Start VPN on demand

Hi folks,

I'm using vpnc on my laptop to connect to a cisco vpn server. I don't
need the link very often, and currently I start/stop it in a command
line window. However, I'd prefer to do this automatically: is there any
way of being able to bring up the link on demand?

I guess the general question is whether it's possible to watch for
packets to certain addresses and if matched, to run a program.

I've considered writing a shell script based around either tcpdump, or
a DROP/LOG rule in iptables, but before I go down that route I thought
it would be more sensible to ask here. After all, I don't really wnat
to reinvent the wheel.

Thanks,
Chris

chris-(E-Mail Removed) écrivait news:cl4v13-(E-Mail Removed):

> line window. However, I'd prefer to do this automatically: is there any
> way of being able to bring up the link on demand?

May I suggest you DIALD :

http://diald.sourceforge.net/

Regards

chris-(E-Mail Removed) écrivait news:cl4v13-(E-Mail Removed):
> line window. However, I'd prefer to do this automatically: is there any
> way of being able to bring up the link on demand?

In uk.comp.os.linux Antoine EMERIT <(E-Mail Removed)> wrote:
> May I suggest you DIALD :
> http://diald.sourceforge.net/

Thanks for the pointer. (I've not used diald for ages, and had forgotten
all about it.)

I've been reading and trying, reading and trying, and still reading and
trying,... but still cannot work out how to run an "arbitrary" program
when diald detects packets on the link.

Essentially, I want to run "vpnc-connect" when packets are seen from
my network 192.168.130.0/24 are destined for 10.100.0.0/16, and after
a specified timeout (maybe 10 minutes) to drop the link by running
"vpnc-disconnect"

Any suggestions, please?

Thanks,
Chris