C-M-G
Series
Manual
© TDT GmbH
Chapter 5: Network Configuration
Seite 57 von 136
5.9.5 Create a new rule
By clicking the
Add Rule
button you can create a new rule within a chain.
Note
IPtables works top-down.
Rules (e.g. Destination NAT) which are defined in section »Pakets before routing
(PREROUTING)«
are
processed
immeditally
an
d
aren’t
passed
over
to
chain »Incoming packets (INPUT)« or other following chains.
For example if a packet is allowed to pass defined through second rule from top and would be
blocked due to third rule from top the packet would be allowed to pass according to second
rule by ignoring third rule.
5.9.5.1 Chain and action details
Command
Description
Part of chain
Defines within which sequencial chain it should be shown
Rule comment
Description of the rule
Action to take
According to the chosen chain type following targets can be
defined:
Do nothing:
no action will be taken
Accept:
the packet will be accepted and processed
Drop:
the packet will be rejected without response
Reject:
the packet will be rejected with response defined
at »Reject with ICMP type«
Userspace:
the packet will be placed in the queue of the user
process
Exit chain:
the sequence chain will be abandoned
Log packet:
logs detailed information about packets to syslog
and continues the chain
Run chain:
the declared sequence chain will be executed
Redirecet:
the packet will be redirected to »Target ports for
redirect«
Destination
NAT:
the packet will be forwarded to »IPs and ports for
DNAT«
Souce NAT:
Source adress will be replaced to values defined
in »IPs and ports for SNAT«
Masquerade:
Source adress will be set to the outgoing
interfaces address
Only in case all in
Condition details
defined parameters match, the chosen action will be
executed. Otherwise the chain will be skiped and the next chain will start.
