Converting Volume Replication Type (High Throughput to Low Latency) Using the CLI

Lists the process to convert the replication type of a volume using the CLI.

About this task

A low latency replication type allows for volumes to be replicated on multiple containers (in parallel) from the primary container.

NOTE
Contact HPE Data Fabric support before converting volumes to the low_latency replication type.

To convert from a high-throughput to a low-latency replication type:

Procedure

  1. Change the permissions on the volume from read-write to read only.
    For example: 
    maprcli volume modify -name mvol1,mvol2 -readonly true
    Wait for the running operations to complete before proceeding to the next step.
  2. Convert the volume from high_throughput replication type to low_latency replication type using the maprcli command.
    For example: 
    maprcli volume modify -name mvol1,mvol2 -replicationtype low_latency
    Wait till replication type conversion is complete and all the containers of the volume acquire a primary container. If necessary, run the following command to see if replication type has been converted: 
    maprcli volume list -columns ReplTypeConversionInProgress,volumename
    If the conversion is complete, the ReplTypeConversionInProgress flag will be set to false (0). For example, the 0 in the ReplTypeConversionInProgress column in the following sample output indicates successful conversion of corresponding volume in the volumename column: 
    maprcli volume list -columns ReplTypeConversionInProgress,volumename
                        volumename                    ReplTypeConversionInProgress
                        mapr.apps                     0
                        mapr.cldb.internal            0
                        mapr.cluster.root             0
                        mapr.configuration            0
                        mapr.doc22.lab.local.audit    0
                        mapr.doc22.lab.local.logs     0
                        mapr.doc22.lab.local.mapred   0
                        mapr.doc22.lab.local.metrics  0
                        mapr.doc23.lab.local.audit    0
                        mapr.doc23.lab.local.logs     0
                        mapr.doc23.lab.local.mapred   0
                        mapr.doc23.lab.local.metrics  0
                        mapr.hbase                    0
                        mapr.metrics                  0
                        mapr.opt                      0
                        mapr.resourcemanager.volume   0
                        mapr.tmp                      0
                        mapr.var                      0
                        users                         0
  3. Reset the permissions on the volume to read-write.
    For example, to reset, run the following command: 
    maprcli volume modify -name vol1,vol2 -readonly false