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Getting started with pgagroal

First of all, make sure that pgagroal is installed and in your path by using pgagroal -?. You should see

pgagroal 1.6.0
  High-performance connection pool for PostgreSQL

  pgagroal [ -c CONFIG_FILE ] [ -a HBA_FILE ] [ -d ]

  -c, --config CONFIG_FILE           Set the path to the pgagroal.conf file
  -a, --hba HBA_FILE                 Set the path to the pgagroal_hba.conf file
  -l, --limit LIMIT_FILE             Set the path to the pgagroal_databases.conf file
  -u, --users USERS_FILE             Set the path to the pgagroal_users.conf file
  -F, --frontend FRONTEND_USERS_FILE Set the path to the pgagroal_frontend_users.conf file
  -A, --admins ADMINS_FILE           Set the path to the pgagroal_admins.conf file
  -S, --superuser SUPERUSER_FILE     Set the path to the pgagroal_superuser.conf file
  -d, --daemon                       Run as a daemon
  -V, --version                      Display version information
  -?, --help                         Display help

If you don't have pgagroal in your path see README on how to compile and install pgagroal in your system.


Lets create a simple configuration file called pgagroal.conf with the content

host = *
port = 2345

log_type = file
log_level = info
log_path = /tmp/pgagroal.log

max_connections = 100
idle_timeout = 600
validation = off
unix_socket_dir = /tmp/

host = localhost
port = 5432

In our main section called [pgagroal] we setup pgagroal to listen on all network addresses on port 2345. Logging will be performed at info level and put in a file called /tmp/pgagroal.log. We want a maximum of 100 connections that are being closed if they have been idle for 10 minutes, and we also specify that we don't want any connection validation to be performed. Last we specify the location of the unix_socket_dir used for management operations.

Next we create a section called [primary] which has the information about our PostgreSQL instance. In this case it is running on localhost on port 5432.

Now we need a host based authentication (HBA) file. Create one called pgagroal_hba.conf with the content

host    all      all   all      all

This tells pgagroal that it can accept connections from all network addresses for all databases and all user names.

We are now ready to run pgagroal.

See Configuration for all configuration options.


We will run pgagroal using the command

pgagroal -c pgagroal.conf -a pgagroal_hba.conf

If this doesn't give an error, then we are ready to connect.

We will assume that we have a user called test with the password test in our PostgreSQL instance. See their documentation on how to setup PostgreSQL, add a user and add a database.

We will connect to pgagroal using the psql application.

psql -h localhost -p 2345 -U test test

That should give you a password prompt where test should be typed in. You are now connected to PostgreSQL through pgagroal.

Type \q to quit psql and pgagroal will now put the connection that you used into its pool.

If you type the above psql command again pgagroal will reuse the existing connection and thereby lower the overhead of getting a connection to PostgreSQL.

Now you are ready to point your applications to use pgagroal instead of going directly to PostgreSQL. pgagroal will work with any PostgreSQL compliant driver, for example pgjdbc, Npgsql and pq.

pgagroal is stopped by pressing Ctrl-C (^C) in the console where you started it, or by sending the SIGTERM signal to the process using kill <pid>.

Run-time administration

pgagroal has a run-time administration tool called pgagroal-cli.

You can see the commands it supports by using pgagroal-cli -? which will give

pgagroal-cli 1.6.0
  Command line utility for pgagroal

  pgagroal-cli [ -c CONFIG_FILE ] [ COMMAND ]

  -c, --config CONFIG_FILE Set the path to the pgagroal.conf file
  -h, --host HOST          Set the host name
  -p, --port PORT          Set the port number
  -U, --user USERNAME      Set the user name
  -P, --password PASSWORD  Set the password
  -L, --logfile FILE       Set the log file
  -v, --verbose            Output text string of result
  -V, --version            Display version information
  -?, --help               Display help

  flush-idle               Flush idle connections
  flush-gracefully         Flush all connections gracefully
  flush-all                Flush all connections. USE WITH CAUTION !
  is-alive                 Is pgagroal alive
  enable                   Enable a database
  disable                  Disable a database
  gracefully               Stop pgagroal gracefully
  stop                     Stop pgagroal
  cancel-shutdown          Cancel the graceful shutdown
  status                   Status of pgagroal
  details                  Detailed status of pgagroal
  switch-to                Switch to another primary
  reload                   Reload the configuration
  reset                    Reset the Prometheus statistics
  reset-server             Reset the state of a server

This tool can be used on the machine running pgagroal to flush connections.

To flush all idle connections you would use

pgagroal-cli -c pgagroal.conf flush-idle

To stop pgagroal you would use

pgagroal-cli -c pgagroal.conf stop

Check the outcome of the operations by verifying the exit code, like

echo $?

or by using the -v flag.

If pgagroal has both Transport Layer Security (TLS) and management enabled then pgagroal-cli can connect with TLS using the files ~/.pgagroal/pgagroal.key (must be 0600 permission), ~/.pgagroal/pgagroal.crt and ~/.pgagroal/root.crt.


pgagroal has an administration tool called pgagroal-admin, which is used to control user registration with pgagroal.

You can see the commands it supports by using pgagroal-admin -? which will give

pgagroal-admin 1.6.0
  Administration utility for pgagroal

  pgagroal-admin [ -f FILE ] [ COMMAND ]

  -f, --file FILE         Set the path to a user file
  -U, --user USER         Set the user name
  -P, --password PASSWORD Set the password for the user
  -g, --generate          Generate a password
  -l, --length            Password length
  -V, --version           Display version information
  -?, --help              Display help

  master-key              Create or update the master key
  add-user                Add a user
  update-user             Update a user
  remove-user             Remove a user
  list-users              List all users

In order to set the master key for all users you can use

pgagroal-admin -g master-key

The master key must be at least 8 characters.

Then use the other commands to add, update, remove or list the current user names, f.ex.

pgagroal-admin -f pgagroal_users.conf add-user

Next Steps

Next steps in improving pgagroal's configuration could be

  • Update pgagroal.conf with the required settings for your system
  • Set the access rights in pgagroal_hba.conf for each user and database
  • Add a pgagroal_users.conf file using pgagroal-admin with a list of known users
  • Disable access for unknown users by setting allow_unknown_users to false
  • Define a pgagroal_databases.conf file with the limits and prefill settings for each database
  • Enable Transport Layer Security v1.2+ (TLS)
  • Deploy Grafana dashboard

See Configuration for more information on these subjects.


There are a few short tutorials available to help you better understand and configure pgagroal:


The pgagroal community hopes that you find the project interesting.

Feel free to

All contributions are most welcome !

Please, consult our Code of Conduct policies for interacting in our community.

Consider giving the project a star on GitHub if you find it useful. And, feel free to follow the project on Twitter as well.