Monitoring AFM
Active File Management (AFM) enables sharing of data across clusters, even if the networks are unreliable or have high latency.
An AFM fileset can be enabled on a GPFS-independent fileset. Each fileset has a distinct set of AFM attributes. IBM Spectrum Scale cluster that contains AFM filesets is called a cache cluster. A cache cluster has a relationship with another remote site called the home, where either the cache or the home can be the data source or destination.
AFM constantly maintains an active relationship between the cache and the home. Changes are managed per fileset results in modular, scalable architecture capable of supporting billions of files and peta bytes of data. Each AFM-enabled fileset is associated with a single home path.
AFM uses an NFSv3 or NSD (GPFS multi-cluster) protocol for the communication between the home and cache sites. A home export path is either an NFSv3 exported path or a multi-cluster or remote file system, which is mounted at the IBM Spectrum Scale cache cluster. This path is used by an AFM or AFM-DR fileset as a target path for data synchronization between sites. For AFM RO-mode filesets, the target path at the home NFS server can be exported as 'Read-Only' or 'Read/Write'. However, for AFM LU/SW/IW and AFM-DR mode filesets, the target NFS export path must be 'Read/Write'.
Please follow the AFM configuration instructions for setting up a home and a cache cluster.
As a result of the setup activities you should have the nfs exports configured on a home cluster
[root@home-11 ~]# mmnfs export list
Path Delegations Clients
------------------------- ----------- -------
/gpfs/myAFMfs/myAFMfset NONE *
/gpfs/myAFMfs1/myAFMfset1 NONE *
/gpfs/myAFMfs1/myAFMfset2 NONE *
Also make sure the NFS performance sensors are enabled. For more info please read the Activate NFS performance monitoring sensors article in the IBM Spectrum Scale Knowledge Center.
On a cache cluster side you should have cache filesets created TBD
[root@cache-21 ~]# mmafmctl myCacheAFMfs getstate
Fileset Name Fileset Target Cache State Gateway Node Queue Length Queue numExec
------------ -------------- ------------- ------------ ------------ -------------
myCacheAFMfset_independent2 nfs://home-15/gpfs/myAFMfs1/myAFMfset1 Dirty cache-21 16759 1805838
myCacheAFMfset_readOnly nfs://home-14/gpfs/myAFMfs/myAFMfset Active cache-21 0 910783
myCacheAFMfset_writer nfs://home-13/gpfs/myAFMfs1/myAFMfset2 Dirty cache-21 87560 6443545
[root@cache-21 ~]# mmafmctl myCacheAFMfs1 getstate
Fileset Name Fileset Target Cache State Gateway Node Queue Length Queue numExec
------------ -------------- ------------- ------------ ------------ -------------
myCacheAFMfset_independent1 nfs://home-15/gpfs/myAFMfs1/myAFMfset1 Active cache-25 0 372297
