Heads up - TAP and TUN changes in master may require a little rejiggering

Matthew Dillon dillon at backplane.com
Fri Aug 2 07:31:28 PDT 2019

For anyone using openvpn or otherwise using TAP and TUN, changes in TAP and
TUN in master may break your systems.  However, they should be easy to
fix.  Basically TAP and TUN no longer pre-create the first four interfaces
(tap0...tap3 and tun0...tun3).  Some application code might depend on
scanning unit numbers to find an available device and no longer work.

These are auto-clone devices, which means that opening "/dev/tap" or
"/dev/tun" automatically creates a new interface.  Not all application code
handles this properly but there is an easier way to deal with these
interfaces and that is to use 'ifconfig tap8 create' or something like that
for tap and tun to pre-create a specific unit, and then specify that
specific device in the application needing it.  "/dev/tap8", etc.

For example:

ifconfig tap8 create

... and in the openvpn configuration one might then specify 'dev tap8'.

If you are running release, this methodology also works the same so you can
get an early start and fixup the system now so it smoothly upgrades to a
new DFly version later on.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.dragonflybsd.org/pipermail/users/attachments/20190802/251703c9/attachment-0001.htm>

More information about the Users mailing list