Just to drive the system administrator nuts, for some reason Redhat sysctl parameters by default are not robust enough to handle starting up even a small application server. There are several cases on My Oracle Support that explain how to set the variables but at a minimum I found this to a good starting point:

fs.file-max = 65536
kernel.msgmni = 512
kernel.msgmax = 1048576
kernel.msgmnb = 1048576
kernel.shmmni = 4096
kernel.shmmax = 33554432
kernel.sem = 250 256000 64 1024

You can add/modify these entries in the sysctl.conf file (/etc/sysctl.conf). Once they are modified you can put them into effect by issuing sysctl -p. If you want to do a change temporarily you can issue: sysctl -w parameter=value.