≡ Menu

FreeBSD: IPv6 Configuration Set Prefixlen Value

How do I set the prefixlen for an IPv6 address under FreeBSD operating systems?

You can set the prefixlen for an IPv6 address by editing /etc/rc.conf file, enter:
# vi /etc/rc.conf
Assuming that your IPv6 is address is 2001:48c8:7::2 for em0, enter:

ipv6_ifconfig_em0="2001:48c8:7::2 prefix 64"

Save and close the file. Restart networking. You can also set it at the shell prompt using the ifconfig command as follows:

ifconfig interFace inet6 ipv6IpAddress prefixlen Value
ifconfig fxp0 inet6 2001:48c8:7::2 prefixlen 64


  • fxp0 or em0 – FreeBSD NIC interface name
  • 2001:48c8:7::2 – IPv6 public IP address
  • 64 – IPv6 Prefixlen Value
Share this tutorial on:
{ 0 comments… add one }
Security: Are you a robot or human?

Leave a Comment

You can use these HTML tags and attributes: <strong> <em> <pre> <code> <a href="" title="">

   Tagged with: , , , , , , , , ,