Re: RHEL3 ES: problem with demand dialing...

Jean-David Beyer wrote:
> I have setup my new computer, running Red Hat Enterprise Linux 3 ES,
> to do demand dialing since it serves two other machines and all must
> share the same dialup line.
> 
> It is set to start at boot, but to drop the connection every time 600
>  seconds go by with no transmission. (Spammers can keep the
> connection up by sending me a spam every 590 seconds, and I see this
> happen sometimes).
> 
I do not have the original problem solved, but the spammers and probers 
are keeping the link up for hours at a time. So I have been trying to 
fix that.

Right now I am stuck. I looked at the man page for pppd and the 
_active-filter_ option looks about what I need. I wish I did not need to 
"duplicate" some of my firewall rules in there: there should be means to 
say not to count as traffic anything dropped by iptables, but that is 
not how it is.

Now the _active-filter_ option of pppd says it requires that both the 
kernel and pppd be built with *PPP_FILTER* defined. Examining 
/boot/config-2.4.21-9.0.1.ELsmp shows that the kernel is OK:

CONFIG_PPP_FILTER=y

I do not know how to tell with pppd, so I recompiled it from source, and 
now it does not seem to complain about the existance of the 
_active-filter_ option, but I cannot make it work.

In my /etc/sysconfig/network-scripts/ifcfg."ppp0" script, I have tried 
all manner of ways to get the option string in, all to no avail. File 
/usr/share/doc/initscripts-*/sysconfig.txt states that the way to get 
options into PPPD is to include this in the 
/etc/sysconfig/network-scripts/ifcfg."ppp0" script,

PPPOPTIONS=<arbitrary option string; is placed last on the
       command line, so it can override other options like asyncmap
       that were specified differently>

but no matter what choices I have made for single and double quoting 
things, I cannot get it to take anything even as simple as

PPPOPTIONS="active-filter dst host 123.456.789.012"

[IP address obscured here.]

Can anyone give the proper syntax for this? Or is the problem elsewhere? 
I really do not want to leave the connection up for hours just because 
of the incessant probing of my machine by @$$y9o3w.

-- 
   .~.  Jean-David Beyer           Registered Linux User 85642.
   /V\                             Registered Machine   241939.
  /( )\ Shrewsbury, New Jersey     http://counter.li.org
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