In patching SharePoint, prior to the August 2012 CU (wow, that’s a long time ago), patches had to be applied sequentially as a matched pair. First Foundation, then Server. As of August 2012 CU, there’s a single patch. If you have SP2010 Server, just apply that one CU. Note the 2012 CUs assume SP1 is already installed.
Note: I would not apply a CU unless the last SharePoint Config Wizard ran successfully. That can be seen in Central Admin under Upgrade/Patch Status. The one exception is a farm with a known existing problem running a successful Config Wizard session, in which case a CU is a rational approach to solving this, as long as you have a server snapshot and a full DB Server backup (all SharePoint DBs) to roll back to in case the CU doesn’t solve the Config Wizard session issue. The place to start for Config failures is the log. After any Config Wizard run a log is produced. This log provides (too much) detail. The place in the log to look is the first “ERROR” text.
Sometimes the Registry on a server gets out of sync with the products in the Farm Config DB. Here’s how to very quickly and safely sync them:
Sometimes the CU will complain that the expected version is not found. You can force this to occur, by telling the CU to bypass the detection of correct software, but do so at your own risk:
After applying the CU, a reboot is required. The process tells you as much at the end. However on reboot it doesn’t tell you you need to run the Config Wizard. here’s how:
From command line, you can always trigger a Config Wizard session using:
psconfig -cmd upgrade -inplace b2b -wait
More thorough is this command:
psconfig -cmd upgrade -inplace b2b -force -cmd applicationcontent -install -cmd installfeatures
August 2012 CU installs clean, but sometimes the bypass detection is needed. Spot testing indicates faster performance in the browswer, and lower RAM utilization when compared against SP1 + June 2011 CU.