Editing a Storage Policy

About this task

You can modify the basic rule to:
  • Add or remove users and/or groups.
  • Change the name of the users and/or groups.
  • Change the number of days since the file was last modified for users and/or groups.
If you switch from a basic rule to an advanced rule, all expressions from the basic rule are carried over to the advanced rule. You can modify an advanced rule using a combination of the following expressions:
u Username or user ID, as configured in the OS registry (such as /etc/passwd file, LDAP, etc.), of a specific user.

Usage: u:<username or user ID>
g Group name or group ID, as configured in the OS registry (such as /etc/group file, LDAP, etc.), of a specific group.

Usage: g:<groupname or group ID>
a (atime) Time (in seconds or days) since the files were last accessed. The number of seconds can be specified by appending s to value and the number of days can be specified by appending d to the value.

Usage:

  • "a:<value>s" — specifies atime in seconds
  • "a:<value>d" — specifies atime in days
NOTE: If the system time on CLDB and file server nodes are different, the atime rule for offloading data may not work as intended.

This tier rule is matched and files are offloaded, when all of the following conditions are met:

  1. atime tracking is enabled at volume level
  2. Time since atime that is configured on the volume is more than the time specified in the rule
  3. Duration since the file was last accessed is more than the time specified in the rule

Assume that the atime feature is enabled on the volume and that the time in the rule is set to a:300s. Based on this rule, all files that are not accessed since 300s, are offloaded. However, this rule is valid only if time since atime tracking is enabled, is more than 300s. The volume level parameter atimeTrackingStartTime denotes the start time of atime.

For more information, see Tuning Last Access Time.
m (mtime) Time (in seconds or days) since the files were last modified. The number of seconds can be specified by appending s to value and the number of days can be specified by appending d to the value.

Usage:

  • "m:<value>s" — specifies mtime in seconds
  • "m:<value>d" — specifies mtime in days
All files that are not modified since the specified amount of time, are offloaded.NOTE: If the system time on CLDB and file server nodes are different, the mtime rule for offloading data may not work as intended.
s The size of the file in bytes, kilobytes, megabytes, or gigabytes. The size of the file can be specified by appending one of the following to the value: b for bytes, k for kilobytes, m for megabytes, or g for gigabytes.

Usage

  • "s:<value>b" — specifies file size in bytes
  • "s:<value>k" — specifies file size in KB
  • "s:<value>m" — specifies file size in MB
  • "s:<value>g" — specifies file size in GB
All files whose size exceeds the specified size are offloaded.
Or, use the following:
p (Default) Specifies all files. Specifies that this operation is applicable to all the files without restriction. This cannot be combined with any other operator.
"" Indicates none of the files. Specifies that this operation cannot be performed on any of the files.
Use the following to string multiple criteria for offload:
& AND operation to combine multiple expressions as the criteria for the rule.
| OR operation to indicate either of the expressions as the criteria for the rule.
() Delimiters for subexpressions.

You cannot switch from an advanced rule that includes the following to a basic rule because the following are not supported in a basic rule:

  • p — All the files
  • s — The size of the file
  • & — The AND operation used for specifying multiple users (u), groups (g), or criteria
  • | — The OR operation used with s or m
  • "" — None of the files.
  • () — Subexpressions
NOTE: The basic rule must contain mtime (m). It can also include one or more users or groups separated by the OR operation (|).

Follow the steps given below to edit a storage policy.

Procedure

  1. Log on to the Data Fabric UI.
  2. Click the Fabric administration icon on the left pane.
  3. Select from the Select fabric dropdown the fabric for which you wish to add the storage policy.
  4. Scroll down to the Storage policies card.
    NOTE
    Alternatively, you can click Global namespace, click the fabric link in the table view, and navigate to the Storage policies tab for the fabric.
  5. Click the ellipsis seen under Actions for the storage policy to edit.
  6. Click Edit.
  7. Make the required changes.
  8. Click Save.

Results

The changes to the storage policy are saved successfully.