Vagrant Centos 8 with nfs - System hangs on any sync folder operation

Question

Vagrant 2.2.18

Modules vagrant-timezone (1.3.0, global) vagrant-vbguest (0.30.0, global)

Host Macbook Pro with Montery, but also seen on Windows 11

Issue: When I do a vagrant up, it seems to load fine and gets past the "Mounting NFS shared folders..." output line fine too. At the end of my Vagrantfile is a path to a provision shell script that does a bunch of setup on the Guest. This also starts to run fine without error.

When it gets to a part of that script that simply copies conf files from the share directory to various locations (such as copying an apache conf to /etc/httpd/conf.d/), the whole process stalls. No error, no timeout, I can leave it for hours and it just stops at simple copy commands.

I can vagrant ssh to the VM and it's responsive, but even doing an ls in / hangs too. It also hangs if I try to cd into /vagrant. But I can ls /etc/httpd/conf.d/ (the file copied by my script is not there).

I'm picking this has something to do with the sync setup. But this was all working fine with a previous centos/7 box. But I have also updated Vagrant and guest additions since then. Can anyone see anything obvious in my Vagrantfile? Anything I could try?

# -*- mode: ruby -*-
# vi: set ft=ruby :

Vagrant.configure("2") do |config|

    config.vm.box = "centos/8"
    config.vm.hostname = "mysite.local"

    # Mount shared folder using NFS
    config.vm.synced_folder ".", "/vagrant",
        id: "core",
        :nfs => true,
        :mount_options => ['rw', 'vers=3', 'tcp', 'fsc', 'actimeo=2']

    # The IP address of the VM
    config.vm.network "private_network", ip: "192.168.100.130"

    # Port forwarding for database. You can now connect to the VM DB using 'localhost' and port 65433
    config.vm.network "forwarded_port", guest: 5432, host: 65434

    # Assign a quarter of host memory and all available CPU's to VM
    # Depending on host OS this has to be done differently.
    config.vm.provider :virtualbox do |vb|
        host = RbConfig::CONFIG['host_os']

        # Mac
        if host =~ /darwin/
            cpus = `sysctl -n hw.ncpu`.to_i
            mem = `sysctl -n hw.memsize`.to_i / 1024 / 1024 / 4

        # Nix
        elsif host =~ /linux/
            cpus = `nproc`.to_i
            mem = `grep 'MemTotal' /proc/meminfo | sed -e 's/MemTotal://' -e 's/ kB//'`.to_i / 1024 / 4

        # Windows...
        else
            cpus = 4
            mem = 2048
        end

        vb.customize ["modifyvm", :id, "--memory", mem]
        vb.customize ["modifyvm", :id, "--cpus", cpus]
        vb.customize ["modifyvm", :id, "--audio", "none"]
        vb.customize ["guestproperty", "set", :id, "/VirtualBox/GuestAdd/VBoxService/--timesync-set-threshold", 1000]
    end

    if Vagrant.has_plugin?("vagrant-vbguest")
        config.vbguest.auto_update = false
    end

    # BOOTSTRAP - The OS/Environment
    config.vm.provision :shell, :path => "Vagrant.bootstrap.sh"

end