If HyperFS will not mount, follow the steps below to get a verbose error message, helping point to the root cause of the issue:

  1. Launch the HyperFS client (from Spotlight search, for example)

  2. Note that a "Mount all" command will not give a verbose error message, instead listing the number of failed exports

  3. To get better error reporting, start by double-clicking the IP address of the server

  4. Try to mount a single export (such as with Right Click > "Mount")

  5. Note the error that comes up, and find the corresponding article from the list below

HyperFS client error messages:

Make sure all storage devices are connected

Not all storage LUNs can be found. Troubleshoot the iSCSI or fibre channel connection.

The application is abnormal. Try again.

The RPC port needs to be changed from 2049 to 2050. Full article.

Service is busy or has no response. Make sure service works well and try again. 

The macOS and HyperFS client version is incompatible (consult HyperFS compatibility page) or kext needs to be loaded (troubleshooting guide here).