8.9. Creating Distributed Striped Replicated Volumes

Important

Distributed-Striped-Replicated volume is a technology preview feature. Technology Preview features are not fully supported under Red Hat subscription level agreements (SLAs), may not be functionally complete, and are not intended for production use. However, these features provide early access to upcoming product innovations, enabling customers to test functionality and provide feedback during the development process.
Distributed striped replicated volumes distributes striped data across replicated bricks in the trusted storage pool. For best results, you should use distributed striped replicated volumes in highly concurrent environments where parallel access of very large files and performance is critical. In this release, configuration of this volume type is supported only for Map Reduce workloads.

Note

The number of bricks should be a multiples of number of stripe count and replica count for a distributed striped replicated volume.
Illustration of a Distributed Striped Replicated Volume

Figure 8.7. Illustration of a Distributed Striped Replicated Volume


To create a distributed striped replicated volume
  1. Create a trusted storage pool as described earlier in Section 7.1, “Adding Servers to Trusted Storage Pool”.
  2. Create a distributed striped replicated volume using the following command:
    # gluster volume create NEW-VOLNAME [stripe COUNT] [replica COUNT] [transport tcp | rdma | tcp,rdma] NEW-BRICK...
    For example, to create a distributed replicated striped volume across eight storage servers:
    # gluster volume create test-volume stripe 2 replica 2 transport tcp server1:/exp1 server1:/exp2 server2:/exp3 server2:/exp4 server3:/exp5 server3:/exp6 server4:/exp7 server4:/exp8
    Creation of test-volume has been successful
    Please start the volume to access data.
    The order in which the bricks are specified determines the mirroring of bricks with each other. For example, first n bricks, where n is the replica count. Hence, the first two bricks specified will mirror each other, and the third and fourth bricks will mirror each other.
    If the transport type is not specified, tcp is used as the default. You can also set additional options if required, such as auth.allow or auth.reject. For more information, see Section 10.1, “Tuning Volume Options”

    Note

    Make sure you start your volumes before you try to mount them or else client operations after the mount will hang, see Section 8.10, “Starting Volumes ” for details.