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-   -   tcpdump says no device found? (http://www.linuxquestions.org/questions/linux-software-2/tcpdump-says-no-device-found-830002/)

raypsi 09-02-2010 03:57 PM

tcpdump says no device found?
 
I looked and have tcpdump installed on ubuntu 10.04 lts I can do a tcpdump --help and it gives the commands.
I get no device found when I do tcpdump from the terminal window.

my Ubuntu is having trouble looking up domains it just sits there and hangs looking up google.com

I'm on a ATT 3mb DSL dry line running an asus netbook and a biostar via mobo desktop they both have trouble looking up domains right out of the DSL modem.

I would try to set the DNS in ubuntu but I don't know how to do that without knowing the gateway and such. I have to get the IP of the computer, the netmask, the gateway, and the DNS for the manual setup.

quanta 09-02-2010 10:47 PM

Quote:

Originally Posted by raypsi (Post 4086322)
I looked and have tcpdump installed on ubuntu 10.04 lts I can do a tcpdump --help and it gives the commands.
I get no device found when I do tcpdump from the terminal window.

What exactly command did you use?
Quote:

Originally Posted by raypsi (Post 4086322)
my Ubuntu is having trouble looking up domains it just sits there and hangs looking up google.com

I'm on a ATT 3mb DSL dry line running an asus netbook and a biostar via mobo desktop they both have trouble looking up domains right out of the DSL modem.

I would try to set the DNS in ubuntu but I don't know how to do that without knowing the gateway and such. I have to get the IP of the computer, the netmask, the gateway, and the DNS for the manual setup.

echo "nameserver 8.8.8.8" >> /etc/resolv.conf
echo "nameserver 8.8.4.4" >> /etc/resolv.conf

ghostdog74 09-02-2010 11:03 PM

how many interfaces do you have. there's a switch in tcpdump to specify interfaces. check the man page.

raypsi 09-03-2010 05:35 AM

Quote:

Originally Posted by ghostdog74 (Post 4086620)
how many interfaces do you have. there's a switch in tcpdump to specify interfaces. check the man page.

Yes had to do: sudo tcpdump -i eth0

I didn't see the interface switch -i the first time around. It was right there in tcpdump --help

Thanks


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