Modifying a Volume

You can edit a volume through MCS and using the CLI.

Modifying a Volume Using the MapR Control System

To modify a volume:

  1. Log in to MCS and go to the volume information page.
  2. Click Edit Volume to display the Edit Volume page.
  3. Modify one or more of the following general, auditing, and replication settings:
    SETTINGS Accountable Entity The entity accountable for the volume’s usage.
    Volume Access Indicates whether volume is a read-only or read/write volume.
    Topology The location of this volume in the cluster rack topology.
    AUDITING Audit Indicates whether auditing of operations on directories, files, and tables in the volumes is enabled.
    Coalesce Interval Interval of time used when logging multiple instance of an operation on a node from a client IP, if auditing is enabled.
    REPLICATION Replication Desired and minimum number of copies of the volumes.
    Name Container Replication Desired and minimum number of copies of the name container associated with the volumes.
    Guarantee Min Replication (Available from v6.0.1) Specifies whether (true) or not (false) to enforce minimum number of copies for the (read-write) volume. If this is enabled (Yes), writes succeed only when the minimum number of copies exist.
    Note: If this parameter was not already set on a volume or if you modify the setting for this property from No to Yes, restart all the nodes where the containers associated with the volume exist for the changes to take effect.
    SETTINGS Source Cluster Name The name of the cluster on which the source volume exists.
    Source Volume Name The name of the source volume to mirror.
    Accountable Entity The entity accountable for this volume’s usage.
    Topology The location of this volume in the cluster rack topology.
    AUDITING Audit Specifies whether auditing of operations on directories, files, and tables in the volumes is enabled.
    Coalesce Interval Interval of time used when logging multiple instance of an operation on a node from a client IP, if auditing is enabled.
    REPLICATION Replication Desired and minimum number of copies of the volumes.
    Name Container Replication Desired and minimum number of copies of the name container associated with the volumes.
    Guarantee Min Replication (Available from v6.0.1) Specifies whether (Yes) or not (No) to enforce minimum number of copies for the (read-write) volume. If this is enabled (Yes), writes succeed only when the minimum number of copies exist.
    Note: If this parameter was not already set on a volume or if you modify the setting for this property from No to Yes, restart all the nodes where the containers associated with the volume exist for the changes to take effect.
  4. Make changes as needed to volume access.
    ADMINISTRATIVE CONTROLS Users and groups that have permissions to perform administrative operations on this volume. To:
    • Modify access to existing users, select or deselect permissions.
    • Grant access to another user, click Add Another, enter the user name, and select permissions to grant to the user.
    USER ACCESS CONTROLS Specifies public or the users, groups, and/or roles that have and/or do not have access to read from and/or write to this volume.
    To grant or block access to users, groups, and/or roles, from the:
    • Basic settings, select the type — public, (OR) user, group, or role — from the drop-down menu, specify the name of the user, group, or role, and select one or more checkbox to grant permissions.
      Tip: Click to create a copy of the associated access control setting. Click to remove the associated access control expression.
      To add access control expressions for another user, group, or role, click Add Another and repeat this step.
    • Advanced settings, or specify public (p) or user (u), group (g), and/or role (r) who have and/or do not have the type of access using the following boolean expressions and subexpressions:
      • ! — Negation operator.
      • & — AND operation.
      • | — OR operation.
      Use (), parentheses, for subexpressions.
      Note: You cannot specify user, group, or role individually if access is granted to all users (public).

      Alternatively, click associated with the type of access to use the Access Control Expression window to define access for public or users, group, and/or role. See Defining ACEs for more information.

    Note: If you switch from Basic to Advanced, the basic settings, if any, will be carried over to the advanced settings. If you switch from Advanced to Basic, all the settings will be lost because the subexpressions and AND (&) and negation (!) operations that are supported by advanced settings are not supported in the basic settings.
  5. (Optional) Modify volume quota as needed.
    Volume Advisory Quota Allocated disk space, which when exceeded raises an alarm but does not prevent writes.
    Volume Hard Quota Allocated disk space, which when exceeded prevents further writes.
  6. (Optional) Add or modify schedule(s) as needed.
    Snapshot Schedule Schedule for creating snapshots of the volume.
    Snapshot Schedule Schedule for creating snapshots of this volume.
    Mirror Schedule Schedule for automatically synchronizing (mirroring) this volume with the source volume.
  7. Click Save Changes for the changes to take effect.

Modifying a Volume Using the CLI or REST API

The basic command to modify a volume is:

maprcli volume modify -name <volume name>

For complete reference information including supported options, see volume modify.