Re: Unable to recovery due missing wal_file

Not sure that would have mattered for the reasons below.

You might want to take a look at the below:

https://www.postgresql.org/docs/9.5/static/wal.html

In particular:

https://www.postgresql.org/docs/9.5/static/wal-intro.html

Short version WAL files are essential to restoring and on the originating server are recycled, subject to the configuration parameters explained here:

https://www.postgresql.org/docs/9.5/static/wal-configuration.html

So the wal archiving you have set up is not storing everything, it removes older files over time?