Hello. I have been trying to install ros in debian jessie and I remain unsuccessful. I am not able to run the "sudo -E apt-key adv --keyserver hkp://pool.sks-keyservers.net:80 --recv-key 0xB01FA116". Can you please help me ?

It gives me an error "Host not found" when I run it. I also tried running the command without the port number but to no vain. In one post I read that it would help to rerun the command after sometime. But it has been 2 days and I am nowhere able to run this command. Can you please help me ? Is there a workaround for this problem ? Thank you