FreeBSD upgrade 10.3 to 11.0

[B J]

On 11/25/16, James B. Byrne via freebsd-questions
<freebsd-questions at freebsd.org> wrote:
> I am testing out the procedures to upgrade our existing FreeBSD hosts
> from 10.3 to 11.0 using a bhyve guest configured for the purpose.  I
> have followed the instructions in the handbook/wiki to the best of my
> understanding. I have a question about the last step however.
>
> One is supposed to reinstall all of the port pkgs one has installed.
> Is there an automated way to do this provided by the FreeBSD
> community; or is this a case of roll your own script?

<snip>

I have two machines, each with two drives with FreeBSD.  I upgraded
all of those systems to 11.0 recently and encountered the same thing.
What finally worked for me was to upgrade the ports with:

portsnap fetch
portsnap extract
portsnap update

and the packages as well with:

pkg update
pkg upgrade

It seemed that if I didn't do it, the upgrading process would
overwrite or remove some of the files and libraries, resulting in
things like Mate and Slim not working properly after I was finished.

BMJ