Policies used for monitoring AFM and AFM DR

You can monitor AFM and AFM DR using some policies and commands.

Following are the policies used for monitoring:

The following file attributes are available through the policy engine:

Table 1. Attributes with their description
Attribute	Description
P	The file is managed by AFM and AFM DR.
u	The file is managed by AFM and AFM DR, and the file is fully cached. When a file originates at the home, it indicates that the entire file is copied from the home cluster.
v	A file or a soft link is newly created, but not copied to the home cluster.
w	The file has outstanding data updates.
x	A hard link is newly created, but not copied to the home cluster.
y	A file metadata was changed and the change not copied to the home cluster.
z	A file is local to the cache and is not queued at the home cluster.
j	A file is appended, but not copied to the home cluster. This attribute also indicates complete directories.
k	All files and directories that are not orphan and are repaired.

A list of dirty files in the cache cluster:
This is an example of a LIST policy that generates a list of files in the cache with pending changes that have not been copied to the home cluster.
```
RULE 'listall' list 'all-files' SHOW( varchar(kb_allocated) || ' ' || varchar(file_size) || ' ' || 
          varchar(misc_attributes) || ' ' || fileset_name) WHERE REGEX(misc_attributes,'[P]') AND 
          REGEX(misc_attributes,'[w|v|x|y|j]')
```
If there are no outstanding updates, an output file is not created.
A list of partially cached files:
The following example is that of a LIST policy that generates a list of partially-cached files. If the file is in progress, partial caching is enabled or the home cluster becomes unavailable before the file is completely copied.
```
RULE 'listall' list 'all-files'
          SHOW(varchar(kb_allocated) || ' ' || varchar(file_size) || ' ' || 
          varchar(misc_attributes) || ' ' || fileset_name )
          WHERE REGEX(misc_attributes,'[P]') AND NOT REGEX(misc_attributes,'[u]') AND kb_allocated > 0 
```
This list does not include files that are not cached. If partially-cached files do not exist, an output file is not created
The custom eviction policy:
The steps to use policies for AFM file eviction are - generate a list of files and run the eviction. This policy lists all the files that are managed by AFM are not accessed in the last seven days.
```
RULE 'prefetch-list' 
          LIST 'toevict' 
          WHERE CURRENT_TIMESTAMP - ACCESS_TIME > INTERVAL '7' DAYS 
          AND REGEX(misc_attributes,'[P]') /* only list AFM managed files */
```
To limit the scope of the policy or to use it on different filesets run mmapplypolicy by using a directory path instead of a file system name. /usr/lpp/mmfs/bin/mmapplypolicy $path -f $localworkdir -s $localworkdir -P $sharedworkdir/${policy} -I defer
Use mmafmctl to evict the files: mmafmctl datafs evict --list-file $localworkdir/list.evict

A policy of uncached files:

The following example is of a LIST policy that generates a list of uncached files in the cache directory:

RULE EXTERNAL LIST 'u_list'
         RULE 'u_Rule' LIST 'u_list' DIRECTORIES_PLUS FOR FILESET ('sw1') WHERE NOT 
         REGEX(misc_attributes,'[u]')

An example of a LIST policy that generates a list of files with size and attributes belonging to the cache fileset is as under - (cacheFset1 is the name of the cache fileset in the example.)
```
RULE 'all' LIST 'allfiles' FOR FILESET ('cacheFset1') SHOW( '/' || VARCHAR(kb_allocated) 
|| '/' || varchar(file_size) || '/' || 
VARCHAR(BLOCKSIZE) || '/' || VARCHAR(MISC_ATTRIBUTES) )
```