While rlogged into a different UNIX machine, attempting to open ArcView or a graphics window in ArcInfo with the command 'display 9999' returns the error message:
"Cannot open channel to X server. Warning, the display service is not defined. Resetting to dumb terminal mode."
The xhost command has not been issued before rlogging into the second machine and 'setenv DISPLAY <hostname of first machine>:0.0' has not been set while rlogged into the second machine.
setenv DISPLAY <hostname of first machine>:0.0