The software described in this documentation is either in Extended Support or Sustaining Support. See https://www.oracle.com/us/support/library/enterprise-linux-support-policies-069172.pdf for more information.
Oracle recommends that you upgrade the software described by this documentation as soon as possible.

2.2.40 Unable to Register with ULN After First Reboot

Following the first reboot after installing Oracle Linux 6, you are prompted to register your system with ULN. If you did not configure your network during the installation, the registration process to ULN cannot succeed. To register your system, log in as root, configure the system's network manually, and run uln_register.