postgres-operator/docs/reference/cluster_manifest.md

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# Cluster manifest reference
Individual Postgres clusters are described by the Kubernetes *cluster manifest*
that has the structure defined by the `postgresql` CRD (custom resource
definition). The following section describes the structure of the manifest and
the purpose of individual keys. You can take a look at the examples of the
[minimal](../manifests/minimal-postgres-manifest.yaml)
and the
[complete](../manifests/complete-postgres-manifest.yaml)
cluster manifests.
When Kubernetes resources, such as memory, CPU or volumes, are configured,
their amount is usually described as a string together with the units of
measurements. Please, refer to the [Kubernetes
documentation](https://kubernetes.io/docs/concepts/configuration/manage-compute-resources-container/)
for the possible values of those.
:exclamation: If both operator configmap/CRD and a Postgres cluster manifest
define the same parameter, the value from the Postgres cluster manifest is
applied.
## Manifest structure
A Postgres manifest is a `YAML` document. On the top level both individual
parameters and parameter groups can be defined. Parameter names are written
in camelCase.
## Cluster metadata
Those parameters are grouped under the `metadata` top-level key.
* **name**
the name of the cluster. Must start with the `teamId` followed by a dash.
Changing it after the cluster creation is not supported. Required field.
* **namespace**
the namespace where the operator creates Kubernetes objects (i.e. pods,
services, secrets) for the cluster. Changing it after the cluster creation
results in deploying or updating a completely separate cluster in the target
namespace. Optional (if present, should match the namespace where the
manifest is applied).
* **labels**
if labels are matching one of the `inherited_labels` [configured in the
operator parameters](operator_parameters.md#kubernetes-resources),
they will automatically be added to all the objects (StatefulSet, Service,
Endpoints, etc.) that are created by the operator.
Labels that are set here but not listed as `inherited_labels` in the operator
parameters are ignored.
## Top-level parameters
These parameters are grouped directly under the `spec` key in the manifest.
* **teamId**
name of the team the cluster belongs to. Changing it after the cluster
creation is not supported. Required field.
* **numberOfInstances**
total number of instances for a given cluster. The operator parameters
`max_instances` and `min_instances` may also adjust this number. Required
field.
* **dockerImage**
custom docker image that overrides the **docker_image** operator parameter.
It should be a [Spilo](https://github.com/zalando/spilo) image. Optional.
* **spiloFSGroup**
the Persistent Volumes for the Spilo pods in the StatefulSet will be owned and
writable by the group ID specified. This will override the **spilo_fsgroup**
operator parameter. This is required to run Spilo as a non-root process, but
requires a custom Spilo image. Note the FSGroup of a Pod cannot be changed
without recreating a new Pod. Optional.
* **enableMasterLoadBalancer**
boolean flag to override the operator defaults (set by the
`enable_master_load_balancer` parameter) to define whether to enable the load
balancer pointing to the Postgres primary. Optional.
* **enableReplicaLoadBalancer**
boolean flag to override the operator defaults (set by the
`enable_replica_load_balancer` parameter) to define whether to enable the
load balancer pointing to the Postgres standby instances. Optional.
* **allowedSourceRanges**
when one or more load balancers are enabled for the cluster, this parameter
defines the comma-separated range of IP networks (in CIDR-notation). The
corresponding load balancer is accessible only to the networks defined by
this parameter. Optional, when empty the load balancer service becomes
inaccessible from outside of the Kubernetes cluster.
* **users**
a map of usernames to user flags for the users that should be created in the
cluster by the operator. User flags are a list, allowed elements are
`SUPERUSER`, `REPLICATION`, `INHERIT`, `LOGIN`, `NOLOGIN`, `CREATEROLE`,
`CREATEDB`, `BYPASSURL`. A login user is created by default unless NOLOGIN is
specified, in which case the operator creates a role. One can specify empty
flags by providing a JSON empty array '*[]*'. Optional.
* **databases**
a map of database names to database owners for the databases that should be
created by the operator. The owner users should already exist on the cluster
(i.e. mentioned in the `user` parameter). Optional.
* **tolerations**
a list of tolerations that apply to the cluster pods. Each element of that
list is a dictionary with the following fields: `key`, `operator`, `value`,
`effect` and `tolerationSeconds`. Each field is optional. See [Kubernetes
examples](https://kubernetes.io/docs/concepts/configuration/taint-and-toleration/)
for details on tolerations and possible values of those keys. When set, this
value overrides the `pod_toleration` setting from the operator. Optional.
* **podPriorityClassName**
a name of the [priority
class](https://kubernetes.io/docs/concepts/configuration/pod-priority-preemption/#priorityclass)
that should be assigned to the cluster pods. When not specified, the value
is taken from the `pod_priority_class_name` operator parameter, if not set
then the default priority class is taken. The priority class itself must be
defined in advance. Optional.
* **enableShmVolume**
Start a database pod without limitations on shm memory. By default docker
limit `/dev/shm` to `64M` (see e.g. the [docker
issue](https://github.com/docker-library/postgres/issues/416), which could be
not enough if PostgreSQL uses parallel workers heavily. If this option is
present and value is `true`, to the target database pod will be mounted a new
tmpfs volume to remove this limitation. If it's not present, the decision
about mounting a volume will be made based on operator configuration
(`enable_shm_volume`, which is `true` by default). It it's present and value
is `false`, then no volume will be mounted no matter how operator was
configured (so you can override the operator configuration). Optional.
* **enableLogicalBackup**
Determines if the logical backup of this cluster should be taken and uploaded
to S3. Default: false. Optional.
* **logicalBackupSchedule**
Schedule for the logical backup k8s cron job. Please take
[the reference schedule format](https://kubernetes.io/docs/tasks/job/automated-tasks-with-cron-jobs/#schedule)
into account. Optional. Default is: "30 00 \* \* \*"
## Postgres parameters
Those parameters are grouped under the `postgresql` top-level key, which is
required in the manifest.
* **version**
the Postgres major version of the cluster. Looks at the [Spilo
project](https://github.com/zalando/spilo/releases) for the list of supported
versions. Changing the cluster version once the cluster has been bootstrapped
is not supported. Required field.
* **parameters**
a dictionary of Postgres parameter names and values to apply to the resulting
cluster. Optional (Spilo automatically sets reasonable defaults for parameters
like `work_mem` or `max_connections`).
## Patroni parameters
Those parameters are grouped under the `patroni` top-level key. See the [Patroni
documentation](https://patroni.readthedocs.io/en/latest/SETTINGS.html) for the
explanation of `ttl` and `loop_wait` parameters.
* **initdb**
a map of key-value pairs describing initdb parameters. For `data-checksum`,
`debug`, `no-locale`, `noclean`, `nosync` and `sync-only` parameters use
`true` as the value if you want to set them. Changes to this option do not
affect the already initialized clusters. Optional.
* **pg_hba**
list of custom `pg_hba` lines to replace default ones. Note that the default
ones include
```
hostsll all +pamrole all pam
```
, where pamrole is the name of the role for the pam authentication; any
custom `pg_hba` should include the pam line to avoid breaking pam
authentication. Optional.
* **ttl**
Patroni `ttl` parameter value, optional. The default is set by the Spilo
docker image. Optional.
* **loop_wait**
Patroni `loop_wait` parameter value, optional. The default is set by the
Spilo docker image. Optional.
* **retry_timeout**
Patroni `retry_timeout` parameter value, optional. The default is set by the
Spilo docker image. Optional.
* **maximum_lag_on_failover**
Patroni `maximum_lag_on_failover` parameter value, optional. The default is
set by the Spilo docker image. Optional.
* **slots**
permanent replication slots that Patroni preserves after failover by
re-creating them on the new primary immediately after doing a promote. Slots
could be reconfigured with the help of `patronictl edit-config`. It is the
responsibility of a user to avoid clashes in names between replication slots
automatically created by Patroni for cluster members and permanent replication
slots. Optional.
## Postgres container resources
Those parameters define [CPU and memory requests and limits](https://kubernetes.io/docs/concepts/configuration/manage-compute-resources-container/)
for the Postgres container. They are grouped under the `resources` top-level
key with subgroups `requests` and `limits`.
### Requests
CPU and memory requests for the Postgres container.
* **cpu**
CPU requests for the Postgres container. Optional, overrides the
`default_cpu_requests` operator configuration parameter. Optional.
* **memory**
memory requests for the Postgres container. Optional, overrides the
`default_memory_request` operator configuration parameter. Optional.
### Limits
CPU and memory limits for the Postgres container.
* **cpu**
CPU limits for the Postgres container. Optional, overrides the
`default_cpu_limits` operator configuration parameter. Optional.
* **memory**
memory limits for the Postgres container. Optional, overrides the
`default_memory_limits` operator configuration parameter. Optional.
## Parameters defining how to clone the cluster from another one
Those parameters are applied when the cluster should be a clone of another one
that is either already running or has a basebackup on S3. They are grouped
under the `clone` top-level key and do not affect the already running cluster.
* **cluster**
name of the cluster to clone from. Translated to either the service name or
the key inside the S3 bucket containing base backups. Required when the
`clone` section is present.
* **uid**
Kubernetes UID of the cluster to clone from. Since cluster name is not a
unique identifier of the cluster (as identically named clusters may exist in
different namespaces) , the operator uses UID in the S3 bucket name in order
to guarantee uniqueness. Has no effect when cloning from the running
clusters. Optional.
* **timestamp**
the timestamp up to which the recovery should proceed. The operator always
configures non-inclusive recovery target, stopping right before the given
timestamp. When this parameter is set the operator will not consider cloning
from the live cluster, even if it is running, and instead goes to S3. Optional.
* **s3_wal_path**
the url to S3 bucket containing the WAL archive of the cluster to be cloned.
Optional.
* **s3_endpoint**
the url of the S3-compatible service should be set when cloning from non AWS
S3. Optional.
* **s3_access_key_id**
the access key id, used for authentication on S3 service. Optional.
* **s3_secret_access_key**
the secret access key, used for authentication on S3 service. Optional.
* **s3_force_path_style**
to enable path-style addressing(i.e., http://s3.amazonaws.com/BUCKET/KEY)
when connecting to an S3-compatible service that lack of support for
sub-domain style bucket URLs (i.e., http://BUCKET.s3.amazonaws.com/KEY).
Optional.
## Standby cluster
On startup, an existing `standby` top-level key creates a standby Postgres
cluster streaming from a remote location. So far only streaming from a S3 WAL
archive is supported.
* **s3_wal_path**
the url to S3 bucket containing the WAL archive of the remote primary.
Required when the `standby` section is present.
## EBS volume resizing
Those parameters are grouped under the `volume` top-level key and define the
properties of the persistent storage that stores Postgres data.
* **size**
the size of the target EBS volume. Usual Kubernetes size modifiers, i.e. `Gi`
or `Mi`, apply. Required.
* **storageClass**
the name of the Kubernetes storage class to draw the persistent volume from.
See [Kubernetes
documentation](https://kubernetes.io/docs/concepts/storage/storage-classes/)
for the details on storage classes. Optional.
* **subPath**
Subpath to use when mounting volume into Spilo container. Optional.
## Sidecar definitions
Those parameters are defined under the `sidecars` key. They consist of a list
of dictionaries, each defining one sidecar (an extra container running
along the main Postgres container on the same pod). The following keys can be
defined in the sidecar dictionary:
* **name**
name of the sidecar. Required.
* **image**
docker image of the sidecar. Required.
* **env**
a dictionary of environment variables. Use usual Kubernetes definition
(https://kubernetes.io/docs/tasks/inject-data-application/environment-variable-expose-pod-information/)
for environment variables. Optional.
* **resources**
[CPU and memory requests and limits](https://kubernetes.io/docs/concepts/configuration/manage-compute-resources-container)
for each sidecar container. Optional.
### Requests
CPU and memory requests for the sidecar container.
* **cpu**
CPU requests for the sidecar container. Optional, overrides the
`default_cpu_requests` operator configuration parameter. Optional.
* **memory**
memory requests for the sidecar container. Optional, overrides the
`default_memory_request` operator configuration parameter. Optional.
### Limits
CPU and memory limits for the sidecar container.
* **cpu**
CPU limits for the sidecar container. Optional, overrides the
`default_cpu_limits` operator configuration parameter. Optional.
* **memory**
memory limits for the sidecar container. Optional, overrides the
`default_memory_limits` operator configuration parameter. Optional.