Changing replication options

Content Platform Tenant Management Help

Version
9.7.x
File Size
4269 KB
Audience
anonymous
Part Number
MK-95HCPH002-19

You can enable or disable replication for a namespace on the namespace Replication panel. While replication is enabled for the namespace, you can change options that relate to replication. While replication is disabled for the namespace, these options are hidden.

The replication options you can change are:

  • Read from remote system.

    By default, when you create a namespace, this option is enabled.

    Important: Do not disable the read-from-remote-system option unless you have a specific reason to do so.
  • Accept REST, S3 compatible requests redirected from other HCP systems.

    By default, when you create a namespace, this option is enabled.

    You may want to disable this option if your applications cannot tolerate stale data or metadata. One way to get stale data would be to request an object for which two versions exist but for which the current version hasn’t been replicated yet. In this case, the system targeted by the request would retrieve the old version from another system in the replication topology and return that version to the application.

  • Collision handling.

    By default, when you create a namespace, this option is set to move objects.

  • Allow erasure coding.

    If allowed by the tenant configuration and if you make the namespace cloud optimized, when you create a namespace, you can choose whether the namespace allows erasure coding.

    Allowing erasure coding for a namespace that has shredding enabled as the default for new objects can significantly increase the load on all systems in the replication topology.

    You can also enable or disable replication for namespaces and, if allowed, manage erasure coding on the Replication page.

    While the tenant is being replicated, if you disable replication for a namespace that has already been replicated and then delete the namespace on one or more systems, the namespace deletions are not replicated. If you then reenable replication for that namespace and the namespace still exists on one or more systems, the namespace is replicated back to the systems where you deleted it.

    Important: Disabling replication or the read-from-remote-system option for a namespace that has already been replicated may cause object data in that namespace to become inaccessible on one or more systems in the replication topology.
  • To view the replication options for a namespace, you need the monitor or administrator role.
  • To change the replication options for a namespace, you need the administrator role.
  1. In the top-level menu of the Tenant Management Console, click Namespaces.
  2. In the list of namespaces, click the namespace you want.
  3. In the row of tabs below the namespace name, click Services.
  4. On the left side of the Services panel, click Replication.
  5. To enable or disable replication, select or deselect Replication.
  6. (Optional) If Enable replication is selected, take one or more of these actions:
    • To enable or disable the read-from-remote-system feature, select or deselect Enable read from remote system.
    • To allow or disallow HCP to service redirected REST, S3 compatible requests that target the namespace, select or deselect Accept requests redirected from other systems in the replication topology.
    • For cloud-optimized namespaces only, to allow or disallow erasure coding for the namespace, select or deselect Allow erasure coding.
    • To change the collision handling option, click Collision Handling. Then, in the Collision Handling section:
      • To have HCP move objects flagged as replication collisions to the .lost+found directory, select Move object to the .lost+found directory.
      • To have HCP rename objects flagged as replication collisions, select Rename object and store in the same location.
  7. Click Update Settings.
    Note: Removing a tenant from an Active-Passive replication link on the Active site followed by its deletion from the Passive site can result in lost data if, in the future, an Active/Active replication link is created between the same clusters and the same tenant is added to that link.