is there a way to see network usage on command line
 

i would like to monitor network traffic usage on red hat servers
is there a way to do this on the command line i.e. something like the top command

Look into "ntop"

Try iftop:

http://ex-parrot.com/~pdw/iftop/

some alternatives would be iptraf that comes packaged with RedHat, or ethereal.

You could also try ssh into the RH server and just using netstat to see what's comming in and going out