Parsing Syslog and Acting on it, using other input too

shawn wilson at
Fri Aug 30 15:17:37 UTC 2013

Ah it seems they do:

IDK enough about fail2ban to know whether I can assign a per proto or per
log type config (I assume I can). In which casethis does what my script
does and then some. I would probably dump out a ipset save on exit and try
to 'restore' on resume (which /I/ do) and I'm sure there's a way fail2ban
can check a store of addresses and check what network a host belongs to
(instead of just a host).

So, fail2ban is probably the way to go.

On Fri, Aug 30, 2013 at 10:00 AM, Christopher Morrow <
morrowc.lists at> wrote:

> On Fri, Aug 30, 2013 at 8:55 AM, Shawn Wilson < at> wrote:
> >
> >
> > Christopher Morrow <morrowc.lists at> wrote:
> >>On Thu, Aug 29, 2013 at 10:50 AM, Don Wilder <don.wilder at>
> >>wrote:
> >>> I wrote a script in Linux that watches for unauthorized login
> >>attempts and
> >>> adds the ip address to the blocked list in my firewall. You might
> >>want to
> >>> search sourceforge for a DYN Firewall and modify it from there.
> >>>
> >>
> >>because fail2ban was too hard to install? or because you just wanted
> >>to test yourself?
> >
> > Actually I did the same. I use ipset lists (generally with a timeout)
> and take a regex or two and black / white list from a YAML file and just
> take (possibly multiple inputs) from piping tail -F. I also store addresses
> for future reference (by the script or otherwise).
> >
> > This is quite maintainable as I can look at a list of people who have
> attacked the mail server and compare it to web attacks. Each process is a
> different type of service (different config file) and probably a different
> ipset. Due to ipset not actually doing anything until I make an iptables
> rule for it, I can run my script in a test mode (by default) and just see
> what happens (check it's logs and the ipset list it generates). I haven't
> found the need for this yet but I can use cymru to look up how big their
> net is (see geocidr for an example of how to do this in perl) and use a
> hash:net ipset type and cover a whole net.
> >
> > Basically what I'm saying in doing it this way is quite expandable and
> isn't very hard and I can do tons of stuff that fail2ban can't (I don't
> think - it's been a while since I looked).
> you seem to be describing what fail2ban does... that and some grep of
> syslog for fail2ban messages. If your solution works then great! :)

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