How are NFS export-policies evaluated in ONTAP 9?

An export-policy is evaluated when a client attempts to access the NFS namespace and no existing access rule has been cached
- During mount, the root volume export-policy is evaluated before the volume or qtree policy
- The volume policy will be evaluated for all access afterward unless it is a qtree, and qtree-exports are enabled
When the policy is evaluated
- The process is iterative and stops on the first match
- When an error occurs in processing a clientmatch, access will be determined by preceding rules only
- Access Cache entries will be created when evaluation completes
- NAS Layer caches will store further Name Service information for the following
  - hostname
  - domain name
  - netgroup
Rules may be ordered to alleviate changes in Name Service availability
- Each of the following groups should be further ordered from most to least restrictive
  1. IP address
  2. subnet
  3. hostname
  4. domain name
  5. netgroup
- The clientmatch field further supports comma-delimited lists of IPs or hostnames
  - Each change in access can be on one line
  - Allows efficient grouping and evaluation for clients with the same access