192.168.100.1/ as the url of the mini web server in the modem.

 

[Barnaby W. Füi]

Originally posted by: topaz22
i believe some motorola modems use http://192.168.100.1/ as the url of the mini web server in the modem.

haha! thats f@*ing amazing! you rock

damn this thing has a page which shows a log of events and everything. the latest 50 or so have *****'s for a timestamp though, i wonder how/why it lost the time...

edit: ah i was assuming the opposite order. the older ones have ***'s for timestamps. this thing is freaking cool, i am getting some cool ideas as far as monitoring it remotely....

 

[mindwarp]

I am using a 8139 card with timewarner cable with absolutely 0 issues. Post the output of /sbin/ifconfig -a along with /sbin/netstat -ar

 

[coolzero16]

no inet addresss shows up whatsoever when i do ifconfig -a. it skips directly from

eth0 Link encap:Ethernet HWaddr.....
UP BROADCAST RUNNING MULTICAST MTU:1500....

im assuming between those two lines up above there is supposed to be an inet address correct?



also, it says no such file or directory when i try /sbin/netstat -ar

 

[mindwarp]

ok well I cant remember its specific location (netstat), but try either /sbin/dhclient eth0, or /usr/sbin/dhclient eth0

 

[RockyMaivia]

Have you tried re-booting the cable modem?

 

[topaz22]

im assuming between those two lines up above there is supposed to be an inet address correct?

correct.

try 'ifdown eth0' and then 'ifup eth0' and that should have some sort of dhcp message, if it hangs there, then there's some problem with the modem assigning a ip to the nic that it is hooked up to. if it goes quickly, check ifconfig to see if there is an ip address.

check out /etc/sysconfig/network-scripts/ifcfg-eth0
there should be a line that says BOOTPROTO="dhcp"
i believe there is a tool in redhat called netconf or netconfig that you can run, not sure.

did you try to connect to the modem with a browser?

 

[coolzero16]

try 'ifdown eth0' and then 'ifup eth0' and that should have some sort of dhcp message, if it hangs there, then there's some problem with the modem assigning a ip to the nic that it is hooked up to. if it goes quickly, check ifconfig to see if there is an ip address.

alrighty ill go try that...also gonna try and re-reboot the cable modem. maybe the first time i did it i did not leave it unplugged long enuf? im gonna call midcontinent and sound pissed off so maybe they'll give me an honest anwser when i ask them if they bind to mac adresses.

ill let u know how it goes

 

[coolzero16]

mkay i called midco again and the first guy it alked to said that I could not reset the cable modem..i called again and the second guy i talked to said HE could reset the cable modem (see how the first guy decieved me? i wish i knew where he lived) so apparently they havve to reset the cable modem otherewise it is bound to mac address permanately (this is to get you to use THEIR nics) i told them i never agreed to a stupid service agreement of using their nics and since i paid for the nic they provided me i could use whichever one i wanted and i also said i would be contacting proper authorties if he did not reset my cable modem......he reset it


however, my problem with trying to get internet connectiong sharing between windows and linux is not working...i know this is borderline networking question, but it does involve two OS's so im going to ask anyway and if u tell me to go to networking cuz u dont know any possible solutions to this dilemna then i will

heres what im trying to do

internet--->linux----hub---other windows computers
the connection stops between linux and the hub or linux and the other windows computers. i typed ifconfig and no inet adress came up for eth1 which means dhcp cannot assign an adress for some reason...any ideas?

also, i tried ifdown eth1 and ifup eth1 (eth1 is the connection thats not working now)
it says Determining IP information for eth1... failed.
^^that is the same message that shows up when my computer is booting





alllso, in redhat 8.0 under network configuration this is what it says under the DNS tab
Hostname: localhost.localdomain
Primary dns 24.220.0.10
Secondary dns: 24.220.0.11

Domain name
midco.net

 

[topaz22]

one problem at a time. get the linux box working with the cable modem, *then* work on the routing/NAT.

which ethernet device is connected to the cable modem, eth0 or eth1 ? the device hooked up to the hub should have a static ip, since it will be the gateway for the other machines (popular candidates: 192.168.x.1, 10.0.x.1).

 

[Grminalac]

Set eth1 as a static I.p. address. (assuming eth0 is connected to your cable modem) Use the address of eth1 as the gateway on the other computers. You will need to start an i.p. masq to allow linux to route the other machines to the internet. One of the easiest methods I have found is by using a easy program called guidedog available here GUIDEDOG Remember this will blow your connection wide open allowing anyone access. To control access install guarddog a great program that allows you to customise a firewall using ip tables. You can find guarddog here. GUARDDOG
Both programs are completely free.

Enjoy...

You could also use squid a proxy program installed by linux in order to share access as well.

 

[coolzero16]

the connection between linux and the cable modem is working..sorry i didnt clarify that well
the next step is to open up linux as a gateway..ill let u know how it goes

 

[coolzero16]

ok i reinstalled linux again cuz a friend of mine thought maybe i didnt have all the netowk packages installed the first time around

a direct connection called eth1 has been established between linux and my computer

eth0(the nic that will be used as the gateway) stll does not work

i downloaded guidedog and activated ip masq....it said it rerouted my ip tables or somethin like that but i still cannot activate eth0 from network configurations

no internet adress shows up for eth0 when i type ifconfig either

when i type route here is whhat i get
Destination Gateway Genmask Flags Metric Ref Use Iface
24.220.200.0 * 255.255.254.0 U 0 0 0 eth1
127.0.0.0 * 255.0.0.0 U 0 0 0 lo
default host-1-200-220- 0.0.0.0 UG 0 0 0 eth1


here is my question besides got any other ideas .......... is it possible that i HAVE to have eth0 up before guidedog will even consider using it as part of the ip masq?

 

[topaz22]

a direct connection called eth1 has been established between linux and my computer

24.220.200.0 * 255.255.254.0 U 0 0 0 eth1

what is the 24.220.200.0 subnet? i'm guessing that this is the ip assigned from the cable modem, since it in an internet routable address.... but you say its a "direct connection" between linux and your computer, which is unclear. is this a hub or a crossover cable?

i don't understand how, if this is your connection between two comptuers, that you're using a routable ip address.. and since your dns ip's are in the range, this must actually be your connection to the internet... you should be able to browse on the linux machine.

my guess is that eth1 is connected to the cablemodem. eth0 has not yet been configured, and you need to set an ip for eth0 to use for the internal subnet. since eth0 does not show up, i'm guessing that the kernel module has not been loaded, or modules.conf doesn't have an alias for it.

what kind of cards are eth0 and eth1 ? running lspci will tell you. (please post this info) also in modules.conf (post this too) , check for 'alias eth0 xxxxxxx' and 'alias eth1 xxxxxxx' , where the xxxxxxx's should be the name of the kernel modules associated with the net cards.

here is my question besides got any other ideas .......... is it possible that i HAVE to have eth0 up before guidedog will even consider using it as part of the ip masq?

yes, its a must. the device must be funtioning before you apply packet filtering rules on it.

 

[Grminalac]

Well, what you basically want to do is this. Lemme think red hat 8.0... There is a graphical tool but its a bit strange to use. Make sure both cards are activated on startup. The card you have plugged into the cable modem set up assign address by dhcp. Set the card going from the L box to the hub as a static ip. (i.e. This is the gateway the other computers will use.)

Once the cable modem works. Then use guidedog to configure routing. Once that is working secure the network by using guarddog.
If you are using the graphical tool to setup internet, do not setup using the cable modem setting as I think in RH8 it attempts to configure it as ppoe. Just configure it as a LAN with settings assigned via DHCP.




You might need to restart the network after chaning settings using RH8 graphical toos as their network configurator seems a bit flaky.

 

[coolzero16]

k so if i assign an ip from linux box to hub what kind of ip can i use? anything i pick inc class c???

also when you assign static ip's there are a few boxs to fill

ip address
subnet mask
gateway

do i need to make up my ip's for all of em or only ip address? if i choose my own ip address for the ip address box BUT not the other two (subnet and gateway) then where do i get that information from?

 

[Grminalac]

Well keeping routing relaively simple you can do this....

Linux machine eth1 address 192.168.0.1
netmask 255.255.255.0
gateway empty

other computers sharing internet 192.168.0.(a number between 2 and 255)
netmask 255.255.255.0
gateway 192.168.0.1

 

[coolzero16]

and u didnt mention eth0 becuz thats the one thats setup dhcp right?

also will i need to run guidedog after i set this up or no?

 

[topaz22]

and u didnt mention eth0 becuz thats the one thats setup dhcp right?

nonono, the way that your current setup has eth1 as dhcp(since it has the 24.x.x.x ip), and eth0 is the static ip

 

[Grminalac]

yeah eth0 is assigned an ip a gateway and a netmask from your cable modem, since it is a dynamically assigned from your ISP it can change from time to time. Don't worry it will be automatically assigned all the settings such as DNS.

Remember you will have to assign dns settings on your windows machines attached. (if you cannot remember your ISP's settings try 208.236.36.3)

 

[coolzero16]

so i have to mess with the DNS settings for windows machines id like to hook up...but i dont have to mess with DNS settings for the linux machine?

if that DNS address u told me to guess and try doesnt work is there anyway to find it or do i have to call ISP?

also, i have to hook more than one windows computer up to the net so will there be more than one DNS address or will it be all the same for every windows computer?