I have
been using CSF firewall for a number of year
s with
all flavours of asterisk and touch wood
none have
ever been compromised. This is not a comp
lete
Guide but will get your system locked
down
Firstly
we need to install Webmin and CSF so log in
to
console.
wget
1.580-1.noarch.rpm
rpm -U
webmin-1.580-1.noarch.rpm
Now we
will do CSF while we are in console.
tar zxf
csf.tgz
cd csf
sh
install.sh
If all
that went smooth we need to now log into Web
min from
your web browser
User will
be root and whatever pass you set
Now we
need to install the CSF Gui into Webmin
Click on
Webmin as seen above, you will then see
Click on
Webmin modules This will allow us to insta
ll module
Click to
browse for the file
If you
wish just copy this path and paste it in /et
c/csf/csfwebmin.tgz
Now just
click install and leave everything as defa
ults,
when done you will now see under system in
Webmin
Click on
Configserver
Now we
get down to the Nitty gritty of setting our
firewall
up, you will need to add your local ip
range
into the allow field and click allow to add i
t
Set
testing to “ 0 “ this will enable the firewall
out of
test mode
Remove
inbound ports in TCP and also UDP leave blan
k, this
will stop anyone connecting to your
system
unless you allow the IP
In UDP
outbound I added 1000:65000 just for ease, i
t doesn’t
really matter as nothing can connect
until I
allow it
Next this
is if you use Dyndns names for remote ext
ensions
with dynamic IP’s , set Dyndns to 300 to
check for
change of address
Also set
DYNDNS_IGNORE
= 1 this
will ignore dyndns names and allow them
through
Next you
really should disable this unless you want
thousand
of emails
Next 1 to
disable is process tracking or you will g
et
flooded with mail
That is
all that is needed to lock down your asteri
sk
system, so any SIP trunks or remote connections
you will
need to add into the allow list
This is a
quick rundown so if anyone finds errors o
r has any
suggestions feel free to contact me and I
will try
to respond when I get some time
dave@itshack.com.au
DaveD
