docker - addressing environment variables used in parent image - postgresql

I need to create plpythonu extension on the postgres:10.3 image. For this, I extended the image with an installation command:
FROM postgres:10.3
RUN apt update && apt install -y postgresql-plpython-10
Now I need to run a psql command create extension plpythonu;. But at this point the postgres server is not running yet, so when running docker build . I get an error:
Step 3/3 : RUN psql -c "create extension plpythonu;";
---> Running in 037066c120ea
psql: could not connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"?
How do I fit this command in? And is there a way to do this without copypasting the entire docker-entrypoint.sh from the original postgres image? Maybe there's a way to specify this in docker-compose?

When step-2 is over you Postgres database down, that is why in Step-3 database is not running.
You can combine step-2 and step-3 together.
RUN apt update && \
apt install -y postgresql-plpython-10 && \
psql -c "create extension plpythonu;"
It means && (logical and) if previous commands successfully over then only execute next one.

Related

Postgres docker error: FATAL: password authentication failed for user

I created a Postgres container with docker
sudo docker run -d \
--name dev-postgres \
-e POSTGRES_PASSWORD=test \
-e POSTGRES_USER=test \
-v ${HOME}/someplace/:/var/lib/postgresql/data \
-p 666:5432 \
postgres
I give the Postgres instance test as a username and password as specified in the doc.
The Postgres port (5432) inside the container is linked to my 666 port on the host.
Now I want to try this out using psql
psql --host=localhost --port=666 --username=test
I'm prompted to enter the password for user test and after entering test, I get
psql: error: FATAL: password authentication failed for user "test"
There are different problems that can cause this
The version of Postgres on the host and the container might not be the same
If you have to change the docker version of Postgres used, make sure that the container with the new version is not crashing. Trying to change the version of Postgres while using the same directory for data might cause problem as the directory was initialized with the wrong version.
You can use docker logs [container name] to debug if it crashes
There might be a problem with the volumes used by docker (something with cached value preventing the creation of a new user when env variable change) if you changed the env parameters.
docker stop $(docker ps -qa) && docker system prune -af --volumes
If you have problem with some libraries that use Postgres, you might need to install some package to allow libraries to work with Postgres. Those two are the one Stack Overflow answers often reference.
sudo apt install libpq-dev postgresql-client
Other problems seem to relate to problems with docker configuration.

Configuration issue Postgres on Ubuntu?

I have installed Postgres 12 on Ubuntu by building it from source and I am facing two issues:
Although I followed the installation manual from Postgrez, every time I restart my computer, my Postgres server stopz and is no longer seen as a running process.
To start it the first time after install, I do this from the terminal:
/usr/local/pgsql/bin/initdb -D /usr/local/pgsql/data
/usr/local/pgsql/bin/pg_ctl -D /usr/local/pgsql/data -l logfile start
After a restart, to start DB again when I run: /usr/local/pgsql/bin/initdb -D /usr/local/pgsql/data, it throws this error:
initdb: error: directory "/usr/local/pgsql/data" exists but is not empty
If you want to create a new database system, either remove or empty
the directory "/usr/local/pgsql/data" or run initdb
with an argument other than "/usr/local/pgsql/data".
Does that mean that every time I start Postgres after a restart, I have to create a new /data directory?
Upon installing Postgres sing pip or pip3, one can just switch user to postgres and run psql to enter postgres, however now I have to run "/usr/local/bin/psql". Please note I have exported all the paths per https://www.postgresql.org/docs/12/installation.html. How can I fix this? Can an alias be set for this?
After a restart, to start DB again when I run:
/usr/local/pgsql/bin/initdb -D /usr/local/pgsql/data, it throws this
error:
Does that mean that every
time I start Postgres after a restart, I have to create a new /data
directory?
No, quite the opposite. You don't need to initdb after the first time, you just need to start. It is your attempt to initdb when you don't need to which is causing the error message. Note that attempting to initdb isn't doing any harm, because it refused to run. It just generates log/console noise.
Upon installing Postgres sing pip or pip3, one can just switch user to
postgres and run psql to enter postgres, however now I have to run
"/usr/local/bin/psql". Please note I have exported all the paths per
https://www.postgresql.org/docs/12/installation.html. How can I fix
this?
I don't know what your first sentence means, as you don't use pip or pip3 to install PostgreSQL (or at least, the docs don't describe doing so) although you might use them to install psycopg2 to enable python to talk to PostgreSQL.
You could use an alias, but it would probably make more sense to edit ~/.bash_profile to set the PATH, as described from the page you linked to under Environment Variables.
You have to register postgreSQL as a service.
run this:
pg_ctl register [-N servicename] [-U username] [-P password] [-D datadir] [-S a[uto] | d[emand] ] [-w] [-t seconds] [-s] [-o options]
Example:
pg_ctl register -N postgresql -U OS_username -P OS_password -D '/etc/postgresql/12/data' -w
More info in the manual: pg_ctl
Notes:
Username and Password is related to the OS, not postgresql
If you have doubts read the manual.
/usr/local/pgsql/bin/pg_ctl start -D '/usr/local/pgsql/data'
Export following in postgres user account's ~/.bashrc:
LD_LIBRARY_PATH=/usr/local/pgsql/lib
export LD_LIBRARY_PATH
PATH=/usr/local/pgsql/bin:$PATH
export PATH

Docker postgres doesn't start at build

I want do use a docker container to simulate my production environment, so I installed the db and the server in the same container, and not each in his own.
This is my dockerfile:
FROM debian
RUN apt update
RUN apt install postgresql-9.6 tomcat8 tomcat8-admin -y
RUN service postgresql start
RUN service postgresql status # says postgres is down
RUN su - postgres ;
RUN createdb db_example # fails !!!
RUN psql -c "CREATE USER springuser WITH PASSWORD 'test123';"
RUN exit
RUN service tomcat8 start
COPY target/App-1.0.war /var/lib/tomcat8/webapps/
CMD ["/bin/bash"]
The problem is that the database is down so I am uable to create the user and the database.
If I start the a debian docker container and do this steps per hand everything works fine.
Thanks for your help
All the recommendations in the comments are correct, it's better to keep services in different containers.
Nevertheless and just to let you know, the problem in the Dockerfile is that starting services in RUN statements is useless. For every line in the Dockerfile, docker creates a new image. For example RUN service postgresql start, it may start postgresql during docker build, but it doesn't persist in the final image. Only the filesystem persist from one step to another, not the processes.
Every process need to be started in the entrypoint, this is the only command that's called when you exec docker run:
FROM debian
RUN apt update
RUN apt install postgresql-9.6 tomcat8 tomcat8-admin -y
COPY target/App-1.0.war /var/lib/tomcat8/webapps/
ENTRYPOINT["/bin/bash", "-c", "service postgresql start && service postgresql status && createdb db_example && psql -c \"CREATE USER springuser WITH PASSWORD 'test123';\" && service tomcat8 start && sleep infinity"]
(It may have problems with quotes on psql command)
I have the problem hat in the war file the localhost for the database war hard coded.
Thanks to Light.G, he suggested me to use --net=host for the container, so now there is one container with the database and one with the tomcat server.
This are the steps I followed.
Build the docker image
docker build -t $USER/App .
Start a postgres database
We are using the host namespace it is not possible to run another programm on the post 5432.
Start the postgres container like this:
docker run -it --rm --net=host -e POSTGRES_USER='springuser' -e POSTGRES_DB='db_example' -e POSTGRES_PASSWORD='test123' postgres
Start the tomcat
Start the App container, with this command:
docker run -it --net=host --rm $USER/App

Postgres in Docker persistent data

I'm running postgres inside a docker container to limit the amount of system resources it has access to. I'm having some trouble understanding how to make the data persistent. I've read the following articles:
https://www.andreagrandi.it/2015/02/21/how-to-create-a-docker-image-for-postgresql-and-persist-data/
http://container42.com/2013/12/16/persistent-volumes-with-docker-container-as-volume-pattern/
Which suggest using a data only container, and then having my postgres container link to it. What I'm failing to understand is; what's the advantage to this? As far as I can tell, if for some reason the docker-machine shut down (for example; moving it to a different physical machine), the data only container stops running, and all of it's contents are lost? I've tried creating a volume in the postgres container, but it doesn't actually seem to save anything to the disk.
Here's my docker file. What am I doing wrong?
FROM ubuntu
MAINTAINER Andrew Broadbent <andrew.broadbent#manchester.ac.uk>
# Add the PostgreSQL PGP key to verify their Debian packages.
# It should be the same key as https://www.postgresql.org/media/keys/ACCC4CF8.asc
RUN apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys B97B0AFCAA1A47F044F244A07FCC7D46ACCC4CF8
# Add PostgreSQL's repository. It contains the most recent stable release
# of PostgreSQL, ``9.3``.
RUN echo "deb http://apt.postgresql.org/pub/repos/apt/ precise-pgdg main" > /etc/apt/sources.list.d/pgdg.list
# Install ``python-software-properties``, ``software-properties-common`` and PostgreSQL 9.3
# There are some warnings (in red) that show up during the build. You can hide
# them by prefixing each apt-get statement with DEBIAN_FRONTEND=noninteractive
RUN apt-get update && apt-get install -y python-software-properties software-properties-common postgresql-9.3 postgresql-client-9.3 postgresql-contrib-9.3
# Note: The official Debian and Ubuntu images automatically ``apt-get clean``
# after each ``apt-get``
# Run the rest of the commands as the ``postgres`` user created by the ``postgres-9.3`` package when it was ``apt-get installed``
USER postgres
# Create a PostgreSQL role named ``docker`` with ``docker`` as the password and
# then create a database `docker` owned by the ``docker`` role.
# Note: here we use ``&&\`` to run commands one after the other - the ``\``
# allows the RUN command to span multiple lines.
RUN /etc/init.d/postgresql start &&\
psql --command "CREATE USER docker WITH SUPERUSER PASSWORD 'docker';" &&\
createdb -O docker docker
# Complete configuration
USER root
RUN echo "host all all 0.0.0.0/0 md5" >> /etc/postgresql/9.3/main/pg_hba.conf
RUN echo "listen_addresses='*'" >> /etc/postgresql/9.3/main/postgresql.conf
# Expose the PostgreSQL port
EXPOSE 5432
# Add VOLUMEs to allow backup of config, logs and databases
RUN mkdir -p /var/run/postgresql && chown -R postgres /var/run/postgresql
VOLUME ["/etc/postgresql", "/var/log/postgresql", "/var/lib/postgresql"]
# Set the default command to run when starting the container
USER postgres
CMD ["/usr/lib/postgresql/9.3/bin/postgres", "-D", "/var/lib/postgresql/9.3/main", "-c", "config_file=/etc/postgresql/9.3/main/postgresql.conf"]
This one answers your question about data container:
docker mounting volumes on host
Regarding to your dockerfile, I would suggest you either:
1) use data container pattern
2) mount the volume to host machine by specifying: docker run -v [host-path]:[container-path] ..., so that data will be kept at one place in your host and will not be lost after the container is removed.
Ref: https://docs.docker.com/engine/tutorials/dockervolumes/#/mount-a-host-directory-as-a-data-volume

How to upgrade PostgreSQL from version 9.6 to version 10.1 without losing data? [closed]

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I'm using the PostgreSQL database for my Ruby on Rails application (on Mac OS X 10.9).
Are there any detailed instructions on how to upgrade PostgreSQL database?
I'm afraid I will destroy the data in the database or mess it up.
Assuming you've used home-brew to install and upgrade Postgres, you can perform the following steps.
Stop current Postgres server:
launchctl unload ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist
Initialize a new 10.1 database:
initdb /usr/local/var/postgres10.1 -E utf8
run pg_upgrade (note: change bin version if you're upgrading from something other than below):
pg_upgrade -v \
-d /usr/local/var/postgres \
-D /usr/local/var/postgres10.1 \
-b /usr/local/Cellar/postgresql/9.6.5/bin/ \
-B /usr/local/Cellar/postgresql/10.1/bin/
-v to enable verbose internal logging
-d the old database cluster configuration directory
-D the new database cluster configuration directory
-b the old PostgreSQL executable directory
-B the new PostgreSQL executable directory
Move new data into place:
cd /usr/local/var
mv postgres postgres9.6
mv postgres10.1 postgres
Restart Postgres:
launchctl load ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist
Check /usr/local/var/postgres/server.log for details and to make sure the new server started properly.
Finally, re-install the rails pg gem
gem uninstall pg
gem install pg
I suggest you take some time to read the PostgreSQL documentation to understand exactly what you're doing in the above steps to minimize frustrations.
Despite all answers above, here goes my 5 cents.
It works on any OS and from any-to-any postgres version.
Stop any running postgres instance;
Install the new version and start it; Check if you can connect to the new version as well;
Change old version's postgresql.conf -> port from 5432 to 5433;
Start the old version postgres instance;
Open a terminal and cd to the new version bin folder;
Run pg_dumpall -p 5433 -U <username> | psql -p 5432 -U <username>
Stop old postgres running instance;
Here is the solution for Ubuntu users
First we have to stop postgresql
sudo /etc/init.d/postgresql stop
Create a new file called /etc/apt/sources.list.d/pgdg.list and add below line
deb http://apt.postgresql.org/pub/repos/apt/ utopic-pgdg main
Follow below commands
wget -q -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add -
sudo apt-get update
sudo apt-get install postgresql-9.4
sudo pg_dropcluster --stop 9.4 main
sudo /etc/init.d/postgresql start
Now we have everything, just need to upgrade it as below
sudo pg_upgradecluster 9.3 main
sudo pg_dropcluster 9.3 main
That's it. Mostly upgraded cluster will run on port number 5433. Check it with below command
sudo pg_lsclusters
If you are using homebrew and homebrew services, you can probably just do:
brew services stop postgresql
brew upgrade postgresql
brew postgresql-upgrade-database
brew services start postgresql
I think this might not work completely if you are using advanced postgres features, but it worked perfectly for me.
Update: This process is the same for upgrading 9.5 through at least 11.5; simply modify the commands to reflect versions 9.6 and 10, where 9.6 is the old version and 10 is the new version. Be sure to adjust the "old" and "new" directories accordingly, too.
I just upgraded PostgreSQL 9.5 to 9.6 on Ubuntu and thought I'd share my findings, as there are a couple of OS/package-specific nuances of which to be aware.
(I didn't want to have to dump and restore data manually, so several of the other answers here were not viable.)
In short, the process consists of installing the new version of PostgreSQL alongside the old version (e.g., 9.5 and 9.6), and then running the pg_upgrade binary, which is explained in (some) detail at https://www.postgresql.org/docs/9.6/static/pgupgrade.html .
The only "tricky" aspect of pg_upgrade is that failure to pass the correct value for an argument, or failure to be logged-in as the correct user or cd to the correct location before executing a command, may lead to cryptic error messages.
On Ubuntu (and probably Debian), provided you are using the "official" repo, deb http://apt.postgresql.org/pub/repos/apt/ xenial-pgdg main, and provided you haven't changed the default filesystem paths or runtime options, the following procedure should do the job.
Install the new version (note that we specify the 9.6, explicitly):
sudo apt install postgresql-9.6
Once installation succeeds, both versions will be running side-by-side, but on different ports. The installation output mentions this, at the bottom, but it's easy to overlook:
Creating new cluster 9.6/main ...
config /etc/postgresql/9.6/main
data /var/lib/postgresql/9.6/main
locale en_US.UTF-8
socket /var/run/postgresql
port 5433
Stop both server instances (this will stop both at the same time):
sudo systemctl stop postgresql
Switch to the dedicated PostgreSQL system user:
su postgres
Move into his home directory (failure to do this will cause errors):
cd ~
pg_upgrade requires the following inputs (pg_upgrade --help tells us this):
When you run pg_upgrade, you must provide the following information:
the data directory for the old cluster (-d DATADIR)
the data directory for the new cluster (-D DATADIR)
the "bin" directory for the old version (-b BINDIR)
the "bin" directory for the new version (-B BINDIR)
These inputs may be specified with "long names", to make them easier to visualize:
-b, --old-bindir=BINDIR old cluster executable directory
-B, --new-bindir=BINDIR new cluster executable directory
-d, --old-datadir=DATADIR old cluster data directory
-D, --new-datadir=DATADIR new cluster data directory
We must also pass the --new-options switch, because failure to do so results in the following:
connection to database failed: could not connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket "/var/lib/postgresql/.s.PGSQL.50432"?
This occurs because the default configuration options are applied in the absence of this switch, which results in incorrect connection options being used, hence the socket error.
Execute the pg_upgrade command from the new PostgreSQL version:
/usr/lib/postgresql/9.6/bin/pg_upgrade --old-bindir=/usr/lib/postgresql/9.5/bin --new-bindir=/usr/lib/postgresql/9.6/bin --old-datadir=/var/lib/postgresql/9.5/main --new-datadir=/var/lib/postgresql/9.6/main --old-options=-cconfig_file=/etc/postgresql/9.5/main/postgresql.conf --new-options=-cconfig_file=/etc/postgresql/9.6/main/postgresql.conf
Logout of the dedicated system user account:
exit
The upgrade is now complete, but, the new instance will bind to port 5433 (the standard default is 5432), so keep this in mind if attempting to test the new instance before "cutting-over" to it.
Start the server as normal (again, this will start both the old and new instances):
systemctl start postgresql
If you want to make the new version the default, you will need to edit the effective configuration file, e.g., /etc/postgresql/9.6/main/postgresql.conf, and ensure that the port is defined as such:
port = 5432
If you do this, either change the old version's port number to 5433 at the same time (before starting the services), or, simply remove the old version (this will not remove your actual database content; you would need to use apt --purge remove postgresql-9.5 for that to happen):
apt remove postgresql-9.5
The above command will stop all instances, so you'll need to start the new instance one last time with:
systemctl start postgresql
As a final point of note, don't forget to consider pg_upgrade's good advice:
Upgrade Complete
----------------
Optimizer statistics are not transferred by pg_upgrade so,
once you start the new server, consider running:
./analyze_new_cluster.sh
Running this script will delete the old cluster's data files:
./delete_old_cluster.sh
The user manual covers this topic in depth. You can:
pg_upgrade in-place; or
pg_dump and pg_restore.
If in doubt, do it with dumps. Don't delete the old data directory, just keep it in case something goes wrong / you make a mistake; that way you can just go back to your unchanged 9.3 install.
For details, see the manual.
If you're stuck, post a detailed question explaining how you're stuck, where, and what you tried first. It depends a bit on how you installed PostgreSQL too, as there are several different "distributions" of PostgreSQL for OS X (unfortunately). So you'd need to provide that info.
Standing on the shoulders of the other poor creatures trodding through this muck, I was able to follow these steps to get back up and running after an upgrade to Yosemite:
Assuming you've used home-brew to install and upgrade Postgres, you can perform the following steps.
Stop current Postgres server:
launchctl unload ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist
Initialize a new 9.4 database:
initdb /usr/local/var/postgres9.4 -E utf8
Install postgres 9.3 (as it was no longer present on my machine):
brew install homebrew/versions/postgresql93
Add directories removed during Yosemite upgrade:
mkdir -p /usr/local/var/postgres/{pg_tblspc,pg_twophase,pg_stat_tmp}/touch /usr/local/var/postgres/{pg_tblspc,pg_twophase,pg_stat_tmp}/.keep
run pg_upgrade:
pg_upgrade -v -d /usr/local/var/postgres -D /usr/local/var/postgres9.4 -b /usr/local/Cellar/postgresql93/9.3.5/bin/ -B /usr/local/Cellar/postgresql/9.4.0/bin/
Move new data into place:
cd /usr/local/var
mv postgres postgres9.3
mv postgres9.4 postgres
Restart Postgres:
launchctl load ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist
Check /usr/local/var/postgres/server.log for details and to make sure the new server started properly.
Finally, re-install related libraries?
pip install --upgrade psycopg2
gem uninstall pg
gem install pg
Looks like the solution has been baked into Homebrew now:
$ brew info postgresql
...
==> Caveats
To migrate existing data from a previous major version of PostgreSQL run:
brew postgresql-upgrade-database
....
On Windows I kept facing different errors messages when trying to use pg_upgrade.
Saved a lot of time for me to just:
Backup DB
Uninstall all copies of PostgreSQL
Install 9.5
Restore DB
This did it for me.
https://gist.github.com/dideler/60c9ce184198666e5ab4
Short and to the point. I honestly don't aim to understand the guts of PostgreSQL, I want to get stuff done.
My solution for upgrading from Postgresql 11 to Postgresql 12 on Windows 10 is the following.
As a first remark you will need to be able stop and start the Postgresql service. You can do this by the following commands in Powershell.
Start:
pg_ctl start -D “d:\postgresql\11\data”
Stop:
pg_ctl stop -D “d:\postgresql\11\data”
Status:
pg_ctl status -D “d:\postgresql\11\data”
It would be wise to make a backup before doing the upgrade. The Postgresql 11 instance must be running. Then to copy the globals do
pg_dumpall -U postgres -g -f d:\bakup\postgresql\11\globals.sql
and then for each database
pg_dump -U postgres -Fc <database> > d:\backup\postgresql\11\<database>.fc
or
pg_dump -U postgres -Fc -d <database> -f d:\backup\postgresql\11\<database>.fc
If not already done install Postgresql 12 (as Postgresql 11 is also installed this will be on port 5433)
Then to do the upgrade as follows:
1) Stop Postgresql 11 service (see above)
2) Edit the postgresql.conf file in d:\postgresql\12\data and change port = 5433 to port = 5432
3) Edit the windows user environment path (windows start then type env) to point to Postgresql 12 instead of Postresql 11
4) Run upgrade by entering the following command.
pg_upgrade `
-b “c:\program files\postgresql\11\bin” `
-B “c:\program files\postgresql\12\bin” `
-d “d:\postgresql\11\data” `
-D “d:\postgresql\12\data” --username=postgres
(In powershell use backtick (or backquote) ` to continue the command on the next line)
5) and finally start the new Postgresql 12 service
pg_ctl start -D “d:\postgresql\12\data”
My solution was to do a combination of these two resources:
https://gist.github.com/tamoyal/2ea1fcdf99c819b4e07d
and
http://www.gab.lc/articles/migration_postgresql_9-3_to_9-4
The second one helped more then the first one. Also to not, don't follow the steps as is as some are not necessary.
Also, if you are not being able to backup the data via postgres console, you can use alternative approach, and backup it with pgAdmin 3 or some other program, like I did in my case.
Also, the link: https://help.ubuntu.com/stable/serverguide/postgresql.html
Helped to set the encrypted password and set md5 for authenticating the postgres user.
After all is done, to check the postgres server version run in terminal:
sudo -u postgres psql postgres
After entering the password run in postgres terminal:
SHOW SERVER_VERSION;
It will output something like:
server_version
----------------
9.4.5
For setting and starting postgres I have used command:
> sudo bash # root
> su postgres # postgres
> /etc/init.d/postgresql start
> /etc/init.d/postgresql stop
And then for restoring database from a file:
> psql -f /home/ubuntu_username/Backup_93.sql postgres
Or if doesn't work try with this one:
> pg_restore --verbose --clean --no-acl --no-owner -h localhost -U postgres -d name_of_database ~/your_file.dump
And if you are using Rails do a bundle exec rake db:migrate after pulling the code :)
For Mac via homebrew:
brew tap petere/postgresql,
brew install <formula> (eg: brew install petere/postgresql/postgresql-9.6)
Remove old Postgres:
brew unlink postgresql
brew link -f postgresql-9.6
If any error happen, don't forget to read and follow brew instruction in each step.
Check this out for more: https://github.com/petere/homebrew-postgresql
On Windows 10 since I had npm, I installed rimraf package. npm install rimraf -g
Backup all your databases one by one using command pg_dump -U $username --format=c --file=$mydatabase.sqlc $dbname
Then Installed Latest PostgreSQL Version i.e. 11.2 which prompted me to use port 5433 this time.
Followed by Uninstall of older versions of PostgreSQL mine was 10. Note the uninstaller may give a warning of not deleting folder C:\PostgreSQL\10\data. That's why we have the next step using rimraf to permanently delete the folder and it's sub-folders.
change into PostgreSQL install directory and ran the command rimraf 10. 10 is a directory name. Note use your older version of PostgreSQL i.e. 9.5 or something.
Now add C:\PostgreSQL\pg11\bin, C:\PostgreSQL\pg11\lib into the Windows environmental variables. Note my new installed version is 11 thus why I am using pg11.
Navigate to C:\PostgreSQL\data\pg11 then open postgresql.conf edit port = 5433 to port = 5432
That's it. Open cmd and type psql -U postgres
You can now restore all your backed databases one by one using the command pg_restore -U $username --dbname=$databasename $filename
I think this is best link for your solution to update postgres to 9.6
https://sandymadaan.wordpress.com/2017/02/21/upgrade-postgresql9-3-9-6-in-ubuntu-retaining-the-databases/