https://github.com/fidanf/ansible-role-pgpool
Installs and configures PgPool-II for Debian/Ubuntu.
https://github.com/fidanf/ansible-role-pgpool
high-availability load-balancing pgpool2 postgresql replication watchdog
Last synced: 3 months ago
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Installs and configures PgPool-II for Debian/Ubuntu.
- Host: GitHub
- URL: https://github.com/fidanf/ansible-role-pgpool
- Owner: fidanf
- License: mit
- Created: 2020-07-23T07:00:26.000Z (over 5 years ago)
- Default Branch: master
- Last Pushed: 2022-12-12T16:52:30.000Z (almost 3 years ago)
- Last Synced: 2025-04-30T11:55:38.420Z (6 months ago)
- Topics: high-availability, load-balancing, pgpool2, postgresql, replication, watchdog
- Language: Jinja
- Homepage:
- Size: 127 KB
- Stars: 8
- Watchers: 1
- Forks: 12
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
PgPool
=========
[](https://travis-ci.com/fidanf/ansible-role-pgpool)
Installs and configures PgPool-II for Debian/Ubuntu. The default _running mode_ is **streaming replication mode**.
Tested with :
- Debian 10.x :heavy_check_mark:
- Debian 11.x :heavy_check_mark:
- Ubuntu 18.04.x :heavy_check_mark:
- Ubuntu 20.04.x :heavy_check_mark:
> :warning: Only the major 4.1 is currently being handled and tested by this role.
Work is in progress to integrate the latest 4.3 which breaks a lot of current things.
For example, to install the version [4.1.4](https://www.pgpool.net/docs/42/en/html/release-4-1-4.html), Debian 11 hosts should set `pgpool_version_debian: 4.1.4-6.pgdg110+1`, whereas Ubuntu 20.04 hosts should rather use `pgpool_version_debian: 4.1.4-6.pgdg20.04+1`.
---
- [PgPool](#pgpool)
- [Requirements](#requirements)
- [Role Variables](#role-variables)
- [Dependencies](#dependencies)
- [Example Playbook](#example-playbook)
- [Configuration checking commands](#configuration-checking-commands)
- [PCP commands](#pcp-commands)
- [Handling server reboots](#handling-server-reboots)
- [License](#license)
Requirements
------------
- Python >=3.8
- Ansible-core >=2.12
See [./requirements.txt](./requirements.txt) for detailled dependencies used to develop the role.
Role Variables
--------------
Check out the [defaults.yml](./defaults/main.yml) file to retrieve the extended list of this role's variables.
Dependencies
------------
None
Example Playbook
----------------
Check out both [inventory.yml](./inventory.yml) and [example.yml](./example.yml) to get a picture of how this role should be used to integrate with an exisiting postgreSQL cluster managed by repmgr.
If you're looking for a role solely dedicated to provide such an environment, take a look at [ansible-role-postgresql-ha](https://github.com/fidanf/ansible-role-postgresql-ha)
Configuration checking commands
------------------------------
:warning: PgPool instance must be running
Show all configuration parameters
```bash
pgpool@pgpool01:~$ psql -h 192.168.56.30 -p 9999 -U admin -d testdb -c 'PGPOOL SHOW ALL'
```
Show pool status
```bash
pgpool@pgpool01:~$ psql -h 192.168.56.30 -p 9999 -U admin -d testdb -c 'SHOW POOL_NODES'
node_id | hostname | port | status | lb_weight | role | select_cnt | load_balance_node | replication_delay | replication_state | replication_sync_state | last_status_change
---------+----------+------+--------+-----------+---------+------------+-------------------+-------------------+-------------------+------------------------+---------------------
0 | pgsql01 | 5432 | up | 0.333333 | primary | 30 | true | 0 | | | 2020-07-27 14:50:55
1 | pgsql02 | 5432 | up | 0.333333 | standby | 13 | false | 0 | streaming | async | 2020-07-27 15:26:15
2 | pgsql03 | 5432 | up | 0.333333 | standby | 83 | false | 0 | streaming | async | 2020-07-27 14:50:55
(3 rows)
```
Feel free to create a .pgpass file for pgpool user in order to skip repetitive password prompts
More details at : https://www.pgpool.net/docs/latest/en/html/sql-commands.html
:warning: If for any reason PgPool's internal status is no longer in sync with Postgresql Replication' status, issue the following commands :
```bash
pgpool@pgpool01:~$ sudo systemctl stop pgpool2 && rm -f /var/log/pgpool/pgpool_status && sudo systemctl restart pgpool2
```
PCP commands
------------
Get pgpool status of backend node ID 0
```bash
pgpool@pgpool01:~$ pcp_node_info -h 127.0.0.1 -U pgpool -w -v 0
Password:
Hostname : pgsql01
Port : 5432
Status : 2
Weight : 0.333333
Status Name : up
Role : primary
Replication Delay : 0
Replication State :
Replication Sync State :
Last Status Change : 2020-07-27 14:50:55
```
Same thing against standby node
```bash
pgpool@pgpool01:~$ pcp_node_info -h 127.0.0.1 -U pgpool -w -v 1
Password:
Hostname : pgsql02
Port : 5432
Status : 2
Weight : 0.333333
Status Name : up
Role : standby
Replication Delay : 0
Replication State : streaming
Replication Sync State : async
Last Status Change : 2020-07-27 14:50:55
```
Attach pgpool node and give it and ID
```bash
pgpool@pgpool01:~$ pcp_attach_node -h 127.0.0.1 -U pgpool -w -n 3
```
Display the parameter values as defined in pgpool.conf
```bash
pgpool@pgpool01:~$ pcp_pool_status -h /var/run/pcp -U pgpool -w
```
Display PgPool's cluster status
```bash
pcp_watchdog_info -h 127.0.0.1 -U pgpool -w -v
```
Handling server reboots
-----------------------
Although using the recommended paths from the official documentation, socket directories seems to have unsufficient privileges to be able to recreate PIDs upon server reboots.
If you're running PgPool and PostgreSQL on the same servers, you may use the following configuration instead which solves the problem :
```yaml
pgpool_pid_file_name: /var/run/postgresql/pgpool.pid
pgpool_socket_dir: /var/run/postgresql
pgpool_pcp_socket_dir: /var/run/postgresql
pgpool_wd_ipc_socket_dir: /var/run/postgresql
```
More details at : https://www.pgpool.net/docs/latest/en/html/pcp-commands.html
License
-------
MIT / BSD