mmafmconfig command

Can be used to manage home caching behavior and mapping of gateways and home NFS exported servers.

Synopsis

You can use the mmafmconfig command to -
  • set up or update mapping for parallel data transfers by using add, update, or delete options.
  • enable or disable extended attributes/sparse file support from the AFM cache.
mmafmconfig {add | update} MapName --export-map ExportServerMap

or

mmafmconfig delete {MapName | all}

or

mmafmconfig show [MapName | all]

or

mmafmconfig {enable | disable} ExportPath

Availability

Available with IBM Spectrum Scale™ Standard Edition or higher. Available on AIX® and Linux.

Description

You can use this command to configure a home cluster for enabling support of extended attributes /sparse files on AFM cache filesets pointing to this home. You must run the mmafmconfig enable command on the home path. Running this command creates the .afm directory which contains the control-enabled, directio .afmctl file. The mmafmconfig disable command removes the .afm directory from the home path and subsequently, the cache does not support sparse files and files with extended attributes.

You can also use the mmafmconfig command with add, update, delete, or show options on the cache site to manage mapping of gateway node with home NFS servers for parallel data transfers.

Ensure that you run mmafmconfig enable at home fileset before the cache fileset is linked. As an administrator, if you run this command at home after linking fileset at cache, unlink and relink fileset at cache.

Parameters

MapName
Specifies the name that uniquely identifies the mapping of the gateway nodes with the home NFS exported servers.
--export-map ExportServerMap
Specifies a comma-separated list of pairs of home NFS exported server nodes (ExportServer) and gateway nodes (GatewayNode), in the following format: 
[ExportServer/GatewayNode][,ExportServer/GatewayNode][,...]
where:
ExportServer
Is the IP address or host name of a member node in the home cluster MapName.
GatewayNode
Specifies a gateway node in the cache cluster (the cluster where the command is issued).
enable
Enables extended attributes or sparse files functions on the AFM cache. Run at the home cluster only.
disable
Disables extended attributes or sparse files functions on the AFM cache. Run at the home cluster only.
ExportPath
Specifies the root of the home exported directory for enabling or disabling the AFM features.
add
Sets up maps for parallel data transfers. Run at cache only.
delete
Deletes maps for parallel data transfers. Run at cache only.
update
Updates maps for parallel data transfers. Run at cache only.

Exit status

0
Successful completion.
nonzero
A failure has occurred.

Security

You must have root authority to run the mmafmconfig command.

The node on which the command is issued must be able to execute remote shell commands on any other node in the cluster without the use of a password and without producing any extraneous messages. For more information, see Requirements for administering a GPFS file system.

Example

The following is an example of a mapping for an NFS target, assuming four cache gateway nodes hs22n18, hs22n19, hs22n20, and hs22n21, mapped to two home NFS servers js22n01 and js22n02 (192.168.200.11 and 192.168.200.12) and then creating single writer filesets by using the following mapping:
  1. Issue the following command: 
    # mmafmconfig add mapping1 --export-map js22n01/hs22n18,js22n02/hs22n19
    The system displays output similar to: mmafmconfig: Command successfully completed.
  2. Issue the following command: 
     # mmafmconfig add mapping2 --export-map js22n02/hs22n20,js22n01/hs22n21
    The system displays output similar to: mmafmconfig: Command successfully completed.

    mmafmconfig: Propagating the cluster configuration data to all affected nodes. This is an asynchronous process.

  3. Issue the following command: 
    # mmafmconfig show
    The system displays output similar to: Map name: mapping1

    Export server map: 192.168.200.12/hs22n19.gpfs.net,192.168.200.11/hs22n18.gpfs.net

    Map name: mapping2

    Export server map: 192.168.200.11/hs22n20.gpfs.net,192.168.200.12/hs22n21.gpfs.net

  4. #Create filesets using these mappings:

    Issue the following commands: mmcrfileset gpfs1 sw1 –inode-space new –p afmmode=sw,afmtarget=mapping1://gpfs/gpfs2/swhome

    mmcrfileset gpfs1 ro1 –inode-space new –p afmmode=ro,afmtarget=mapping2://gpfs/gpfs2/swhome

See also

Location

/usr/lpp/mmfs/bin

Parent topic: Command reference