As a good DBA, I begin to be up to date with all Cumulative Update (CU) by my customers.
It is the first time that I run an update for SQL Server 2016 with the CU 3.
I download the CU on Microsoft website and I begin my patching campaign on all SQL server 2016 instances.

The first one is quick & successful.
The second one, with R Services, is a little bit different.
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After, the features’ selection, you need to accept the “R services download”.
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Servers are not able to go to Internet to download the R services package.
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A new step appears “Offline Installation of Microsoft R Open and Microsoft R Server” with 2 links reference to download 2 packages.
I advise you to download both. SRO_xxx is for Microsoft R Open and SRS_xxx is for Microsoft R Server. It is not necessary but I think, it is every time good to have all packages for a build.
After, you have just to copy the two cab files to your server and select the folder in the update window.
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The installation of the Cumulative Update continues like usual.
This link here, give you the list of the Microsoft R Open and Microsoft R Server per build. It’s a very useful link.

PS: I do not use the installation by Command-line but flags are explained on this website.

Nice patching to you!

To finish, I give you a little tips: In SQL  Server 2017, you will have the same to do with the Python language
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