The configuration is loaded from either the path specified by the -c flag or /etc/pgagroal/pgagroal.conf.
The configuration of pgagroal is split into sections using the [ and ] characters.
The main section, called [pgagroal], is where you configure the overall properties
of the connection pool.
The other sections configure each one server. There can be no more than 64 server sections, therefore
no more than 64 servers configured as backends.
Server sections don't have any requirements to their naming so you can give them
meaningful names like [primary] for the primary PostgreSQL
instance.
In any case, it is not possible to have duplicated sections, that means section names must be unique within the configuration file.
All properties within a section are in the format key = value.
The characters # and ; can be used for comments. A line is totally ignored if the
very first non-space character is a comment one, but it is possible to put a comment at the end of a line.
The Bool data type supports the following values: on, yes, 1, true, off, no, 0 and false.
Each value can be quoted by means of " or '. Quoted strings must begin and end with the very same quoting character. It is possible to nest quotes.
As an example of configuration snippet including quoting and comments:
# This line is ignored since it starts with '#'
# and so is this one
log_line_prefix = "PGAGROAL #%Y-%m-%d-%H:%M:%S" # quoted because it contains spaces
log_type= console#log to stdout
pipeline = 'performance' # no need to quote since it does not contain any spaces
See a more complete sample configuration for running pgagroal on localhost.
This section is mandatory and the pooler will refuse to start if the configuration file does not specify one and only one. Usually this section is place on top of the configuration file, but its position within the file does not really matter. The available keys and their accepted values are reported in the table below.
| Property | Default | Unit | Required | Description |
|---|---|---|---|---|
| host | String | Yes | The bind address for pgagroal | |
| port | Int | Yes | The bind port for pgagroal | |
| unix_socket_dir | String | Yes | The Unix Domain Socket location | |
| metrics | 0 | Int | No | The metrics port (disable = 0) |
| metrics_cache_max_age | 0 | String | No | The number of seconds to keep in cache a Prometheus (metrics) response. If set to zero, the caching will be disabled. Can be a string with a suffix, like 2m to indicate 2 minutes |
| metrics_cache_max_size | 256k | String | No | The maximum amount of data to keep in cache when serving Prometheus responses. Changes require restart. This parameter determines the size of memory allocated for the cache even if metrics_cache_max_age or metrics are disabled. Its value, however, is taken into account only if metrics_cache_max_age is set to a non-zero value. Supports suffixes: 'B' (bytes), the default if omitted, 'K' or 'KB' (kilobytes), 'M' or 'MB' (megabytes), 'G' or 'GB' (gigabytes). |
| management | 0 | Int | No | The remote management port (disable = 0) |
| log_type | console | String | No | The logging type (console, file, syslog) |
| log_level | info | String | No | The logging level, any of the (case insensitive) strings FATAL, ERROR, WARN, INFO and DEBUG (that can be more specific as DEBUG1 thru DEBUG5). Debug level greater than 5 will be set to DEBUG5. Not recognized values will make the log_level be INFO |
| log_path | pgagroal.log | String | No | The log file location. Can be a strftime(3) compatible string. |
| log_rotation_age | 0 | String | No | The age that will trigger a log file rotation. If expressed as a positive number, is managed as seconds. Supports suffixes: 'S' (seconds, the default), 'M' (minutes), 'H' (hours), 'D' (days), 'W' (weeks). A value of 0 disables. |
| log_rotation_size | 0 | String | No | The size of the log file that will trigger a log rotation. Supports suffixes: 'B' (bytes), the default if omitted, 'K' or 'KB' (kilobytes), 'M' or 'MB' (megabytes), 'G' or 'GB' (gigabytes). A value of 0 (with or without suffix) disables. |
| log_line_prefix | %Y-%m-%d %H:%M:%S | String | No | A strftime(3) compatible string to use as prefix for every log line. Must be quoted if contains spaces. |
| log_mode | append | String | No | Append to or create the log file (append, create) |
| log_connections | off |
Bool | No | Log connects |
| log_disconnections | off |
Bool | No | Log disconnects |
| blocking_timeout | 30 | Int | No | The number of seconds the process will be blocking for a connection (disable = 0) |
| idle_timeout | 0 | Int | No | The number of seconds a connection is been kept alive (disable = 0) |
| rotate_frontend_password_timeout | 0 | Int | No | The number of seconds after which the passwords of frontend users are updated periodically (disable = 0) |
| rotate_frontend_password_length | 8 | Int | No | The length of the randomized frontend password |
| max_connection_age | 0 | Int | No | The maximum number of seconds that a connection will live (disable = 0) |
| validation | off |
String | No | Should connection validation be performed. Valid options: off, foreground and background |
| background_interval | 300 | Int | No | The interval between background validation scans in seconds |
| max_retries | 5 | Int | No | The maximum number of iterations to obtain a connection |
| max_connections | 100 | Int | No | The maximum number of connections to PostgreSQL (max 10000) |
| allow_unknown_users | true |
Bool | No | Allow unknown users to connect |
| authentication_timeout | 5 | Int | No | The number of seconds the process will wait for valid credentials |
| pipeline | auto |
String | No | The pipeline type (auto, performance, session, transaction) |
| auth_query | off |
Bool | No | Enable authentication query |
| failover | off |
Bool | No | Enable failover support |
| failover_script | String | No | The failover script to execute | |
| tls | off |
Bool | No | Enable Transport Layer Security (TLS) |
| tls_cert_file | String | No | Certificate file for TLS. This file must be owned by either the user running pgagroal or root. | |
| tls_key_file | String | No | Private key file for TLS. This file must be owned by either the user running pgagroal or root. Additionally permissions must be at least 0640 when owned by root or 0600 otherwise. |
|
| tls_ca_file | String | No | Certificate Authority (CA) file for TLS. This file must be owned by either the user running pgagroal or root. | |
| libev | auto |
String | No | Select the libev backend to use. Valid options: auto, select, poll, epoll, iouring, devpoll and port |
| buffer_size | 65535 | Int | No | The network buffer size (SO_RCVBUF and SO_SNDBUF) |
| keep_alive | on | Bool | No | Have SO_KEEPALIVE on sockets |
| nodelay | on | Bool | No | Have TCP_NODELAY on sockets |
| non_blocking | off | Bool | No | Have O_NONBLOCK on sockets |
| backlog | max_connections / 4 |
Int | No | The backlog for listen(). Minimum 16 |
| hugepage | try |
String | No | Huge page support (off, try, on) |
| tracker | off | Bool | No | Track connection lifecycle |
| track_prepared_statements | off | Bool | No | Track prepared statements (transaction pooling) |
| pidfile | String | No | Path to the PID file. If omitted, automatically set to unix_socket_dir/pgagroal.port.pid |
|
| update_process_title | verbose |
String | No | The behavior for updating the operating system process title, mainly related to connection processes. Allowed settings are: never (or off), does not update the process title; strict to set the process title without overriding the existing initial process title length; minimal to set the process title to username/database; verbose (or full) to set the process title to user@host:port/database. Please note that strict and minimal are honored only on those systems that do not provide a native way to set the process title (e.g., Linux). On other systems, there is no difference between strict and minimal and the assumed behaviour is minimal even if strict is used. never and verbose are always honored, on every system. On Linux systems the process title is always trimmed to 255 characters, while on system that provide a natve way to set the process title it can be longer. |
Danger zone
| Property | Default | Unit | Required | Description |
|---|---|---|---|---|
| disconnect_client | 0 | Int | No | Disconnect clients that have been idle for more than the specified seconds. This setting DOES NOT take long running transactions into account |
| disconnect_client_force | off | Bool | No | Disconnect clients that have been active for more than the specified seconds. This setting DOES NOT take long running transactions into account |
Each section with a name different from pgagroal will be treated as an host section.
There can be up to 64 host sections, each with an unique name and different combination of host and port settings, otherwise the pooler will complain about duplicated server configuration.
| Property | Default | Unit | Required | Description |
|---|---|---|---|---|
| host | String | Yes | The address of the PostgreSQL instance | |
| port | Int | Yes | The port of the PostgreSQL instance | |
| primary | Bool | No | Identify the instance as primary (hint) | |
| tls | off |
Bool | No | Enable Transport Layer Security (TLS) support (Experimental - no pooling). Changes require restart. |
| tls_cert_file | String | No | Certificate file for TLS. This file must be owned by either the user running pgagroal or root. Changes require restart. | |
| tls_key_file | String | No | Private key file for TLS. This file must be owned by either the user running pgagroal or root. Additionally permissions must be at least 0640 when owned by root or 0600 otherwise.Changes require restart. |
|
| tls_ca_file | String | No | Certificate Authority (CA) file for TLS. This file must be owned by either the user running pgagroal or root. Changes require restart. |
Note, that if host starts with a / it represents a path and pgagroal will connect using a Unix Domain Socket.
The pgagroal_hba configuration controls access to pgagroal through host-based authentication.
The configuration is loaded from either the path specified by the -a flag or /etc/pgagroal/pgagroal_hba.conf.
The format of the file follows the similar PostgreSQL HBA configuration format, and as such looks like
#
# TYPE DATABASE USER ADDRESS METHOD
#
host all all all all
| Column | Required | Description |
|---|---|---|
| TYPE | Yes | Specifies the access method for clients. host and hostssl are supported |
| DATABASE | Yes | Specifies the database for the rule. Either specific name or all for all databases |
| USER | Yes | Specifies the user for the rule. Either specific name or all for all users |
| ADDRESS | Yes | Specifies the network for the rule. all for all networks, or IPv4 address with a mask (0.0.0.0/0) or IPv6 address with a mask (::0/0) |
| METHOD | Yes | Specifies the authentication mode for the user. all for all methods, otherwise trust, reject, password, md5 or scram-sha-256 |
Remote management users needs to have their database set to admin in order for the entry to be considered.
There could be up to 64 HBA entries in the configuration file.
The pgagroal_databases configuration defines limits for a database or a user or both. The limits are the number
of connections from pgagroal to PostgreSQL for each entry.
The file also defines the initial and minimum pool size for a database and user pair. Note, that this feature requires a user definition file, see below.
The configuration is loaded from either the path specified by the -l flag or /etc/pgagroal/pgagroal_databases.conf.
#
# DATABASE USER MAX_SIZE INITIAL_SIZE MIN_SIZE
#
mydb myuser all
anotherdb userB 10 5 3
| Column | Required | Description |
|---|---|---|
| DATABASE | Yes | Specifies the database for the rule. all for all databases |
| USER | Yes | Specifies the user for the rule. all for all users |
| MAX_SIZE | Yes | Specifies the maximum pool size for the entry. all for all remaining counts from max_connections |
| INITIAL_SIZE | No | Specifies the initial pool size for the entry. all for MAX_SIZE connections. Default is 0 |
| MIN_SIZE | No | Specifies the minimum pool size for the entry. all for MAX_SIZE connections. Default is 0 |
There can be up to 64 entries in the configuration file.
In the case a limit entry has incoherent values, for example INITIAL_SIZE smaller than MIN_SIZE, the system will try to automatically adjust the settings on the fly, reporting messages in the logs.
The system will find the best match limit entry for a given DATABASE-USER pair according to the following rules:
- Use the first entry with an exact
DATABASEandUSERmatch. - If there is no exact match, use the entry with a
USERmatch andDATABASEset toall. - If Rule 2 does not apply, use the entry with a
DATABASEmatch andUSERset toall.
The pgagroal_users configuration defines the users known to the system. This file is created and managed through
the pgagroal-admin tool.
The configuration is loaded from either the path specified by the -u flag or /etc/pgagroal/pgagroal_users.conf.
There can be up to 64 users known to pgagroal.
The pgagroal_frontend_users configuration defines the passwords for the users connecting to pgagroal.
This allows the setup to use different passwords for the pgagroal to PostgreSQL authentication.
This file is created and managed through the pgagroal-admin tool.
All users defined in the frontend authentication must be defined in the user vault (-u).
Frontend users (-F) requires a user vault (-u) to be defined.
The configuration is loaded from either the path specified by the -F flag or /etc/pgagroal/pgagroal_frontend_users.conf.
The pgagroal_admins configuration defines the administrators known to the system. This file is created and managed through
the pgagroal-admin tool.
The configuration is loaded from either the path specified by the -A flag or /etc/pgagroal/pgagroal_admins.conf.
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.
The pgagroal_superuser configuration defines the superuser known to the system. This file is created and managed through
the pgagroal-admin tool. It may only have one user defined.
The configuration is loaded from either the path specified by the -S flag or /etc/pgagroal/pgagroal_superuser.conf.