Registering server issue: unable to get hardware information

Issue symptoms

Can not register the server with clnreg_ks, rhnreg_ks or during yum update. The error shown is similar to:

Profilename: server.hostname.com
An error has occurred:
Error communicating with server. The message was:
Internal Server Error
See /var/log/up2date for more information

Cause

The issue may be caused by collecting hardware information. The following might be found in /var/log/up2date:

Traceback (most recent call last):
  File "/usr/sbin/clnreg_ks", line 221, in <module>
    cli.run()
  File "/usr/share/rhn/up2date_client/rhncli.py", line 96, in run
    sys.exit(self.main() or 0)
  File "/usr/sbin/clnreg_ks", line 150, in main
    rhnreg.sendHardware(systemId, hardwareList)
  File "/usr/share/rhn/up2date_client/rhnreg.py", line 475, in sendHardware
    s.registration.add_hw_profile(systemId, _encode_characters(hardwareList))

Resolution

Skip checking for hardware in clnreg_ks or rhnreg_ks with --nohardware key.

Example:

clnreg_ks --nohardware