Hello Martin,

DR>> In addition to the excellent advice, you should upgrade and reboot
DR>> before taking your next backup.

MG> Errm, I think you meant "upgrade and reboot AFTER taking your next
MG> backup".

Yes, I thougt the same.
But much better is to do both, backup before AND after an upgrade,
ofcourse on different media ;-).
Then you have more security and possible strategies to choose from when
differences occur.

MG> If this is a full backup, done with something like rsync, it pretty much
MG> guarantees that none of your stuff will be lost if the upgrade breaks
MG> something vital *and* that restoring the backup will leave you with a
MG> runnable system.

You can also use the SDCard copier from Rasbian Jessie and Stretch to make 100
% exact copies of a good working SDCard of the same size, with the help of a
USB (micro) SDcard reader/writer.

Once a year I download a complete new version of Raspbian and use a self made
textfile: Personalize.txt to implement many settings and software downloads to
my wish, and not to forget one etc.
Ofcourse I immediate change that text file if there are new settings or
software installed for the next new SDcard.
I think this a more safe strategy then continuesly updating and upgrading.
Upgrading from Raspbian Wheezy to Jessy did not give the same result als
DownLoading a new Jessie from the original distributor.
So for bigger upgrades choose to use a complete new version,
especially when also upgrading hardware, i.e. from Pi 2B to 3B,
or from Pi 3B to 3B+ etc.
The old version often does not work on a newer machine,
but the other way round, the newer often also works on the older models.
That way installing new versions after march 14 each year is the most wise
strategy there is.
Or if you are always running the same software on the same hardware year after
year, and do not need new features, you could stay on that same version without
updating. I.e. for a dedicated continues task for instance.
But after some time security of card wear could be a beginning problem.
That's where you have BackUps for ;-).
Webbrowsers are one of the fast changing software packages I presume.
Good Luck in rebooting.

Henri.

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