Is it possible to make the PPP device persist, even after losing a
The reason I'd like to do this, is that when the device goes away, all
firewall and routing rules for it are cleaned up by the kernel. The
device completely disappears. If the device later comes back, it will
have lost all of its rules.
Also, having the device stay around would make it easy to avoid
problems trying to chase down ppp0, ppp1, ppp2, etc. during
complicated situations (for example, running a tunnel over a PPPoE DSL
connection, which will require two PPP devices).
Regular Ethernet devices (eth0, eth1, eth2, etc.) are able to survive
a loss of connection, and still maintain their configuration. They
just have their RUNNING flags bit cleared (as visible with
"ifconfig"). Unplug your Ethernet cable right now, and see. When the
connection comes back, the RUNNING flags bit is set again. All of
this without having to redo any firewall or routing rules. In
addition, the counters for statistics are not cleared for the
It would seem to greatly simplify the problems people are having now,
with reliable PPPoE connections, if ppp0 devices could simply have the
same "permanent" status that is given to an eth0 device. The RUNNING
bit could be used from userspace to determine whether or not the
underlying link is connected or disconnected.
Has anybody else considered this, and if so, what was the outcome of
previous discussions? Searching Google didn't seem to find anything
obviously about this.