Fix NFS errors in VM

Are you on a VPN?

Using Cisco AnyConnect will prevent Vagrant from mounting your shared folders in the developer VM. If your VM is already running, it will freeze if you attempt to access a shared folder.

To prevent this, start your VM with the command VAGRANT_GOVUK_NFS=no vagrant up.

This will use a less efficient method of sharing folders, but it will work with the VPN.

Once you disconnect from the VPN, you will need to run these commands before you’re able to use Vagrant with NFS again.

Vagrant error NFS is reporting that your exports file is invalid

==> default: Exporting NFS shared folders...
NFS is reporting that your exports file is invalid. Vagrant does
this check before making any changes to the file. Please correct
the issues below and execute "vagrant reload":

exports:2: path contains non-directory or non-existent components: /Users/<username>/path/to/vagrant
exports:2: no usable directories in export entry
exports:2: using fallback (marked offline): /
exports:5: path contains non-directory or non-existent components: /Users/<username>/path/to/vagrant
exports:5: no usable directories in export entry
exports:5: using fallback (marked offline): /

This means that you may already have old Vagrant path definitions in your /etc/exports file.

Try opening up /etc/exports file to identify old or unwanted Vagrant paths and removing them if necessary.

On opening /etc/exports file each set begins with # VAGRANT-BEGIN: and ends with # VAGRANT-END:. Make sure to delete these and any other lines between VAGRANT-BEGIN: and VAGRANT-END:

or maybe

sudo rm /etc/exports
sudo touch /etc/exports

vagrant halt
vagrant up

Permission denied errors on synced folders

If your host is running macOS 10.12 Sierra you may encounter this problem as there is a bug in the NFS implementation that means the cache is not updated frequently enough. The usual way of encountering this problem is early in a govuk_puppet run, it will fail early with a Permission Denied error when trying to remove a file in vendor/modules/. One workaround is to remove the vendor/modules and .tmp folders from your govuk-puppet working directory on your host, and then run govuk_puppet again in the VM.

The other solution, as mentioned in this GitHub issue against Vagrant is to force macOS to refresh the NFS cache. To do this on your host you run

ls -alR > /dev/null

in the root of your govuk folder. To do this on your VM you run

find /var/govuk -type d -exec touch '{}'/.touch ';' -exec rm -f '{}'/.touch ';' 2>/dev/null

These two options have been provided as shell scripts in the govuk-puppet/development-vm folder:

• refresh-nfs-cache-on-host.sh - run this on your host machine to perform the ls command above on ../../ which should be the checkout location of all your repos.
• refresh-nfs-cache-on-vm.sh - run this on your VM to perform the find command above on /var/govuk.
• vagrant-up.sh - run this on your host to refresh the cache and then bring up your vagrant VM.