Upgrade from Postgres 9.3 to 9.5 I’m attempting my first upgrade of Postgres from 9.3 to 9.5. I’ve run into two roadblocks but not sure how to get around them. I have my 9.3 PGDATA set to /data/postgres, which is a separate filesystem on my RHEL 6 server. After installing 9.5 and running initdb, I attempted to run pg_upgrade using this command line:


/usr/pgsql-9.5/bin/pg_upgrade -b /usr/pgsql-9.3/bin -B /usr/pgsql-9.5/bin 
  -d /data/postgres -D /var/lib/pgsql/9.5/data --link -p 5432 -P 5433 -c


This command failed the link parameter test, because the 9.5 PGDATA value is not on the same filesystem as 9.3. Roadblock #1. 

I then tried to re-initialize 9.5 using this command:

initdb -D /data/postgres95


It errored saying "Data directory is not empty!". Roadblock #2. 

How do I proceed with this upgrade? I’d rather not move to a new server.
Self-answer from Kevin Struckhoff originally left as a comment:

Finally got back to this task and ran the upgrade successfully.

Turns out, since I use tablespaces in specific directories, the new 9.5 are right next to the old 9.3 dirs:


drwx------ 4 postgres postgres  4096 Oct  4  2014 PG_9.3_201306121
drwx------ 3 postgres postgres  4096 Apr 18 11:49 PG_9.5_201510051