Hi, have a 2600+ running latest 2.5.9_UK firmware.

I'm trying to set-up a rule that will block all outbound traffic on port 25 but it just does not seem work! Any advise would be very much appreciated as I'm just going round in circles....

Under the firewall general set-up the Data Filter is enabled and is set to start with filter set Set#2.

I have set-up a Filter Rule (number 2) under the default data filter of xNetBios -> DNS.

Check to enable The Filter Rule = CHECKED
Pass or Block = Block Immediately
Branch to Other Filter Set = None
Direction = OUT
Protocol = TCP

Source IP = any
Subnet Mask = 255.255.255.0 (/24)
Operator = "="
Start Port = 25
End Port = LEFT EMPTY

Dest IP = any
Subnet Mask = 255.255.255.0 (/24)
Operator = "="
Start Port = 25
End Port = LEFT EMPTY

Keep State = UNCHECKED
Fragments = Don't care

However I am still able to telnet to an external mailserver on port 25!!!

Thanks in advance!

(a very frustrated) Adam

change:

source ip = your lan range
source port = 1024 - 65635
protocol = tcp

destination port = 25 - 25
protocl = tcp

your issue is with your source ports. they do not connect FROM 25 but from a range of 1024 and above.

eg 1024 > 25 or 1025 > 25 etc etc

*** be aware, you will block ALL communication to ALL mail servers with the above rule from anywhere on your lan ***

sorted. great thanks!!