Kubectl Plugin ============== .. raw:: html CloudNativePG provides a plugin for ``kubectl`` to manage a cluster in Kubernetes. Install ------- You can install the ``cnpg`` plugin using a variety of methods. .. Note:: For air-gapped systems, installation via package managers, using previously downloaded files, may be a good option. 　 Via the installation script ^^^^^^^^^^^^^^^^^^^^^^^^^^^ .. code:: sh curl -sSfL \ https://github.com/cloudnative-pg/cloudnative-pg/raw/main/hack/install-cnpg-plugin.sh | \ sudo sh -s -- -b /usr/local/bin Using the Debian or RedHat packages ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ In the `releases section of the GitHub repository `_ , you can navigate to any release of interest (pick the same or newer release than your CloudNativePG operator), and in it you will find an **Assets** section. In that section are pre-built packages for a variety of systems. As a result, you can follow standard practices and instructions to install them in your systems. Debian packages ^^^^^^^^^^^^^^^ For example, let’s install the 1.28.0 release of the plugin, for an Intel based 64 bit server. First, we download the right ``.deb`` file. .. code:: sh wget https://github.com/cloudnative-pg/cloudnative-pg/releases/download/v1.28.0/kubectl-cnpg_1.28.0_linux_x86_64.deb \ --output-document kube-plugin.deb Then, with superuser privileges, install from the local file using ``dpkg`` : .. code:: console $ sudo dpkg -i kube-plugin.deb Selecting previously unselected package cnpg. (Reading database ... 6688 files and directories currently installed.) Preparing to unpack kube-plugin.deb ... Unpacking cnpg (1.28.0) ... Setting up cnpg (1.28.0) ... RPM packages ^^^^^^^^^^^^ As in the example for ``.rpm`` packages, let’s install the 1.28.0 release for an Intel 64 bit machine. Note the ``--output`` flag to provide a file name. .. code:: sh curl -L https://github.com/cloudnative-pg/cloudnative-pg/releases/download/v1.28.0/kubectl-cnpg_1.28.0_linux_x86_64.rpm \ --output kube-plugin.rpm Then, with superuser privileges, install with ``yum`` , and you’re ready to use: .. code:: console $ sudo yum --disablerepo=* localinstall kube-plugin.rpm Failed to set locale, defaulting to C.UTF-8 Dependencies resolved. ==================================================================================================== Package Architecture Version Repository Size ==================================================================================================== Installing: cnpg x86_64 1.28.0 @commandline 20 M Transaction Summary ==================================================================================================== Install 1 Package Total size: 20 M Installed size: 78 M Is this ok [y/N]: y Using the Arch Linux User Repository (AUR) Package ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ To install the plugin from the `AUR `_ , follow these steps: .. code:: sh git clone https://aur.archlinux.org/kubectl-cnpg.git cd kubectl-cnpg makepkg -si Or use your favorite AUR-helper, for example `paru `_ : .. code:: sh paru -S kubectl-cnpg Using Krew ^^^^^^^^^^ If you already have `Krew `_ installed, you can simply run: .. code:: sh kubectl krew install cnpg When a new version of the plugin is released, you can update the existing installation with: .. code:: sh kubectl krew update kubectl krew upgrade cnpg Using Homebrew ^^^^^^^^^^^^^^ .. Note:: Please note that the Homebrew community manages the availability of the `kubectl-cnpg plugin on Homebrew `_ . 　 If you already have `Homebrew `_ installed, you can simply run: .. code:: sh brew install kubectl-cnpg When a new version of the plugin is released, you can update the existing installation with: .. code:: sh brew update brew upgrade kubectl-cnpg .. Note:: Auto-completion for the kubectl plugin is already managed by Homebrew. There's no need to create the `kubectl_complete-cnpg` script mentioned below. 　 Supported Architectures ^^^^^^^^^^^^^^^^^^^^^^^ CloudNativePG Plugin is currently built for the following operating system and architectures: - Linux - amd64 - arm 5/6/7 - arm64 - s390x - ppc64le - macOS - amd64 - arm64 - Windows - 386 - amd64 - arm 5/6/7 - arm64 Configuring auto-completion ^^^^^^^^^^^^^^^^^^^^^^^^^^^ To configure auto-completion for the plugin, a helper shell script needs to be installed into your current PATH. Assuming the latter contains ``/usr/local/bin`` , this can be done with the following commands: .. code:: sh cat > kubectl_complete-cnpg < operator.yaml The flags in the above command have the following meaning: - ``-n king`` install the CNPG operator into the ``king`` namespace - ``--version 1.23`` install the latest patch version for minor version 1.23 - ``--replicas 3`` install the operator with 3 replicas - ``--watch-namespace "albert, bb, freddie"`` have the operator watch for changes in the ``albert`` , ``bb`` and ``freddie`` namespaces only Status ^^^^^^ The ``status`` command provides an overview of the current status of your cluster, including: - **general information**: name of the cluster, PostgreSQL’s system ID, number of instances, current timeline and position in the WAL - **backup**: point of recoverability, and WAL archiving status as returned by the ``pg_stat_archiver`` view from the primary - or designated primary in the case of a replica cluster - **streaming replication**: information taken directly from the ``pg_stat_replication`` view on the primary instance - **instances**: information about each Postgres instance, taken directly by each instance manager; in the case of a standby, the ``Current LSN`` field corresponds to the latest write-ahead log location that has been replayed during recovery (replay LSN). .. Note:: The status information above is taken at different times and at different locations, resulting in slightly inconsistent returned values. For example, the `Current Write LSN` location in the main header, might be different from the `Current LSN` field in the instances status as it is taken at two different time intervals. 　 .. code:: sh kubectl cnpg status sandbox .. code:: output Cluster Summary Name: default/sandbox System ID: 7423474350493388827 PostgreSQL Image: ghcr.io/cloudnative-pg/postgresql:16.4 Primary instance: sandbox-1 Primary start time: 2024-10-08 18:31:57 +0000 UTC (uptime 1m14s) Status: Cluster in healthy state Instances: 3 Ready instances: 3 Size: 126M Current Write LSN: 0/604DE38 (Timeline: 1 - WAL File: 000000010000000000000006) Continuous Backup status Not configured Streaming Replication status Replication Slots Enabled Name Sent LSN Write LSN Flush LSN Replay LSN Write Lag Flush Lag Replay Lag State Sync State Sync Priority Replication Slot - --- -------- --------- --------- ---------- --------- --------- ---------- ----- ---------- ------------- ---------------- sandbox-2 0/604DE38 0/604DE38 0/604DE38 0/604DE38 00:00:00 00:00:00 00:00:00 streaming async 0 active sandbox-3 0/604DE38 0/604DE38 0/604DE38 0/604DE38 00:00:00 00:00:00 00:00:00 streaming async 0 active Instances status Name Current LSN Replication role Status QoS Manager Version Node - --- ----------- ---------------- ------ --- --------------- ---- sandbox-1 0/604DE38 Primary OK BestEffort 1.28.0 k8s-eu-worker sandbox-2 0/604DE38 Standby (async) OK BestEffort 1.28.0 k8s-eu-worker2 sandbox-3 0/604DE38 Standby (async) OK BestEffort 1.28.0 k8s-eu-worker If you require more detailed status information, use the ``--verbose`` option (or ``-v`` for short). The level of detail increases each time the flag is repeated: .. code:: sh kubectl cnpg status sandbox --verbose .. code:: output Cluster Summary Name: default/sandbox System ID: 7423474350493388827 PostgreSQL Image: ghcr.io/cloudnative-pg/postgresql:16.4 Primary instance: sandbox-1 Primary start time: 2024-10-08 18:31:57 +0000 UTC (uptime 2m4s) Status: Cluster in healthy state Instances: 3 Ready instances: 3 Size: 126M Current Write LSN: 0/6053720 (Timeline: 1 - WAL File: 000000010000000000000006) Continuous Backup status Not configured Physical backups No running physical backups found Streaming Replication status Replication Slots Enabled Name Sent LSN Write LSN Flush LSN Replay LSN Write Lag Flush Lag Replay Lag State Sync State Sync Priority Replication Slot Slot Restart LSN Slot WAL Status Slot Safe WAL Size - --- -------- --------- --------- ---------- --------- --------- ---------- ----- ---------- ------------- ---------------- ---------------- --------------- ------------------ sandbox-2 0/6053720 0/6053720 0/6053720 0/6053720 00:00:00 00:00:00 00:00:00 streaming async 0 active 0/6053720 reserved NULL sandbox-3 0/6053720 0/6053720 0/6053720 0/6053720 00:00:00 00:00:00 00:00:00 streaming async 0 active 0/6053720 reserved NULL Unmanaged Replication Slot Status No unmanaged replication slots found Managed roles status No roles managed Tablespaces status No managed tablespaces Pod Disruption Budgets status Name Role Expected Pods Current Healthy Minimum Desired Healthy Disruptions Allowed - --- ---- ------------- --------------- ----------------------- ------------------- sandbox replica 2 2 1 1 sandbox-primary primary 1 1 1 0 Instances status Name Current LSN Replication role Status QoS Manager Version Node - --- ----------- ---------------- ------ --- --------------- ---- sandbox-1 0/6053720 Primary OK BestEffort 1.28.0 k8s-eu-worker sandbox-2 0/6053720 Standby (async) OK BestEffort 1.28.0 k8s-eu-worker2 sandbox-3 0/6053720 Standby (async) OK BestEffort 1.28.0 k8s-eu-worker With an additional ``-v`` (e.g. ``kubectl cnpg status sandbox -v -v`` ), you can also view PostgreSQL configuration, HBA settings, and certificates. The command also supports output in ``yaml`` and ``json`` format. .. Note:: The `status` command executes operations that access the pod filesystem, such as `du` to calculate cluster size and `cat` to read configuration files. For clusters with large data volumes (e.g., over 1TB), these operations may take longer than the default timeout of 10 seconds. You can adjust the timeout using the `--timeout` flag (e.g., `kubectl cnpg status sandbox --timeout 45s` ). 　 Promote ^^^^^^^ The meaning of this command is to ``promote`` a pod in the cluster to primary, so you can start with maintenance work or test a switch-over situation in your cluster: .. code:: sh kubectl cnpg promote CLUSTER CLUSTER-INSTANCE Or you can use the instance node number to promote: .. code:: sh kubectl cnpg promote CLUSTER INSTANCE Certificates ^^^^^^^^^^^^ Clusters created using the CloudNativePG operator work with a CA to sign a TLS authentication certificate. To get a certificate, you need to provide a name for the secret to store the credentials, the cluster name, and a user for this certificate: .. code:: sh kubectl cnpg certificate cluster-cert --cnpg-cluster CLUSTER --cnpg-user USER After the secret it’s created, you can get it using ``kubectl`` : .. code:: sh kubectl get secret cluster-cert And the content of the same in plain text using the following commands: .. code:: sh kubectl get secret cluster-cert -o json | jq -r .data | map(@base64d) | .[] Restart ^^^^^^^ The ``kubectl cnpg restart`` command can be used in two cases: - requesting the operator to orchestrate a rollout restart for a certain cluster. This is useful to apply configuration changes to cluster dependent objects, such as ``ConfigMaps`` containing custom monitoring queries. - request a single instance restart, either in-place if the instance is the cluster’s primary or deleting and recreating the pod if it is a replica. .. code:: sh ## this command will restart a whole cluster in a rollout fashion kubectl cnpg restart CLUSTER ## this command will restart a single instance, according to the policy above kubectl cnpg restart CLUSTER INSTANCE If the in-place restart is requested but the change cannot be applied without a switchover, the switchover will take precedence over the in-place restart. A common case for this will be a minor upgrade of PostgreSQL image. .. Note:: If you want ConfigMaps and Secrets to be **automatically** reloaded by instances, you can add a label with key `cnpg.io/reload` to it. 　 Reload ^^^^^^ The ``kubectl cnpg reload`` command requests the operator to trigger a reconciliation loop for a certain cluster. This is useful to apply configuration changes to cluster dependent objects, such as ConfigMaps containing custom monitoring queries. The following command will reload all configurations for a given cluster: .. code:: sh kubectl cnpg reload CLUSTER Maintenance ^^^^^^^^^^^ The ``kubectl cnpg maintenance`` command helps to modify one or more clusters across namespaces and set the maintenance window values, it will change the following fields: - ``.spec.nodeMaintenanceWindow.inProgress`` - ``.spec.nodeMaintenanceWindow.reusePVC`` Accepts as argument ``set`` and ``unset`` using this to set the ``inProgress`` to ``true`` in case ``set`` and to ``false`` in case of ``unset`` . By default, ``reusePVC`` is always set to ``false`` unless the ``--reusePVC`` flag is passed. The plugin will ask for a confirmation with a list of the cluster to modify and their new values, if this is accepted this action will be applied to all the cluster in the list. If you want to set in maintenance all the PostgreSQL in your Kubernetes cluster, just need to write the following command: .. code:: sh kubectl cnpg maintenance set --all-namespaces And you’ll have the list of all the cluster to update .. code:: output The following are the new values for the clusters Namespace Cluster Name Maintenance reusePVC - -------- ------------ ----------- -------- default cluster-example true false default pg-backup true false test cluster-example true false Do you want to proceed? [y/n]: y Report ^^^^^^ The ``kubectl cnpg report`` command bundles various pieces of information into a ZIP file. It aims to provide the needed context to debug problems with clusters in production. It has two sub-commands: ``operator`` and ``cluster`` . report Operator ^^^^^^^^^^^^^^^ The ``operator`` sub-command requests the operator to provide information regarding the operator deployment, configuration and events. .. Note:: All confidential information in Secrets and ConfigMaps is REDACTED. The Data map will show the **keys** but the values will be empty. The flag `-S` / `--stopRedaction` will defeat the redaction and show the values. Use only at your own risk, this will share private data. 　 .. Note:: By default, operator logs are not collected, but you can enable operator log collection with the `--logs` flag 　 .. Note:: The `report operator` command works with minimal permissions. Only the operator deployment is **required** - all other resources are optional and collected on a best-effort basis. If you lack permissions for certain resources (e.g., webhooks, OLM resources), warnings are logged and report generation continues with available data. 　 The report includes: - **deployment information** (required): the operator ``Deployment`` - **operator pods** (optional): the operator ``Pod`` information - **configuration** (optional): ``Secrets`` and ``ConfigMaps`` in the operator namespace - **events** (optional): ``Events`` in the operator namespace - **webhook configuration** (optional): mutating and validating webhook configurations (cluster-scoped) - **webhook service** (optional): the webhook service - **OLM resources** (optional): subscriptions, cluster service versions, install plans (if OLM is installed) - **logs** (optional): operator ``Pod`` logs in JSON-lines format (requires ``--logs`` flag) .. Warning:: Read access (`get` ) to the operator deployment in the operator namespace. This allows namespace-scoped users to generate basic troubleshooting reports. 　 .. Note:: Add `list` on pods, events; `get` on secrets, configmaps, services (namespace-scoped); and `list` on webhook configurations (cluster-scoped). 　 A user with only namespace-scoped permissions can still generate useful reports: .. code:: sh ## With only deployment read access kubectl cnpg report operator -n cnpg-system -f report.zip .. Note:: The command will log warnings for inaccessible resources but successfully generate a report with the deployment manifest, which is often sufficient for basic troubleshooting. 　 The command will generate a ZIP file containing various manifest in YAML format (by default, but settable to JSON with the ``-o`` flag). Use the ``-f`` flag to name a result file explicitly. If the ``-f`` flag is not used, a default time-stamped filename is created for the zip file. .. Note:: The report plugin obeys `kubectl` conventions, and will look for objects constrained by namespace. The CNPG Operator will generally not be installed in the same namespace as the clusters. E.g. the default installation namespace is cnpg-system. 　 .. code:: sh kubectl cnpg report operator -n cnpg-system results in .. code:: output Successfully written report to "report_operator_.zip" (format: "yaml") With the ``-f`` flag set: .. code:: sh kubectl cnpg report operator -n cnpg-system -f reportRedacted.zip Unzipping the file will produce a time-stamped top-level folder to keep the directory tidy: .. code:: sh unzip reportRedacted.zip will result in: .. code:: output Archive: reportRedacted.zip creating: report_operator_/ creating: report_operator_/manifests/ inflating: report_operator_/manifests/deployment.yaml inflating: report_operator_/manifests/operator-pod.yaml inflating: report_operator_/manifests/events.yaml inflating: report_operator_/manifests/validating-webhook-configuration.yaml inflating: report_operator_/manifests/mutating-webhook-configuration.yaml inflating: report_operator_/manifests/webhook-service.yaml inflating: report_operator_/manifests/cnpg-ca-secret(secret).yaml inflating: report_operator_/manifests/cnpg-webhook-cert(secret).yaml If you activated the ``--logs`` option, you’d see an extra subdirectory: .. code:: output Archive: report_operator_.zip creating: report_operator_/operator-logs/ inflating: report_operator_/operator-logs/cnpg-controller-manager-66fb98dbc5-pxkmh-logs.jsonl .. Note:: The plugin will try to get the PREVIOUS operator's logs, which is helpful when investigating restarted operators. In all cases, it will also try to get the CURRENT operator logs. If current and previous logs are available, it will show them both. 　 .. code:: output ====== Beginning of Previous Log ===== 2023-03-28T12:56:41.251711811Z {"level":"info","ts":"2023-03-28T12:56:41Z","logger":"setup","msg":"Starting CloudNativePG Operator","version":"1.28.0","build":{"Version":"1.28.0+dev107","Commit":"cc9bab17","Date":"2023-03-28"}} 2023-03-28T12:56:41.251851909Z {"level":"info","ts":"2023-03-28T12:56:41Z","logger":"setup","msg":"Starting pprof HTTP server","addr":"0.0.0.0:6060"} ====== End of Previous Log ===== 2023-03-28T12:57:09.854306024Z {"level":"info","ts":"2023-03-28T12:57:09Z","logger":"setup","msg":"Starting CloudNativePG Operator","version":"1.28.0","build":{"Version":"1.28.0+dev107","Commit":"cc9bab17","Date":"2023-03-28"}} 2023-03-28T12:57:09.854363943Z {"level":"info","ts":"2023-03-28T12:57:09Z","logger":"setup","msg":"Starting pprof HTTP server","addr":"0.0.0.0:6060"} If the operator hasn’t been restarted, you’ll still see the ``====== Begin …`` and ``====== End …`` guards, with no content inside. You can verify that the confidential information is REDACTED by default: .. code:: sh cd report_operator_/manifests/ head cnpg-ca-secret\(secret\).yaml .. code:: yaml data: ca.crt: "" ca.key: "" metadata: creationTimestamp: "2022-03-22T10:42:28Z" managedFields: - apiVersion: v1 fieldsType: FieldsV1 fieldsV1: With the ``-S`` (``--stopRedaction`` ) option activated, secrets are shown: .. code:: sh kubectl cnpg report operator -n cnpg-system -f reportNonRedacted.zip -S You’ll get a reminder that you’re about to view confidential information: .. code:: output WARNING: secret Redaction is OFF. Use it with caution Successfully written report to "reportNonRedacted.zip" (format: "yaml") .. code:: sh unzip reportNonRedacted.zip head cnpg-ca-secret\(secret\).yaml .. code:: yaml data: ca.crt: LS0tLS1CRUdJTiBD… ca.key: LS0tLS1CRUdJTiBF… metadata: creationTimestamp: "2022-03-22T10:42:28Z" managedFields: - apiVersion: v1 fieldsType: FieldsV1 report Cluster ^^^^^^^^^^^^^^ The ``cluster`` sub-command gathers the following: - **cluster resources**: the cluster information, same as ``kubectl get cluster -o yaml`` - **cluster pods**: pods in the cluster namespace matching the cluster name - **cluster jobs**: jobs, if any, in the cluster namespace matching the cluster name - **events**: events in the cluster namespace - **pod logs**: logs for the cluster Pods (optional, off by default) in JSON-lines format - **job logs**: logs for the Pods created by jobs (optional, off by default) in JSON-lines format The ``cluster`` sub-command accepts the ``-f`` and ``-o`` flags, as the ``operator`` does. If the ``-f`` flag is not used, a default timestamped report name will be used. Note that the cluster information does not contain configuration Secrets / ConfigMaps, so the ``-S`` is disabled. .. Note:: By default, cluster logs are not collected, but you can enable cluster log collection with the `--logs` flag 　 Usage: .. code:: sh kubectl cnpg report cluster CLUSTER [flags] Note that, unlike the ``operator`` sub-command, for the ``cluster`` sub-command you need to provide the cluster name, and very likely the namespace, unless the cluster is in the default one. .. code:: sh kubectl cnpg report cluster CLUSTER -f report.zip [-n NAMESPACE] and then: .. code:: sh unzip report.zip .. code:: output Archive: report.zip creating: report_cluster_example_/ creating: report_cluster_example_/manifests/ inflating: report_cluster_example_/manifests/cluster.yaml inflating: report_cluster_example_/manifests/cluster-pods.yaml inflating: report_cluster_example_/manifests/cluster-jobs.yaml inflating: report_cluster_example_/manifests/events.yaml Remember that you can use the ``--logs`` flag to add the pod and job logs to the ZIP. .. code:: sh kubectl cnpg report cluster CLUSTER [-n NAMESPACE] --logs will result in: .. code:: output Successfully written report to "report_cluster_example_.zip" (format: "yaml") .. code:: sh unzip report_cluster_.zip .. code:: output Archive: report_cluster_example_.zip creating: report_cluster_example_/ creating: report_cluster_example_/manifests/ inflating: report_cluster_example_/manifests/cluster.yaml inflating: report_cluster_example_/manifests/cluster-pods.yaml inflating: report_cluster_example_/manifests/cluster-jobs.yaml inflating: report_cluster_example_/manifests/events.yaml creating: report_cluster_example_/logs/ inflating: report_cluster_example_/logs/cluster-example-full-1.jsonl creating: report_cluster_example_/job-logs/ inflating: report_cluster_example_/job-logs/cluster-example-full-1-initdb-qnnvw.jsonl inflating: report_cluster_example_/job-logs/cluster-example-full-2-join-tvj8r.jsonl Logs ^^^^ The ``kubectl cnpg logs`` command allows to follow the logs of a collection of pods related to CloudNativePG in a single go. It has at the moment one available sub-command: ``cluster`` . Cluster logs ^^^^^^^^^^^^ The ``cluster`` sub-command gathers all the pod logs for a cluster in a single stream or file. This means that you can get all the pod logs in a single terminal window, with a single invocation of the command. As in all the cnpg plugin sub-commands, you can get instructions and help with the ``-h`` flag: ``kubectl cnpg logs cluster -h`` The ``logs`` command will display logs in JSON-lines format, unless the ``--timestamps`` flag is used, in which case, a human-readable timestamp will be prepended to each line. In this case, lines will no longer be valid JSON, and tools such as ``jq`` may not work as desired. If the ``logs cluster`` sub-command is given the ``-f`` flag (aka ``--follow`` ), it will follow the cluster pod logs, and will also watch for any new pods created in the cluster after the command has been invoked. Any new pods found, including pods that have been restarted or re-created, will also have their pods followed. The logs will be displayed in the terminal’s standard-out. This command will only exit when the cluster has no more pods left, or when it is interrupted by the user. If ``logs`` is called without the ``-f`` option, it will read the logs from all cluster pods until the time of invocation and display them in the terminal’s standard-out, then exit. The ``-o`` or ``--output`` flag can be provided, to specify the name of the file where the logs should be saved, instead of displaying over standard-out. The ``--tail`` flag can be used to specify how many log lines will be retrieved from each pod in the cluster. By default, the ``logs cluster`` sub-command will display all the logs from each pod in the cluster. If combined with the “follow” flag ``-f`` , the number of logs specified by ``--tail`` will be retrieved until the current time, and from then the new logs will be followed. NOTE: unlike other ``cnpg`` plugin commands, the ``-f`` is used to denote “follow” rather than specify a file. This keeps with the convention of ``kubectl logs`` , which takes ``-f`` to mean the logs should be followed. Usage: .. code:: sh kubectl cnpg logs cluster CLUSTER [flags] Using the ``-f`` option to follow: .. code:: sh kubectl cnpg report cluster CLUSTER -f Using ``--tail`` option to display 3 lines from each pod and the ``-f`` option to follow: .. code:: sh kubectl cnpg report cluster CLUSTER -f --tail 3 .. code:: output {"level":"info","ts":"2023-06-30T13:37:33Z","logger":"postgres","msg":"2023-06-30 13:37:33.142 UTC [26] LOG: ending log output to stderr","source":"/controller/log/postgres","logging_pod":"cluster-example-3"} {"level":"info","ts":"2023-06-30T13:37:33Z","logger":"postgres","msg":"2023-06-30 13:37:33.142 UTC [26] HINT: Future log output will go to log destination \"csvlog\".","source":"/controller/log/postgres","logging_pod":"cluster-example-3"} … … With the ``-o`` option omitted, and with ``--output`` specified: .. code:: console $ kubectl cnpg logs cluster CLUSTER --output my-cluster.log Successfully written logs to "my-cluster.log" Pretty ^^^^^^ The ``pretty`` sub-command reads a log stream from standard input, formats it into a human-readable output, and attempts to sort the entries by timestamp. It can be used in combination with ``kubectl cnpg logs cluster`` , as shown in the following example: .. code:: console $ kubectl cnpg logs cluster cluster-example | kubectl cnpg logs pretty 2024-10-15T17:35:00.336 INFO cluster-example-1 instance-manager Starting CloudNativePG Instance Manager 2024-10-15T17:35:00.336 INFO cluster-example-1 instance-manager Checking for free disk space for WALs before starting PostgreSQL 2024-10-15T17:35:00.347 INFO cluster-example-1 instance-manager starting tablespace manager 2024-10-15T17:35:00.347 INFO cluster-example-1 instance-manager starting external server manager [...] Alternatively, it can be used in combination with other commands that produce CNPG logs in JSON format, such as ``stern`` , or ``kubectl logs`` , as in the following example: .. code:: console $ kubectl logs cluster-example-1 | kubectl cnpg logs pretty 2024-10-15T17:35:00.336 INFO cluster-example-1 instance-manager Starting CloudNativePG Instance Manager 2024-10-15T17:35:00.336 INFO cluster-example-1 instance-manager Checking for free disk space for WALs before starting PostgreSQL 2024-10-15T17:35:00.347 INFO cluster-example-1 instance-manager starting tablespace manager 2024-10-15T17:35:00.347 INFO cluster-example-1 instance-manager starting external server manager [...] The ``pretty`` sub-command also supports advanced log filtering, allowing users to display logs for specific pods or loggers, or to filter logs by severity level. Here’s an example: .. code:: console $ kubectl cnpg logs cluster cluster-example | kubectl cnpg logs pretty --pods cluster-example-1 --loggers postgres --log-level info 2024-10-15T17:35:00.509 INFO cluster-example-1 postgres 2024-10-15 17:35:00.509 UTC [29] LOG: redirecting log output to logging collector process 2024-10-15T17:35:00.509 INFO cluster-example-1 postgres 2024-10-15 17:35:00.509 UTC [29] HINT: Future log output will appear in directory "/controller/log"... 2024-10-15T17:35:00.510 INFO cluster-example-1 postgres 2024-10-15 17:35:00.509 UTC [29] LOG: ending log output to stderr 2024-10-15T17:35:00.510 INFO cluster-example-1 postgres ending log output to stderr [...] The ``pretty`` sub-command will try to sort the log stream, to make logs easier to reason about. In order to achieve this, it gathers the logs into groups, and within groups it sorts by timestamp. This is the only way to sort interactively, as ``pretty`` may be piped from a command in “follow” mode. The sub-command will add a group separator line, ``---`` , at the end of each sorted group. The size of the grouping can be configured via the ``--sorting-group-size`` flag (default: 1000), as illustrated in the following example: .. code:: console $ kubectl cnpg logs cluster cluster-example | kubectl cnpg logs pretty --sorting-group-size=3 2024-10-15T17:35:20.426 INFO cluster-example-2 instance-manager Starting CloudNativePG Instance Manager 2024-10-15T17:35:20.426 INFO cluster-example-2 instance-manager Checking for free disk space for WALs before starting PostgreSQL 2024-10-15T17:35:20.438 INFO cluster-example-2 instance-manager starting tablespace manager - -- 2024-10-15T17:35:20.438 INFO cluster-example-2 instance-manager starting external server manager 2024-10-15T17:35:20.438 INFO cluster-example-2 instance-manager starting controller-runtime manager 2024-10-15T17:35:20.439 INFO cluster-example-2 instance-manager Starting EventSource - -- [...] To explore all available options, use the ``-h`` flag for detailed explanations of the supported flags and their usage. .. Note:: You can also increase the verbosity of the log by adding more `-v` options. 　 Destroy ^^^^^^^ The ``kubectl cnpg destroy`` command helps remove an instance and all the associated PVCs from a Kubernetes cluster. The optional ``--keep-pvc`` flag, if specified, allows you to keep the PVCs, while removing all ``metadata.ownerReferences`` that were set by the instance. Additionally, the ``cnpg.io/pvcStatus`` label on the PVCs will change from ``ready`` to ``detached`` to signify that they are no longer in use. Running again the command without the ``--keep-pvc`` flag will remove the detached PVCs. Usage: .. code:: sh kubectl cnpg destroy CLUSTER INSTANCE The following example removes the ``cluster-example-2`` pod and the associated PVCs: .. code:: sh kubectl cnpg destroy cluster-example 2 Cluster Hibernation ^^^^^^^^^^^^^^^^^^^ There are times when you may need to temporarily suspend a CloudNativePG ``Cluster`` while preserving its data, allowing you to resume operations later. This feature is known as **cluster hibernation**. Hibernation is managed declaratively using the ``cnpg.io/hibernation`` annotation. .. Note:: For more details, see the :ref:`Declarative hibernation ` documentation page. 　 To simplify the process, the ``cnpg`` plugin for ``kubectl`` provides a ``hibernate`` command, which acts as a convenient shortcut for applying the annotation. To hibernate a cluster, run: .. code:: sh kubectl cnpg hibernate on CLUSTER This command applies the ``cnpg.io/hibernation=on`` annotation to the cluster, suspending its execution. To resume a hibernated cluster, use: .. code:: sh kubectl cnpg hibernate off CLUSTER This will remove the hibernation state by setting ``cnpg.io/hibernation=off`` . You can check the cluster’s status at any time with: .. code:: sh kubectl cnpg status CLUSTER This will display the current state of the cluster, including whether it is hibernated. Benchmarking the database with pgbench ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Pgbench can be run against an existing PostgreSQL cluster with following command: .. code:: sh kubectl cnpg pgbench CLUSTER -- --time 30 --client 1 --jobs 1 Refer to the :ref:`Benchmarking pgbench section ` for more details. Benchmarking the storage with fio ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ``fio`` can be run on an existing storage class with following command: .. code:: sh kubectl cnpg fio FIO_JOB_NAME [-n NAMESPACE] Refer to the :ref:`Benchmarking fio section ` for more details. Requesting a new physical backup ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ The ``kubectl cnpg backup`` command requests a new physical backup for an existing Postgres cluster by creating a new ``Backup`` resource. The following example requests an on-demand backup for a given cluster: .. code:: sh kubectl cnpg backup CLUSTER or, if using volume snapshots: .. code:: sh kubectl cnpg backup CLUSTER -m volumeSnapshot The created backup will be named after the request time: .. code:: console $ kubectl cnpg backup cluster-example backup/cluster-example-20230121002300 created By default, a newly created backup will use the backup target policy defined in the cluster to choose which instance to run on. However, you can override this policy with the ``--backup-target`` option. In the case of volume snapshot backups, you can also use the ``--online`` option to request an online/hot backup or an offline/cold one: additionally, you can also tune online backups by explicitly setting the ``--immediate-checkpoint`` and ``--wait-for-archive`` options. The :ref:`Appendix B - Backup on object stores ` contains more information about the configuration settings. Launching psql ^^^^^^^^^^^^^^ The ``kubectl cnpg psql CLUSTER`` command starts a new PostgreSQL interactive front-end process (psql) connected to an existing Postgres cluster, as if you were running it from the actual pod. This means that you will be using the ``postgres`` user. .. Note:: As you will be connecting as `postgres` user, in production environments this method should be used with extreme care, by authorized personnel only. 　 .. code:: console $ kubectl cnpg psql cluster-example psql (18.1 (Debian 18.1-1.pgdg110+1)) Type "help" for help. postgres=# By default, the command will connect to the primary instance. The user can select to work against a replica by using the ``--replica`` option: .. code:: console $ kubectl cnpg psql --replica cluster-example psql (18.1 (Debian 18.1-1.pgdg110+1)) Type "help" for help. postgres=# select pg_is_in_recovery(); pg_is_in_recovery - ------------------ t (1 row) postgres=# \q This command will start ``kubectl exec`` , and the ``kubectl`` executable must be reachable in your ``PATH`` variable to correctly work. Snapshotting a Postgres cluster ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ .. Warning:: The `kubectl cnpg snapshot` command has been removed. Please use the :ref:`Requesting a new physical backup ` to request backups using volume snapshots. 　 Using pgAdmin4 for evaluation/demonstration purposes only ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `pgAdmin `_ stands as the most popular and feature-rich open-source administration and development platform for PostgreSQL. For more information on the project, please refer to the official `documentation `_ . Given that the pgAdmin Development Team maintains official Docker container images, you can install pgAdmin in your environment as a standard Kubernetes deployment. .. Note:: Deployment of pgAdmin in Kubernetes production environments is beyond the scope of this document and, more broadly, of the CloudNativePG project. 　 However, **for the purposes of demonstration and evaluation**, CloudNativePG offers a suitable solution. The ``cnpg`` plugin implements the ``pgadmin4`` command, providing a straightforward method to connect to a given database ``Cluster`` and navigate its content in a local environment such as ``kind`` . For example, you can install a demo deployment of pgAdmin4 for the ``cluster-example`` cluster as follows: .. code:: sh kubectl cnpg pgadmin4 cluster-example This command will produce: .. code:: output ConfigMap/cluster-example-pgadmin4 created Deployment/cluster-example-pgadmin4 created Service/cluster-example-pgadmin4 created Secret/cluster-example-pgadmin4 created [...] After deploying pgAdmin, forward the port using kubectl and connect through your browser by following the on-screen instructions. .. figure:: /images/pgadmin4.png :width: 70% :alt: Screenshot of desktop installation of pgAdmin Screenshot of desktop installation of pgAdmin As usual, you can use the ``--dry-run`` option to generate the YAML file: .. code:: sh kubectl cnpg pgadmin4 --dry-run cluster-example pgAdmin4 can be installed in either desktop or server mode, with the default being server. In ``server`` mode, authentication is required using a randomly generated password, and users must manually specify the database to connect to. On the other hand, ``desktop`` mode initiates a pgAdmin web interface without requiring authentication. It automatically connects to the ``app`` database as the ``app`` user, making it ideal for quick demos, such as on a local deployment using ``kind`` : .. code:: sh kubectl cnpg pgadmin4 --mode desktop cluster-example After concluding your demo, ensure the termination of the pgAdmin deployment by executing: .. code:: sh kubectl cnpg pgadmin4 --dry-run cluster-example | kubectl delete -f - .. Warning:: Never deploy pgAdmin in production using the plugin. 　 Logical Replication Publications ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ The ``cnpg publication`` command group is designed to streamline the creation and removal of `PostgreSQL logical replication publications `_ . Be aware that these commands are primarily intended for assisting in the creation of logical replication publications, particularly on remote PostgreSQL databases. .. Warning:: It is crucial to have a solid understanding of both the capabilities and limitations of PostgreSQL's native logical replication system before using these commands. In particular, be mindful of the `logical replication restrictions `_ . 　 Creating a new publication ^^^^^^^^^^^^^^^^^^^^^^^^^^ To create a logical replication publication, use the ``cnpg publication create`` command. The basic structure of this command is as follows: .. code:: sh kubectl cnpg publication create \ --publication PUBLICATION_NAME \ [--external-cluster EXTERNAL_CLUSTER] LOCAL_CLUSTER [options] There are two primary use cases: - With ``--external-cluster`` : Use this option to create a publication on an external cluster (i.e. defined in the ``externalClusters`` stanza). The commands will be issued from the ``LOCAL_CLUSTER`` , but the publication will be for the data in ``EXTERNAL_CLUSTER`` . - Without ``--external-cluster`` : Use this option to create a publication in the ``LOCAL_CLUSTER`` PostgreSQL ``Cluster`` (by default, the ``app`` database). .. Warning:: When connecting to an external cluster, ensure that the specified user has sufficient permissions to execute the `CREATE PUBLICATION` command. 　 You have several options, similar to the `CREATE PUBLICATION `_ command, to define the group of tables to replicate. Notable options include: - If you specify the ``--all-tables`` option, you create a publication ``FOR ALL TABLES`` . - Alternatively, you can specify multiple occurrences of: - ``--table`` : Add a specific table (with an expression) to the publication. - ``--schema`` : Include all tables in the specified database schema (available from PostgreSQL 15). The ``--dry-run`` option enables you to preview the SQL commands that the plugin will execute. For additional information and detailed instructions, type the following command: .. code:: sh kubectl cnpg publication create --help Example ''''''' Given a ``source-cluster`` and a ``destination-cluster`` , we would like to create a publication for the data on ``source-cluster`` . The ``destination-cluster`` has an entry in the ``externalClusters`` stanza pointing to ``source-cluster`` . We can run: .. code:: sh kubectl cnpg publication create destination-cluster \ --external-cluster=source-cluster --all-tables which will create a publication for all tables on ``source-cluster`` , running the SQL commands on the ``destination-cluster`` . Or instead, we can run: .. code:: sh kubectl cnpg publication create source-cluster \ --publication=app --all-tables which will create a publication named ``app`` for all the tables in the ``source-cluster`` , running the SQL commands on the source cluster. .. Note:: There are two sample files that have been provided for illustration and inspiration: `logical-source `_ and `logical-destination `_ . 　 Dropping a publication ^^^^^^^^^^^^^^^^^^^^^^ The ``cnpg publication drop`` command seamlessly complements the ``create`` command by offering similar key options, including the publication name, cluster name, and an optional external cluster. You can drop a ``PUBLICATION`` with the following command structure: .. code:: sh kubectl cnpg publication drop \ --publication PUBLICATION_NAME \ [--external-cluster EXTERNAL_CLUSTER] LOCAL_CLUSTER [options] To access further details and precise instructions, use the following command: .. code:: sh kubectl cnpg publication drop --help Logical Replication Subscriptions ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ The ``cnpg subscription`` command group is a dedicated set of commands designed to simplify the creation and removal of `PostgreSQL logical replication subscriptions `_ . These commands are specifically crafted to aid in the establishment of logical replication subscriptions, especially when dealing with remote PostgreSQL databases. .. Warning:: Before using these commands, it is essential to have a comprehensive understanding of both the capabilities and limitations of PostgreSQL's native logical replication system. In particular, be mindful of the `logical replication restrictions `_ . 　 In addition to subscription management, we provide a helpful command for synchronizing all sequences from the source cluster. While its applicability may vary, this command can be particularly useful in scenarios involving major upgrades or data import from remote servers. Creating a new subscription ^^^^^^^^^^^^^^^^^^^^^^^^^^^ To create a logical replication subscription, use the ``cnpg subscription create`` command. The basic structure of this command is as follows: .. code:: sh kubectl cnpg subscription create \ --subscription SUBSCRIPTION_NAME \ --publication PUBLICATION_NAME \ --external-cluster EXTERNAL_CLUSTER \ LOCAL_CLUSTER [options] This command configures a subscription directed towards the specified publication in the designated external cluster, as defined in the ``externalClusters`` stanza of the ``LOCAL_CLUSTER`` . For additional information and detailed instructions, type the following command: .. code:: sh kubectl cnpg subscription create --help .. _example-1: Example ''''''' As in the section on publications, we have a ``source-cluster`` and a ``destination-cluster`` , and we have already created a publication called ``app`` . The following command: .. code:: sh kubectl cnpg subscription create destination-cluster \ --external-cluster=source-cluster \ --publication=app --subscription=app will create a subscription for ``app`` on the destination cluster. .. Warning:: Prioritize testing subscriptions in a non-production environment to ensure their effectiveness and identify any potential issues before implementing them in a production setting. 　 .. Note:: There are two sample files that have been provided for illustration and inspiration: `logical-source `_ and `logical-destination `_ . 　 Dropping a subscription ^^^^^^^^^^^^^^^^^^^^^^^ The ``cnpg subscription drop`` command seamlessly complements the ``create`` command. You can drop a ``SUBSCRIPTION`` with the following command structure: .. code:: sh kubectl cnpg subcription drop \ --subscription SUBSCRIPTION_NAME \ LOCAL_CLUSTER [options] To access further details and precise instructions, use the following command: .. code:: sh kubectl cnpg subscription drop --help Synchronizing sequences ^^^^^^^^^^^^^^^^^^^^^^^ One notable constraint of PostgreSQL logical replication, implemented through publications and subscriptions, is the lack of sequence synchronization. This becomes particularly relevant when utilizing logical replication for live database migration, especially to a higher version of PostgreSQL. A crucial step in this process involves updating sequences before transitioning applications to the new database (*cutover*). To address this limitation, the ``cnpg subscription sync-sequences`` command offers a solution. This command establishes a connection with the source database, retrieves all relevant sequences, and subsequently updates local sequences with matching identities (based on database schema and sequence name). You can use the command as shown below: .. code:: sh kubectl cnpg subscription sync-sequences \ --subscription SUBSCRIPTION_NAME \ LOCAL_CLUSTER For comprehensive details and specific instructions, utilize the following command: .. code:: sh kubectl cnpg subscription sync-sequences --help .. _example-2: Example ''''''' As in the previous sections for publication and subscription, we have a ``source-cluster`` and a ``destination-cluster`` . The publication and the subscription, both called ``app`` , are already present. The following command will synchronize the sequences involved in the ``app`` subscription, from the source cluster into the destination cluster. .. code:: sh kubectl cnpg subscription sync-sequences destination-cluster \ --subscription=app .. Warning:: Prioritize testing subscriptions in a non-production environment to guarantee their effectiveness and detect any potential issues before deploying them in a production setting. 　 Integration with K9s -------------------- The ``cnpg`` plugin can be easily integrated in `K9s `_ , a popular terminal-based UI to interact with Kubernetes clusters. See :ref:`k9s/plugins.yml ` for details. Permissions required by the plugin ---------------------------------- The plugin requires a set of Kubernetes permissions that depends on the command to execute. These permissions may affect resources and sub-resources like Pods, PDBs, PVCs, and enable actions like ``get`` , ``delete`` , ``patch`` . The following table contains the full details: .. csv-table:: :header: Command,Resource Permissions :widths: 10,30 :align: left :class: longtable backup,clusters: get backups: create certificate,"clusters: get secrets: get,create" destroy,"pods: get,delete jobs: delete,list PVCs: list,delete,update" fencing,"clusters: get,patch pods: get" fio,PVCs: create configmaps: create deployment: create hibernate,"clusters: get,patch,delete pods: list,get,delete pods/exec: create jobs: list PVCs: get,list,update,patch,delete" install,none logs,clusters: get pods: list pods/log: get maintenance,"clusters: get,patch,list" pgadmin4,clusters: get configmaps: create deployments: create services: create secrets: create pgbench,clusters: get jobs: create promote,clusters: get clusters/status: patch pods: get psql,"pods: get,list pods/exec: create" publication,"clusters: get pods: get,list pods/exec: create" reload,"clusters: get,patch" report cluster,clusters: get pods: list pods/log: get jobs: list events: list PVCs: list report operator,**Required:** deployments: get **Optional (for full report):** configmaps: get events: list pods: list pods/log: get secrets: get services: get mutatingwebhookconfigurations: list[^1] validatingwebhookconfigurations: list[^1] **If OLM is present:** clusterserviceversions: list[^1] installplans: list[^1] subscriptions: list[^1] restart,"clusters: get,patch pods: get,delete" status,clusters: get pods: list pods/exec: create pods/proxy: create PDBs: list objectstores.barmancloud.cnpg.io: get subscription,"clusters: get pods: get,list pods/exec: create" version,none ///Footnotes Go Here/// Additionally, assigning the ``list`` permission on the ``clusters`` will enable autocompletion for multiple commands. Role examples ^^^^^^^^^^^^^ It is possible to create roles with restricted permissions. The following example creates a role that only has access to the cluster logs: .. code:: yaml - -- apiVersion: rbac.authorization.k8s.io/v1 kind: Role metadata: name: cnpg-log rules: - verbs: - get apiGroups: - postgresql.cnpg.io resources: - clusters - verbs: - list apiGroups: - resources: - pods - verbs: - get apiGroups: - resources: - pods/log The next example shows a role with the minimal permissions required to get the cluster status using the plugin’s ``status`` command: .. code:: yaml apiVersion: rbac.authorization.k8s.io/v1 kind: Role metadata: name: cnpg-status rules: - verbs: - get apiGroups: - postgresql.cnpg.io resources: - clusters - verbs: - list apiGroups: - resources: - pods - verbs: - create apiGroups: - resources: - pods/exec - verbs: - create apiGroups: - resources: - pods/proxy - verbs: - list apiGroups: - policy resources: - poddisruptionbudgets - verbs: - get apiGroups: - barmancloud.cnpg.io resources: - objectstores .. Note:: Keeping the verbs restricted per `resources` and per `apiGroups` helps to prevent inadvertently granting more than intended permissions.