How does the NFSv4 grace periods work?
- ONTAP 9
- NFSv4 and NFSv4.1
There are two NFSv4 related grace periods:
- When an interface is moved to another node, NFSv4 clients can reclaim locks for the duration specified by the
- When an aggregate is relocated to another node, NLM lock reclamation takes place for the duration specified by the
locking.grace_lease_secondsnode option. The NFSv3 accessing will be affected by this as well.
During either of these periods, NFSv4 clients cannot obtain new locks.
- After a takeover, the two periods may overlap.
- On a giveback, interfaces are reverted before aggregates are relocated and both periods may be observed individually.
- Depending on the timing of how clients retry NFS calls, client applications may experience longer I/O delays than the grace periods themselves.