OCI: X Display prereq

To avoid getting an error ‘can’t open display’ when running ssh -X <compute>, or when getting some error with the oraInstaller, solution is to install the following packages:

yum install xorg-x11-xauth xorg-x11-fonts-* xorg-x11-font-utils xorg-x11-fonts-Type1 xdpyinfo

If not enough, check the following values in /etc/ssh/sshd_config:

X11Forwarding yes
X11DisplayOffset 10
X11UseLocalhost no

Then restart the ssh service:

systemctl restart sshd.service (OL7)

Optionally, on OL7, install the following prereq packages for OL7:

yum install compat-libcap1 libstdc++-devel ksh glibc-devel libaio-devel psmisc

Another option is to setup a full desktop as documented into this document.