Backing up database data (OCP)

You can back up (and later restore) existing topology data for the Agile Service Manager OCP installation. This can be helpful when updating your system, as part of your company's data management best-practice, or for maintenance reasons.

Preparing your system for backup

1. Authenticate into the Kubernetes namespace where Agile Service Manager is deployed as part of your solution.
2. Deploy the following kPodLoop bash shell function.
   kPodLoop is a bash shell function that allows a command to be run against all the matching Kubernetes containers. You can copy it into the shell.

   kPodLoop() {
    __podPattern=$1
    __podCommand=$2
    __podList=$( kubectl get pods --field-selector=status.phase=Running --no-headers=true --output=custom-columns=NAME:.metadata.name | grep ${__podPattern} )
    printf "Pods found: $(echo -n ${__podList})\n"
    for pod in ${__podList}; do
       printf "\n===== EXECUTING COMMAND in pod: %-42s =====\n" ${pod}
       kubectl exec ${pod} -- bash -c "${__podCommand}"
       printf '_%.0s' {1..80}
       printf "\n"
    done;
   }
   

   This kPodLoop bash shell function filters the pods to run the commands against only those that are in a 'Running' phase. This filter ensures that the configuration pods that are only run as part of your installation, like the secret generator pod, are skipped.
3. Make a note of the scaling of Agile Service Manager pods.

   kubectl get pods --field-selector=status.phase=Running --no-headers=true --output=custom-columns=CNAME:.metadata.ownerReferences[0].name | grep topology | uniq --count

   Example output:

   1 noi-topology-dns-observer
   1 noi-topology-docker-observer
   3 noi-topology-elasticsearch
   1 noi-topology-file-observer
   1 noi-topology-kubernetes-observer
   1 noi-topology-layout
   1 noi-topology-merge
   1 noi-topology-noi-gateway
   1 noi-topology-noi-probe
   1 noi-topology-observer-service
   1 noi-topology-search
   1 noi-topology-status
   1 noi-topology-topology
   1 noi-topology-ui-api
   

4. Verify access to each Cassandra database (this command will return a list of keyspaces from each Cassandra node). Adjust the Cassandra pod names based on your deployment model naming convention.

   kPodLoop noi-cassandra "cqlsh -u \${CASSANDRA_USER} -p \${CASSANDRA_PASS} -e \"DESC KEYSPACES;\""
   

5. Scale down Agile Service Manager pods.

   kubectl scale deployment --replicas=0 noi-topology-dns-observer
   kubectl scale deployment --replicas=0 noi-topology-file-observer
   kubectl scale deployment --replicas=0 noi-topology-kubernetes-observer
   kubectl scale deployment --replicas=0 noi-topology-observer-service
   kubectl scale deployment --replicas=0 noi-topology-noi-gateway
   kubectl scale deployment --replicas=0 noi-topology-noi-probe
   kubectl scale deployment --replicas=0 noi-topology-layout
   kubectl scale deployment --replicas=0 noi-topology-merge
   kubectl scale deployment --replicas=0 noi-topology-status
   kubectl scale deployment --replicas=0 noi-topology-search
   kubectl scale deployment --replicas=0 noi-topology-ui-api
   kubectl scale deployment --replicas=0 noi-topology-topology
   

   The Cassandra and Elasticsearch pods (noi-cassandra and noi-topology-elasticsearch) are left active. Cassandra pods need to be running in order to execute the backup of their data, whereas the ElasticSearch pods have no interaction with nor influence on the Cassandra contents, so can be kept running.

   Important: Include in this scale down any additional observers in your deployment.
6. Verify that scaling down was successful.

   kubectl get pods --field-selector=status.phase=Running  | grep noi-topology

   The Agile Service Manager services have now been scaled down, and the Cassandra database contents will not be modified anymore.

Backing up data

7. Deploy the pbkc bash shell function.
   The pbkc function attempts to backup the Cassandra database on all nodes as close to simultaneously as possible. You can copy it into the shell. Modify the following example script and change RELEASE to conform to your installation's Cassandra pod names based on your deployment model naming conventions.

   pbkc() {
    ## Parallel Backup of Kubernetes Cassandra
    RELEASE=noi
   
    DATE=$( date +"%F-%H-%M-%S" )
    LOGFILEBASE=/tmp/clusteredCassandraBackup-${DATE}-
    declare -A LOG
   
    ## get the current list of cassandra pods.
    podlist=$( oc get pods --field-selector=status.phase=Running --no-headers=true --output=custom-columns=NAME:.metadata.name | grep ${RELEASE}-cassandra )
    for pod in ${podlist}; do
     echo -e "BACKING UP CASSANDRA IN POD ${pod}"
     oc exec ${pod} -- bash -c "/opt/ibm/backup_scripts/backup_cassandra.sh -u \${CASSANDRA_USER} -p \${CASSANDRA_PASS} -f > /dev/null 2> /dev/null &"
    done
   
    printf "Waiting for backups to complete:"
   
    COMPLETE="false"
    while [ $COMPLETE = "false" ]; do
     COMPLETE="true"
     for pod in ${podlist}; do
       log=`oc exec $pod -- bash -c "ps -ef | grep backup_cassandra.sh- | grep -v grep | awk '{print \\\$NF}'"`
       if [ $? != 0 ]; then
         COMPLETE="false"
       elif [ -n "$log" ]; then
        COMPLETE="false"
        LOG[$pod]=$log
       fi
     done
     printf "-"
     if [ $COMPLETE = "false" ]; then
       sleep 30
     fi
    done
   
    printf "\n"
   
    for pod in ${podlist}; do
     log=${LOGFILEBASE}${pod}.log
     oc cp ${pod}:${LOG[$pod]} ${log}
     echo -e "Backup of ${pod} completed, please verify via log file ($log)"
    done
   }

8. Run a clean-up on all keyspaces in all Cassandra instances.
   Example Cassandra keyspaces cleanup:

   kPodLoop noi-cassandra "nodetool cleanup system_schema"
   kPodLoop noi-cassandra "nodetool cleanup system"
   kPodLoop noi-cassandra "nodetool cleanup system_distributed"
   kPodLoop noi-cassandra "nodetool cleanup system_auth"
   kPodLoop noi-cassandra "nodetool cleanup janusgraph"
   kPodLoop noi-cassandra "nodetool cleanup system_traces"
   

9. Run backup on all Cassandra instances (using the pbkc shell function just deployed).

   pbkc

10. Check the final output in the log file for each backup.
    Adjust the date in the grep command as appropriate.

    grep  "BACKUP DONE SUCCESSFULLY" /tmp/clusteredCassandraBackup-2019-06-14-14-09-50*
    /tmp/clusteredCassandraBackup-2019-06-14-14-09-50-noi-cassandra-0.log:Fri Jun 14 14:11:04 UTC 2019 BACKUP DONE SUCCESSFULLY !!!
    /tmp/clusteredCassandraBackup-2019-06-14-14-09-50-noi-cassandra-1.log:Fri Jun 14 14:11:16 UTC 2019 BACKUP DONE SUCCESSFULLY !!!
    /tmp/clusteredCassandraBackup-2019-06-14-14-09-50-noi-cassandra-2.log:Fri Jun 14 14:11:16 UTC 2019 BACKUP DONE SUCCESSFULLY !!!
    

    Tip: For additional information about backing up secrets and the system_auth keyspace, see the Secrets and system_auth keyspace note in the 'Restoring database data (OCP)' topic.
    When backup has successfully completed, you restore your Agile Service Manager services to normal operation.

Restore services

11. Scale up the services to the original level.
    The original level was obtained in a previous step.

    kubectl scale deployment --replicas=1 noi-topology-topology
    kubectl scale deployment --replicas=1 noi-topology-layout
    kubectl scale deployment --replicas=1 noi-topology-merge
    kubectl scale deployment --replicas=1 noi-topology-status
    kubectl scale deployment --replicas=1 noi-topology-search
    kubectl scale deployment --replicas=1 noi-topology-observer-service
    kubectl scale deployment --replicas=1 noi-topology-noi-gateway
    kubectl scale deployment --replicas=1 noi-topology-noi-probe
    kubectl scale deployment --replicas=1 noi-topology-ui-api
    kubectl scale deployment --replicas=1 noi-topology-dns-observer
    kubectl scale deployment --replicas=1 noi-topology-file-observer
    kubectl scale deployment --replicas=1 noi-topology-rest-observer
    kubectl scale deployment --replicas=1 noi-topology-kubernetes-observer