NFS mounted but shows nothing even df -h has it

Hello,

I have OpenBSD 7.2 installed and NFS service running on Cubieboard2,
one Linux client and one MacOS client, everything works fine for the
last 6 months.

Yesterday as usual I mounted NFS share and showed mounting
successfully even command `df -h` got it, but `ls /Users/jazzi/nfs`
showed nothing. Tried on both Linux and MacOS.

OpenBSD is 24*7 running and I didn't do anything to change the system,
maybe it's too hot so I shut it down for the whole night and power on
the next day but it didn't work.

+++++++++++++++++++++++++++
Here is how I mount it on MacOS:

> sudo mount -t nfs -o resvport,async,nolocks,locallocks,soft,wsize=32768,rsize=32768 192.168.31.231:/mnt/hdd /Users/jazzi/nfs

+++++++++++++++++++++++++++++++++++
Here is the settings on OpenBSD NFS server:

# $ cat /etc/exports

# For Macbook Air
/mnt/hdd -alldirs -mapall=root 192.168.31.76

# For Linux desktop
/mnt/hdd -alldirs -mapall=root 192.168.31.77

############

Any help will be appreciated, thank you.



--
jazzi

Best Regard,