OSX NFS serving to Arch VirtualBox guest

11 Feb 2015 #Columbia #nfs #osx #virtualbox

For Operating Systems we’re using Arch Linux in a VirtualBox guest. One of the issues is dealing with storing code, etc, in a robust way so that it’s easy to work with, and allows you to freely take and restore snapshots without losing work. I first tried using VirtualBox Shared Folders, but they were a real pain in the ass, and apparently don’t work well with permissios and symlinks.

Instead I setup NFS, hosting a directory on my OSX laptop and mounting it inside the virtual machine. I sent some instructions out to students based on my recollection of how to do it, but I haven’t directly tested them. Still, I figured they might be helpful if you came across this page by google searching for something!


I actually ended up using NFS to share files between my mac and virtual machine. I mount a folder in my home directory and put all my work in there, so if I need to restore a snapshot I never need to worry about losing my work. It took a little bit of work, but wasn’t too hard. I mostly sort of followed these directions: http://blog.hostilefork.com/sharing-nfs-into-virtualbox/ along with https://wiki.archlinux.org/index.php/NFS.

On OSX: {.p1}

1) edit /etc/exports to add a line like:

/Users/clm2186/Documents/Columbia/Current/COMS4118/ -alldirs

The above serves my OS directory and all subdirectories only to localhost. Be super careful about the, there are other options with using netmasks and stuff, but you can potentially expose your files to almost anyone if you’re not cautious.

2?) I think I had to edit


to add a line at the end in ProgramArguments for -N. However now I can’t figure out why I did it, or if I really needed to.


3) Start up nfsd: sudo nfsd enable

4) Look in Console.app for all the errors, try to fix them. sudo nfsd restart after tweaking /etc/exports.

5) You can try mounting the share by going into finder -> Go -> Connect to Server and using the url:


9) run id to get the uid (mine was 501) and gid (20)

Here’s my recollection of the VM side steps: {.p1}

10) Take a snapshot of your VM

11) Install NFS:

 sudo pacman -S nfs-utils

12) Create another admin user, or make sure you know the root password. I think sudo passwd should change it if you need to.

12) reboot VM

13) sign into root user (or another admin user that can sudo)

14) change the userid of your main user to match the OSX partition (Per the end of http://blog.hostilefork.com/sharing-nfs-into-virtualbox/)

 usermod -u [ID] [username]. 

15) I also changed the groupid, but I doubt it matters much.

16) Sign into your user account

17) We need to make a directory for mounting the nfs share:

 mkdir ~/osnfs 

18) edit /etc/hosts to add a DNS lookup for the host OSX side:      osxhost

18a) You can figure it out by looking up your gateway inside arch with `ip route show` and looking at the via line

18) Now edit /etc/fstab to add the mapping from nfs to ~/osnfs:

 host:/Users/clm2186/Documents/Columbia/Current/COMS4118 /home/clm2186/osnfs nfs rsize=16384,wsize=16384,timeo=14,nolock,_netdev 0 0

#note, if you have a space in the NFS path use \040, which is the ASCII value of space in octal…

19) then finally you’re ready to mount it!!!

 sudo mount ~/osnfs

20) Once you get it working, probably take a snapshot.

The only known issue I have is that I seem to need to manually mount it with `sudo mount ~/osnfs` every time I reboot.

Ok, I just realized I said this wasn’t that bad, and it’s like 20 crazy steps. However, it really wasn’t too bad, and could be done in probably only 30 minutes if you do it cleanly.   It wasn’t nearly as bad as what doing this sort of thing can become: http://xkcd.com/349/