Update: I have tested this with MacOS Sierra and it works for me!

I forward local ports on my OS X machines using pfctl so that I can use traditional ports for HTTP and HTTPS with Vagrant without having to start vagrant with root privleges. Recently when I updated to OS X El Capitan (10.11) I noticed that my port forwards stopped working.

Previously I had followed some of the steps in this gist, but all of those changes had been wiped out with the upgrade. When I tried to re-apply them, a new feature called System Integrity Protection (SIP) prevented me from editing some necessary files. Also, since all of my changes had been wiped out with this upgrade, I wanted to try to keep my changes out of existing system files as much as possible in the hopes that they won’t be wiped out with the next upgrade.

Creating an anchor file

The first file we need to add is an anchor file. This defines the ports we want to forward. Create the file in /etc/pf.anchors/<CUSTOM NAME>. You can add one or many lines of the following format:

rdr pass on lo0 inet proto tcp from any to any port <SOURCE PORT> -> port <DESTINATION PORT>

Testing the anchor file

To test the anchor file, run the following command.

sudo pfctl -vnf /etc/pf.anchors/<CUSTOM NAME>

The ports won’t actually be forwarded yet, this just checks the validity of your anchor file. If you see output that looks something like the below, with no errors, you’re good.

fctl: Use of -f option, could result in flushing of rules
present in the main ruleset added by the system at startup.
See /etc/pf.conf for further details.

rdr pass on lo0 inet proto tcp from any to any port = <SOURCE PORT> -> port <DESTINATION PORT>

Creating a pfctl config file

Once your anchor file checks out, you need to add a pfctl config file. Create this file under /etc/pf-<CUSTOM NAME>.conf and add the following contents.

rdr-anchor "forwarding"
load anchor "forwarding" from "/etc/pf.anchors/<CUSTOM NAME>"

Testing the config file

You can start pfctl using the below command. This will forward the ports according to your rules.

sudo pfctl -ef /etc/pf-<CUSTOM NAME>.conf

To stop forwarding ports run the same command, replacing the e option with d.

sudo pfctl -df /etc/pf-<CUSTOM NAME>.conf

Forwarding ports at startup

You can use the commands above to start port forwarding on demand if you wish, otherwise if (like me) you want to forward ports automatically at startup you can create a launchctl plist file. Create a file under /Library/LaunchDaemons/com.apple.pfctl-<CUSTOM NAME>.plist with the following contents:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
     <string>com.apple.pfctl-<CUSTOM NAME></string>
          <string>/etc/pf-<CUSTOM NAME>.conf</string>

Add the file to startup using the following command:

sudo launchctl load -w /Library/LaunchDaemons/com.apple.pfctl-<CUSTOM NAME>.plist


You can find an example here that forwards port 80 to 4000 and 443 to 4001.


Hopefully this was helpful. Thanks to kujohn for creating the excellent gist that worked so well for me previously.