It specifies a SOURCE network for DNAT rules and a DESTINATON network for SNAT rules. NET3 (Optional) - network-address Added in Shorewall 4.4.11. NETMAP is a new implementation of the SNAT and DNAT targets. NET2 - network-address Network in CIDR format Commercial products based on Linux, iptables and netfilter 326. For example, ppp0 in this file will match a m shorewall-interfacesm (8) entry that defines ppp+. Shorewall allows loose matches to wildcard entries in m shorewall-interfacesm (5). The interface must be defined in m shorewall-interfacesm (5). INTERFACE - interface The name of a network interface. Someday, when IPv6 is widely implemented, we can say good-bye to NAT, except for those times when we really want it.
If SNAT, traffic leaving INTERFACE with a source address in NET1 has it's source address rewritten to the corresponding address in NET2. Destination NAT (DNAT) rewrites the destination address, which is the firewall address, to the real server addresses, then iptables forwards incoming traffic to these servers. The important rules regarding NAT are - not very surprising - found in the 'nat'-table. We will use the command utility 'iptables' to create complex rules for modification and filtering of packets. The module also introduces the firewallchain resource, which allows you to manage chains or firewall. This framework enables a Linux machine with an appropriate number of network cards (interfaces) to become a router capable of NAT. I -insert Add a rule to a chain at a given position. D -delete Remove specified rules from a chain. C -check Look for a rule that matches the chain’s requirements. If DNAT, traffic entering INTERFACE and addressed to NET1 has its destination address rewritten to the corresponding address in NET2. This module offers support for iptables and ip6tables. Here is a list of some common iptables options: -A -append Add a rule to a chain (at the end). To use this file, your kernel and iptables must have NETMAP support included. NAME netmap - Shorewall NETMAP definition file SYNOPSIS /etc/shorewall/netmap DESCRIPTION This file is used to map addresses in one network to corresponding addresses in a second network.
0 kommentar(er)
