Year 2015 Mainframe z13

Its been long time I don't write a post in my blog . I came back to my blog after I found google result on  IBM Mainframe MCL which I need a quick info why customer need to update their MCL .

A recommendation PE as below

MCL Recommendations

• Apply and activate MCLs AT LEAST once a quarter
• Download MCLs to Removable Media (keep SUL media current)
• Use AROM/SUL when MCL apply would be disruptive
• If performing a POR/IML in the same window, wait until after all MCL activity is complete.
• Combine MCL activity with other activity (MES/Service/Reconfiguration)

Advantages

• Fewer unique LIC images to support
• Shorter download and install/activate times
• Reduced exposure to problems fixed in non-activated MCLs
• Emergency fixes can be supplied more expeditiously

source from MCLTRS