< Previous  | TOC | Index | Next  >

Directing file allocations

Directing File Allocations shows how you might use the allocation policies to direct file allocations.

Click the thumbnail above to view full-sized image.

The /mnt file system has three volumes in its volume set: vol-01, vol-02, and vol-03. These volumes correspond to policy1, policy2, and policy3, respectively.

 To direct file allocations

1. Create the allocation policies on the /mnt file system.
2. Assign the data and metadata allocation policies to the /mnt file system as policy1 and policy2.
3. Assign the data and metadata allocation policies to dir1 with the INHERIT flag, with both as policy3.
4. Create file4 (100MB), which becomes allocated to vol-02.
5. Create file3 (10MB), which becomes allocated to vol-02.
6. Create file2 (100MB), which becomes allocated to vol-03.
7. Create file1 (100MB), which becomes allocated to vol-03.
8. Assign the data and metadata allocation policies to file4, with both as policy3.
9. Enforce the allocation policies on file4, which reallocates the file to vol-03.

The file system has a policy assignment that allocates data as directed by policy1 and metadata as directed by policy2. These policies cause files to be allocated on vol-01 and vol-02, except for dir1, which has overriding assignments for allocation on vol-03.

When the file3 and file4 files are created, they are allocated on vol-02 as directed by the policy1 and policy2 assignments. When file1 and file2 are created, they are allocated on vol-03, as specified by policy3.

When file4 is created, the initial allocation is on vol-01 and vol-02. To move file4 to vol-03, assign policy3 to file4 and enforce that policy on the file. This reallocates file4 to vol-03.