For anyone else running into problems with Trellis on Big Sur here is a setup that finally worked for me. I’ve had so much trouble getting Trellis to work smoothly after an involuntary upgrade to Big Sur.
Most of the time it would just error with a vague mount nfs not supported error.
Still not sure where the exact problem lies. I’ve been trying to find the problem or similar solutions.
Here is what’s working for me (after trying a lot of different combinations of versions):
Make sure FileVault is disabled on the directory your projects are located in. I disabled FileVault entirely.
Make sure you’ve edited
/etc/sudoers with the things here https://www.vagrantup.com/docs/synced-folders/nfs
Unfortunately I think you have to re-create the box with
vagrant destroy /
vagrant up if you downgrade versions. So make sure you do a backup of the data you need before.