OpenShift PostgreSQL: Difference between revisions

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* [[OpenShift Auxiliary Tools Operations#Operations|OpenShift Auxiliary Tools Operations]]
* [[OpenShift Auxiliary Tools Operations#Operations|OpenShift Auxiliary Tools Operations]]
* [[Postgresql]]
* [[PostgreSQL]]


=Installation=
=Installation=
==PostgreSQL Image Notes==
The Posgresql container image contains a README.md in usr/share/container-scripts/postgresql and a setup script in usr/share/container-scripts/postgresql/common.sh.
The [[Docker_Concepts#Entrypoint|entrypoint script]] will first run [[PostgreSQL_DDL_Operations#initdb|initdb]] which will create the user (POSTGRESQL_USER) and the database (POSTGRESQL_DATABASE).


==Create OpenShift Infrastructure==
==Create OpenShift Infrastructure==


You can use the following generic Postgresql template: https://github.com/NovaOrdis/playground/blob/master/openshift/auxiliary-tools/generic-postgresql.yaml
You can use the following generic PostgreSQL template: https://github.com/NovaOrdis/playground/blob/master/openshift/auxiliary-tools/generic-postgresql.yaml


Copy it locally. Normally, you should not need to modify it manually, unless you want to use newer versions.
Copy it locally. Normally, you should not need to modify it manually, unless you want to use newer versions.
Line 15: Line 21:


  [[oc process]] -f ./generic-postgresql.yaml \
  [[oc process]] -f ./generic-postgresql.yaml \
   --param APPLICATION_NAME=... \
   -p APPLICATION_NAME=... \
   --param POSTGRESQL_USER=... \
   -p POSTGRESQL_USER=... \
   --param POSTGRESQL_PASSWORD=... \
   -p POSTGRESQL_PASSWORD=... \
   --param POSTGRESQL_DATABASE=... \
   -p POSTGRESQL_DATABASE=... \
  | [[oc create]] -f -
  | [[oc create]] -f -


==Create the User and the Database==
==Create the Database==
 
Log into the pod:
 
oc rsh <''postgres-pod-name''>
createdb <''dbname''>
 
The user is already created.
 
<font color=red>'''TODO''': Investigate why the a custom user ('gogs') is created automatically, but the database is not.</font>


==Activate the Readiness Probe==
==Activate the Readiness Probe==
Modify the specification of the "postgresql" container with
oc edit dc/<''dc-name''>
Add the following readiness probe, under the liveness probe:
          readinessProbe:
            exec:
              command:
              - /bin/sh
              - -i
              - -c
              - psql -h 127.0.0.1 -U $POSTGRESQL_USER -q -d $POSTGRESQL_DATABASE -c 'SELECT 1'
            failureThreshold: 3
            initialDelaySeconds: 5
            periodSeconds: 10
            successThreshold: 1
            timeoutSeconds: 1

Latest revision as of 06:53, 19 October 2018

Internal

Installation

PostgreSQL Image Notes

The Posgresql container image contains a README.md in usr/share/container-scripts/postgresql and a setup script in usr/share/container-scripts/postgresql/common.sh.

The entrypoint script will first run initdb which will create the user (POSTGRESQL_USER) and the database (POSTGRESQL_DATABASE).

Create OpenShift Infrastructure

You can use the following generic PostgreSQL template: https://github.com/NovaOrdis/playground/blob/master/openshift/auxiliary-tools/generic-postgresql.yaml

Copy it locally. Normally, you should not need to modify it manually, unless you want to use newer versions.

Make sure that a persistent volume 1Gi or larger is available for binding.

oc process -f ./generic-postgresql.yaml \
 -p APPLICATION_NAME=... \
 -p POSTGRESQL_USER=... \
 -p POSTGRESQL_PASSWORD=... \
 -p POSTGRESQL_DATABASE=... \
| oc create -f -

Create the Database

Log into the pod:

oc rsh <postgres-pod-name>
createdb <dbname>

The user is already created.

TODO: Investigate why the a custom user ('gogs') is created automatically, but the database is not.

Activate the Readiness Probe

Modify the specification of the "postgresql" container with

oc edit dc/<dc-name>

Add the following readiness probe, under the liveness probe:

         readinessProbe:
           exec:
             command:
             - /bin/sh
             - -i
             - -c
             - psql -h 127.0.0.1 -U $POSTGRESQL_USER -q -d $POSTGRESQL_DATABASE -c 'SELECT 1'
           failureThreshold: 3
           initialDelaySeconds: 5
           periodSeconds: 10
           successThreshold: 1
           timeoutSeconds: 1