RHEL 5.4

[joliver@mdadb ~]$ sudo yum clean all
Loaded plugins: dellsysidplugin, rhnplugin
Cleaning up Everything
[joliver@mdadb ~]$ sudo yum update
Loaded plugins: dellsysidplugin, rhnplugin
Traceback (most recent call last):
File "/usr/bin/yum", line 29, in ?
yummain.user_main(sys.argv[1:], exit_code=True)
File "/usr/share/yum-cli/yummain.py", line 309, in user_main
errcode = main(args)
File "/usr/share/yum-cli/yummain.py", line 157, in main
base.getOptionsConfig(args)
File "/usr/share/yum-cli/cli.py", line 187, in getOptionsConfig
self.conf
File "/usr/lib/python2.4/site-packages/yum/__init__.py", line 664, in <lambda>
conf = property(fget=lambda self: self._getConfig(),
File "/usr/lib/python2.4/site-packages/yum/__init__.py", line 253, in _getConfig
self.plugins.run('init')
File "/usr/lib/python2.4/site-packages/yum/plugins.py", line 179, in run
func(conduitcls(self, self.base, conf, **kwargs))
File "/usr/lib/yum-plugins/rhnplugin.py", line 111, in init_hook
login_info = up2dateAuth.getLoginInfo()
File "/usr/share/rhn/up2date_client/up2dateAuth.py", line 217, in getLoginInfo
login()
File "/usr/share/rhn/up2date_client/up2dateAuth.py", line 184, in login
li = server.up2date.login(systemId)
File "/usr/share/rhn/up2date_client/rhnserver.py", line 64, in __call__
raise up2dateErrors.SSLCertificateVerifyFailedError()
up2date_client.up2dateErrors.SSLCertificateVerifyFailedError: The certificate is expired. Please ensure you have the correct certificate and your system time is correct.

Now I don't use RHEL, but all you've shown is that the YUM Python program raised an exception because your certificate expired.

So, what's your question? (May I presume that you do know that RHEL requires an annual subscription?)

You may absolutely so presume. The system in question has a valid entitlement. The certificate here almost certainly has nothing to do with that.

I "fixed" this by copying back the RPM database files I'd been having trouble with (this error came about because I moved them off and gave an rpm --rebuilddb) and fixed my original issue with some other hoodoo.

this is what you forgot to do AFTER running "yum clean all"
was this
see
" rpm --help " and " man rpm "

This error appears whether or not your are subscribed to RHN.

There's a fix on this page which worked for me:
http://kb.eclipseinc.com/kb/fix-rhn-certificate-errors/