ansible-arangodb-operator

Purpose

• Ansible role to deploy ArangoDB Operator in Kubernetes.
• Multiple operators can be deployed in multiple namespaces. Default namespace is: arangodb
• Multiple ArangoDB clusters can be deployed by an operator.

Features

• Downloads manifests from desired release
• Applies user default patches, overriding defaults in original manifests
• Loads resulting manifests in Kubernetes:
  • default: by connecting to the master K8S node via ssh
  • alternatively: provinding local kubernetes config, by setting kubeconfig_file_path
• Instruct operator to deploy cluster(s) and optionally local storages

Dependencies

• Kustomize - will be automatically downloaded in project bin/ directory
• Pip3 packages: see requirements.pip - automatically installed in preflight
• Developed and tested with ansible 2.8, may work with lower/higher versions

Usage

1. Set up your ansible inventory with appropriate hosts and SSH keys:

   • To run remotely:
     • Set your ansible_host in sample-inventory/host_vars/master to point to your kubernetes master
     • Set up your ssh key for authentication to the master
   • To run locally:
     • in sample-inventory/host_vars/master, uncomment: ansible_connection: local
     • set the playbook variable kubeconfig_file_path pointing to a local kubeconfig

2. Set your cluster and deployments options in a vars file (See sample-vars.yml)

3. Run the playbook:

   ANSIBLE_SSH_PIPELINING=true \
   ANSIBLE_CONFIG=sample-ansible.cfg \
   ansible playbook \
       --inventory sample-inventory \
       sample-playbook.yml \
       --extra-vars "@sample-vars.yml"`

   • To skip preflight and speed up a bit, add --skip-tags preflight

Reference

• https://www.arangodb.com/docs/stable/tutorials-kubernetes.html
• https://www.arangodb.com/docs/stable/deployment-kubernetes-deployment-resource.html

ArangoDB Backup & Restore

• 3 types of backups:
  • Physical (raw or “cold”) backups - can be done when the ArangoDB Server is not running
  • Logical backups - arangodump & arangorestore
  • Hot backups - Arangobackup & Hot Backup API - Enterprise Edition only
• Ref: https://www.arangodb.com/docs/stable/backup-restore.html
• Will explain more about the Logical backups method in the following sections

Backup

• By using arangodump, this can be done manually or in a kubernetes CronJob as in the example below

  apiVersion: batch/v1beta1
  kind: CronJob
  metadata:
    labels: {}
    name: "arangodb-backup"
    namespace: <namespace>
  spec:
    schedule: 0 0 * * *
    jobTemplate:
      spec:
        template:
          spec:
            containers:
            - name: arangodb-backup
              image: arangodb:<image_tag>
              command:
              - /bin/sh
              - -c
              args:
              - |-
                arangodump \
                  --server.endpoint "http+tcp://<cluster-exporter-service-name>.<namespace>:8529" \
                  --server.database "<database_name>" \
                  --server.username $DB_USERNAME --server.password $DB_PASSWORD \
                  --output-directory "/backups/<database_name>-`date '+%Y-%m-%d_%H-%M-%S'`" && \
                find /backups/ -mindepth 1 -maxdepth 1 -mtime +7 -type d -exec rm -fvr {} \;
              env:
              - name: DB_USERNAME
                valueFrom:
                  secretKeyRef:
                    key: username
                    name: <arangodb-cluster-root-password-secret>
              - name: DB_PASSWORD
                valueFrom:
                  secretKeyRef:
                    key: password
                    name: <arangodb-cluster-root-password-secret>
              volumeMounts:
              - mountPath: /backups
                name: arangodb-backup-pv
            volumes:
            - name: arangodb-backup-pv
              persistentVolumeClaim:
                claimName: arangodb-backup-pvc
  

  • A persistent volume (arangodb-backup-pv) and a persistent volume claim (arangodb-backup-pvc) should be created for this to work
• This CronJob will perform a daily backup and cleanup, leaving the backups from the last 7 days.
• More details about backup: https://www.arangodb.com/docs/stable/programs-arangodump-examples.html

Restore

• Restoring a database can be done using arangorestore as in the following example:

  arangorestore \
    --server.endpoint "http+tcp://<cluster-exporter-service-name>.<namespace>:8529" \
    --server.database <database_name> \
    --create-database true \
    --server.username <username> \
    --server.password <password> \
    --input-directory <backup_dir_path>
  

• More details about restore: https://www.arangodb.com/docs/stable/programs-arangorestore-examples.html

Variables and parameters

Variable	Default	Description
kustomize_version	3.5.5	Kustomize version to download an use. Kustomize is used locally, even though there is one in the system.
arangodb_operator_version	1.0.2	ArangoDB Operator version (do not put 'v' in front)
arangodb_operator_namespace	arangodb	Operator namespace
arangodb_operator_manifests	[arango-crd.yaml, arango-deployment.yaml, arango-backup.yaml]	List of Kubernetes manifests to download from the operator repo. This should not change normally.
arangodb_operator_manifest_local_storage	arango-storage.yaml	Optional operator local storage manifest. Set to empty to not download it and not use local storage. If empty, arangodb_local_storages will be ignored
arangodb_operator_manifest_replication	arango-deployment-replication.yaml	Optional operator for DC2DC replciation. Set to empty to not download and not use replication
kustomizations.patchesStrategicMerge	[]	List of objects to locate and patch default kubernetes objects in the download manifests. You must specify apiVersion, kind and metadata.name. See: https://github.com/kubernetes-sigs/kustomize/blob/master/docs/plugins/builtins.md#patchesstrategicmerge
kustomizations.patches	[]	List of PatchTransformer objects You must specify kind and name. See: https://github.com/kubernetes-sigs/kustomize/blob/master/docs/plugins/builtins.md#patchtransformer
arangodb_local_storages	[]	Optional list of ArangoLocalStorage. See https://www.arangodb.com/docs/stable/deployment-kubernetes-storage-resource.html
arangodb_clusters	[]	List of ArangoDeployment objects - actual ArangoDB cluster definition. See https://www.arangodb.com/docs/stable/deployment-kubernetes-deployment-resource.html
kubeconfig_file_path		Optional path to Kubernetes admin config file (on the master node is located at /etc/kubernetes/admin.conf). Setting this will not use SSH connection to master, instead try to access the Kubernetes API directly.
kubernetes_operation_retries	20	How many times to retry uploading/waiting for a kubernetes manifest before giving up. Some resources, like Deployments may take longer to be ready.
kubernetes_operation_delay	10	Interval in seconds to retry
kubernetes_ignore_errors	yes	Set to 'no' to fail fast at the first encountered error when trying to create objects in kubernetes

License

MIT