IPv6 Certification Walkthrough – Administrator-level, Hurricane Electric (part 4)

IPv6 Certification Walkthrough – Administrator-level, Hurricane Electric (part 4)

Step-by-step Instructions

Edit the Postfix Config File

Luckily, OS X is essentially a server operation system, but by default the server-like features are disabled.  We have already enabled the Web server and now it is time to turn on the mail server.  To do this, you will need to adjust some settings in a config file and then turn the service on with a Terminal command.

  1. Open /etc/postfix/main.cf  in a text editor
  2. Make the following changes:
#myhostname = host.domain.tld
#myhostname = virtual.domain.tld
myhostname = mx.jakesalmela.com

#mydomain = domain.tld
mydomain = jakesalmela.com

mydestination = $myhostname, localhost.$mydomain, localhost, $mydomain,

inet_protocols = ipv6
inet_interfaces = all

Start Postfix (Your New Mail Server) from Terminal

sudo postfix start

Test that you Can Connect to Port 25 from Terminal

telnet localhost 25

If you see output saying …connected to host … you should be good to go.  Then exit out.


As an alternative, you can also try typing

netstat -an | grep LISTEN | grep ".25"

to verify functionally.  If you get a result withLISTENING , it should be working.

Forward SMTP Traffic to your Computer

Your mail server is working now, but no one will be able to reach it over IPv6 until you make it available to the Internet.  This is done via port forwarding, just like when the Web server was set up, except this time, it needs to be a different port number.

1. Log into your router

2. Search for a setting called Port Forwarding or Virtual Server

3. Enter your private IPv4 address

4. Enter or choose port 25 (smtp traffic)

Some routers will have common services in a list, which will populate the fields for you.  See the options on my router below:

5. Choose TCP if there is an option for it

6. Click Save or Enable

Create An MX Record So HE Can Find Your New Mail Server

Now that your server is up and running, we need to tell HE how to find it.  This is done by creating an MX DNS record.

  1. Navigate to dns.he.net
  2. Click the button next to your domain to edit the DNS records
  3. Click New MX
  4. Enter your domain information

There should now be a AAAA and an MX record in the zone

Ask HE to Email You At Your New IPv6 Server

DNS can sometimes take a little time to replicate across the Internet, so if it doesn’t work right away, just wait a little bit before trying again.

  1. Navigate to ipv6.he.net
  2. Enter your username@yourdomain.com (find your username by typing whoami in the Terminal)
  3. Click Send it!

Check Your Email To Find the Verification Code


There should be a line reading:

N     1     ipv6@he.net           Sun Nov  3 09:41  26/893   "IPv6 Certification Administrator Mail Test"

Type 1  and press Enter to read the mail.  Copy the code from the body of the email to your clipboard.

Paste the Verification Code Into the Field on HE’s Site to Verify That You Are Running the Server They Just Sent An Email To

1. Navigate back to ipv6.he.net

2. Paste the code into the field and click Submit

3. Answer the test questions to complete the level and earn the certification