User`s manual

IA260-261-262 EM-2260 LX User’s Manual Managing Communications
The IA260/IA261/IA262/EM-2260 supports the following sub-modules. Be sure to use the module
that matches your application.
ip_queue ipt_REDIRECT ipt_ah iptable_filter
ip_tables ipt_REJECT ipt_ecn iptable_mangle
ipt_CLUSTERIP ipt_SAME ipt_iprange iptable_nat
ipt_ECN ipt_TOS ipt_owner iptable_raw
ipt_LOG ipt_TTL ipt_recent
ipt_MASQUERADE ipt_ULOG ipt_tos
ipt_NETMAP ipt_addrtype ipt_ttl
NOTE The IA260/IA261/IA262/EM-2260 does NOT support IPv6 and ipchains.
The basic syntax to enable and load an IPTABLES module is as follows:
#lsmod
#modprobe ip_tables
#modprobe iptable_filter
Use lsmod to check if the ip_tables module has already been loaded in the
IA260/IA261/IA262/EM-2260. Use
modprobe to insert and enable the module.
Use the following command to load the modules (iptable_filter, iptable_mangle, iptable_nat):
#modprobe iptable_filter
NOTE IPTABLES plays the role of packet filtering or NAT. Take care when setting up the IPTABLES
rules. If the rules are not correct, remote hosts that connect via a LAN or PPP may be denied
access. We recommend using the Serial Console to set up the IPTABLES.
Click on the following links for more information about iptables.
http://www.linuxguruz.com/iptables/
http://www.netfilter.org/documentation/HOWTO//packet-filtering-HOWTO.html
Since the IPTABLES command is very complex, to illustrate the IPTABLES syntax we have
divided our discussion of the various rules into three categories: Observe and erase chain rules,
Define policy rules, and Append or delete rules.
Observe and erase chain rules
Usage:
# iptables [-t tables] [-L] [-n]
-t tables: Table to manipulate (default: ‘filter’); example: nat or filter.
-L [chain]: List List all rules in selected chains. If no chain is selected, all chains are listed.
-n: Numeric output of addresses and ports.
# iptables [-t tables] [-FXZ]
-F: Flush the selected chain (all the chains in the table if none is listed).
-X: Delete the specified user-defined chain.
-Z: Set the packet and byte counters in all chains to zero.
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