8.8 KiB
stage | group | info | type |
---|---|---|---|
Enablement | Database | To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments | reference |
Working with the bundled PgBouncer service (PREMIUM SELF)
PgBouncer is used to seamlessly migrate database connections between servers in a failover scenario. Additionally, it can be used in a non-fault-tolerant setup to pool connections, speeding up response time while reducing resource usage.
GitLab Premium includes a bundled version of PgBouncer that can be managed
through /etc/gitlab/gitlab.rb
.
PgBouncer as part of a fault-tolerant GitLab installation
This content has been moved to a new location.
PgBouncer as part of a non-fault-tolerant GitLab installation
-
Generate PGBOUNCER_USER_PASSWORD_HASH with the command
gitlab-ctl pg-password-md5 pgbouncer
-
Generate SQL_USER_PASSWORD_HASH with the command
gitlab-ctl pg-password-md5 gitlab
. Enter the plaintext SQL_USER_PASSWORD later. -
On your database node, ensure the following is set in your
/etc/gitlab/gitlab.rb
postgresql['pgbouncer_user_password'] = 'PGBOUNCER_USER_PASSWORD_HASH' postgresql['sql_user_password'] = 'SQL_USER_PASSWORD_HASH' postgresql['listen_address'] = 'XX.XX.XX.Y' # Where XX.XX.XX.Y is the ip address on the node postgresql should listen on postgresql['md5_auth_cidr_addresses'] = %w(AA.AA.AA.B/32) # Where AA.AA.AA.B is the IP address of the pgbouncer node
-
Run
gitlab-ctl reconfigure
NOTE: If the database was already running, it needs to be restarted after reconfigure by running
gitlab-ctl restart postgresql
. -
On the node you are running PgBouncer on, make sure the following is set in
/etc/gitlab/gitlab.rb
pgbouncer['enable'] = true pgbouncer['databases'] = { gitlabhq_production: { host: 'DATABASE_HOST', user: 'pgbouncer', password: 'PGBOUNCER_USER_PASSWORD_HASH' } }
-
Run
gitlab-ctl reconfigure
-
On the node running Puma, make sure the following is set in
/etc/gitlab/gitlab.rb
gitlab_rails['db_host'] = 'PGBOUNCER_HOST' gitlab_rails['db_port'] = '6432' gitlab_rails['db_password'] = 'SQL_USER_PASSWORD'
-
Run
gitlab-ctl reconfigure
-
At this point, your instance should connect to the database through PgBouncer. If you are having issues, see the Troubleshooting section
Backups
Do not backup or restore GitLab through a PgBouncer connection: it causes a GitLab outage.
Read more about this and how to reconfigure backups.
Enable Monitoring
Introduced in GitLab 12.0.
If you enable Monitoring, it must be enabled on all PgBouncer servers.
-
Create/edit
/etc/gitlab/gitlab.rb
and add the following configuration:# Enable service discovery for Prometheus consul['enable'] = true consul['monitoring_service_discovery'] = true # Replace placeholders # Y.Y.Y.Y consul1.gitlab.example.com Z.Z.Z.Z # with the addresses of the Consul server nodes consul['configuration'] = { retry_join: %w(Y.Y.Y.Y consul1.gitlab.example.com Z.Z.Z.Z), } # Set the network addresses that the exporters will listen on node_exporter['listen_address'] = '0.0.0.0:9100' pgbouncer_exporter['listen_address'] = '0.0.0.0:9188'
-
Run
sudo gitlab-ctl reconfigure
to compile the configuration.
Administrative console
As part of Omnibus GitLab, a command is provided to automatically connect to the PgBouncer administrative console. See the PgBouncer documentation for detailed instructions on how to interact with the console.
To start a session run the following and provide the password for the pgbouncer
user:
sudo gitlab-ctl pgb-console
To get some basic information about the instance:
pgbouncer=# show databases; show clients; show servers;
name | host | port | database | force_user | pool_size | reserve_pool | pool_mode | max_connections | current_connections
---------------------+-----------+------+---------------------+------------+-----------+--------------+-----------+-----------------+---------------------
gitlabhq_production | 127.0.0.1 | 5432 | gitlabhq_production | | 100 | 5 | | 0 | 1
pgbouncer | | 6432 | pgbouncer | pgbouncer | 2 | 0 | statement | 0 | 0
(2 rows)
type | user | database | state | addr | port | local_addr | local_port | connect_time | request_time | ptr | link
| remote_pid | tls
------+-----------+---------------------+--------+-----------+-------+------------+------------+---------------------+---------------------+-----------+------
+------------+-----
C | gitlab | gitlabhq_production | active | 127.0.0.1 | 44590 | 127.0.0.1 | 6432 | 2018-04-24 22:13:10 | 2018-04-24 22:17:10 | 0x12444c0 |
| 0 |
C | gitlab | gitlabhq_production | active | 127.0.0.1 | 44592 | 127.0.0.1 | 6432 | 2018-04-24 22:13:10 | 2018-04-24 22:17:10 | 0x12447c0 |
| 0 |
C | gitlab | gitlabhq_production | active | 127.0.0.1 | 44594 | 127.0.0.1 | 6432 | 2018-04-24 22:13:10 | 2018-04-24 22:17:10 | 0x1244940 |
| 0 |
C | gitlab | gitlabhq_production | active | 127.0.0.1 | 44706 | 127.0.0.1 | 6432 | 2018-04-24 22:14:22 | 2018-04-24 22:16:31 | 0x1244ac0 |
| 0 |
C | gitlab | gitlabhq_production | active | 127.0.0.1 | 44708 | 127.0.0.1 | 6432 | 2018-04-24 22:14:22 | 2018-04-24 22:15:15 | 0x1244c40 |
| 0 |
C | gitlab | gitlabhq_production | active | 127.0.0.1 | 44794 | 127.0.0.1 | 6432 | 2018-04-24 22:15:15 | 2018-04-24 22:15:15 | 0x1244dc0 |
| 0 |
C | gitlab | gitlabhq_production | active | 127.0.0.1 | 44798 | 127.0.0.1 | 6432 | 2018-04-24 22:15:15 | 2018-04-24 22:16:31 | 0x1244f40 |
| 0 |
C | pgbouncer | pgbouncer | active | 127.0.0.1 | 44660 | 127.0.0.1 | 6432 | 2018-04-24 22:13:51 | 2018-04-24 22:17:12 | 0x1244640 |
| 0 |
(8 rows)
type | user | database | state | addr | port | local_addr | local_port | connect_time | request_time | ptr | link | rem
ote_pid | tls
------+--------+---------------------+-------+-----------+------+------------+------------+---------------------+---------------------+-----------+------+----
--------+-----
S | gitlab | gitlabhq_production | idle | 127.0.0.1 | 5432 | 127.0.0.1 | 35646 | 2018-04-24 22:15:15 | 2018-04-24 22:17:10 | 0x124dca0 | |
19980 |
(1 row)
Procedure for bypassing PgBouncer
Some database changes have to be done directly, and not through PgBouncer.
Read more about the affected tasks: database restores and GitLab upgrades.
-
To find the primary node, run the following on a database node:
sudo gitlab-ctl repmgr cluster show
-
Edit
/etc/gitlab/gitlab.rb
on the application node you're performing the task on, and updategitlab_rails['db_host']
andgitlab_rails['db_port']
with the database primary's host and port. -
Run reconfigure:
sudo gitlab-ctl reconfigure
Once you've performed the tasks or procedure, switch back to using PgBouncer:
-
Change back
/etc/gitlab/gitlab.rb
to point to PgBouncer. -
Run reconfigure:
sudo gitlab-ctl reconfigure
Troubleshooting
In case you are experiencing any issues connecting through PgBouncer, the first place to check is always the logs:
sudo gitlab-ctl tail pgbouncer
Additionally, you can check the output from show databases
in the
administrative console. In the output, you would expect
to see values in the host
field for the gitlabhq_production
database.
Additionally, current_connections
should be greater than 1.
Message: LOG: invalid CIDR mask in address
See the suggested fix in Geo documentation.
Message: LOG: invalid IP mask "md5": Name or service not known
See the suggested fix in Geo documentation.