up2date fails

[yoloits]

I was running up2date from a command line and it was pulling down the
packages.  The it stopped with the error that it failed because of a DNS
error.
The problem is now when I run up2date it says the system is fully updated
even though it is not.  I can check versions of some installed packages and
see that some are not updated.  Redhat's network management site shows the
system as not updated.

How can I get update to work correctly?

Thanks,
Jay