IBM General Parallel File System for AIX: Administration and Programming Reference

Adding disks to a file system

Many files grow rapidly and you may decide that more disk space is required for your file system soon after creation. Before adding disks, see Specifying disk descriptors for details on creating disk descriptors.

Adding disks in an SP environment

To add disks to a file system in an SP environment, you must decide if you will:

1. Create new virtual shared disks via the mmcrvsd command.
2. Create new virtual shared disks with more than one disk via the procedures outlined in the IBM Parallel System Support Programs for AIX: Managing Shared Disks manual.
3. Select virtual shared disks no longer in use in any file system.

The virtual shared disk may then be added to the file system via the mmadddisk command.

For example, to add the virtual shared disk gpfs20vsd to the file system fs1, allowing only data to be written to it, have it join failure group 3, enter:

mmadddisk fs1 gpfs20vsd:::dataOnly:3  

The system displays information similar to:

GPFS: 6027-531 The following disks of fs1 will be formatted on node k145n08:
    gpfs20vsdlv15: size 4390912 KB 
Extending Allocation Map 
GPFS: 6027-1503 Completed adding disks to file system fs1. 
mmadddisk: 6027-1371 Propagating the changes to all affected nodes. 
This is an asynchronous process. 
Restriping fs1 ...
GPFS: 6027-589 Scanning file system metadata, phase 1 ...    
  70 % complete on Wed Aug 16 15:14:28 2000  
 100 % complete on Wed Aug 16 15:14:29 2000 
GPFS: 6027-552 Scan completed successfully. 
GPFS: 6027-589 Scanning file system metadata, phase 2 ...  
GPFS: 6027-552 Scan completed successfully. 
GPFS: 6027-589 Scanning file system metadata, phase 3 ... 
GPFS: 6027-552 Scan completed successfully. 
GPFS: 6027-565 Scanning user file metadata ...    
   6 % complete on Wed Aug 16 15:14:45 2000  
 100 % complete on Wed Aug 16 15:14:46 2000
GPFS:6027-552 Scan completed successfully. 
Done

Adding disks in an HACMP environment

To add disks to a file system in an HACMP environment, you must decide if you will:

1. Create new logical volumes via the mmcrlv command.
2. Select logical volumes no longer in use in any file system.

The disk may then be added to the file system via the mmadddisk command.

Note:

When using Fibre Channel disks, single-node quorum is not supported.

For example, to add the disk gpfslv02 to the file system fs2, allowing default usage of dataAndMetadata, have it join failure group 1, and rebalance the existing files to take advantage of the added space, enter:

mmadddisk  fs2 gpfslv02::::1 -r

The system displays information similar to:

GPFS: 6027-531 The following disks of fs2 will be formatted on node k145n01:
    gpfslv02: size 4390912 KB
Extending Allocation Map
GPFS: 6027-1503 Completed adding disks to file system fs2.
mmadddisk: 6027-1371 Propagating the changes to all affected nodes.
This is an asynchronous process.
Restriping fs2 ...
GPFS: 6027-589 Scanning file system metadata, phase 1 ... 
  70 % complete on Wed Aug 16 15:14:28 2000
 100 % complete on Wed Aug 16 15:14:29 2000
GPFS: 6027-552 Scan completed successfully.
GPFS: 6027-589 Scanning file system metadata, phase 2 ... 
GPFS: 6027-552 Scan completed successfully.
GPFS: 6027-589 Scanning file system metadata, phase 3 ... 
GPFS: 6027-552 Scan completed successfully.
GPFS: 6027-565 Scanning user file metadata ...
   6 % complete on Wed Aug 16 15:14:45 2000
 100 % complete on Wed Aug 16 15:14:46 2000
GPFS: 6027-552 Scan completed successfully.
Done