# # Shorewall 1.4 - Sample Masquerade file For Two Interfaces # # etc/shorewall/masq # # Use this file to define dynamic NAT (Masquerading) and to define Source NAT # (SNAT). # # Columns are: # # INTERFACE # Outgoing interface. This is usually your internet # interface. If ADD_SNAT_ALIASES=Yes in # /etc/shorewall/shorewall.conf, you may add ":" and # a digit to indicate that you want the alias added with # that name (e.g., eth0:0). This will allow the alias to # be displayed with ifconfig. THAT IS THE ONLY USE FOR # THE ALIAS NAME AND IT MAY NOT APPEAR IN ANY OTHER # PLACE IN YOUR SHOREWALL CONFIGURATION. # # This may be qualified by adding the character # ":" followed by a destination host or subnet. # # # SUBNET # Subnet that you wish to masquerade. You can specify this as # a subnet or as an interface. If you give the name of an # interface, you must have iproute installed and the interface # must be up before you start the firewall. # # In order to exclude a subset of the specified SUBNET, you # may append "!" and a comma-separated list of IP addresses # and/or subnets that you wish to exclude. # # Example: eth1!192.168.1.4,192.168.32.0/27 # # In that example traffic from eth1 would be masqueraded unless # it came from 192.168.1.4 or 196.168.32.0/27 # # ADDRESS (Optional) # If you specify an address here, SNAT will be # used and this will be the source address. If # ADD_SNAT_ALIASES is set to Yes or yes in # /etc/shorewall/shorewall.conf then Shorewall # will automatically add this address to the # INTERFACE named in the first column. # # You may also specify a range of up to 256 IP # addresses if you want the SNAT address to be # assigned from that range in a round robin range # by connection. The range is specified by # -. # # Example: 206.124.146.177-206.124.146.180 # # This column may not contain DNS names. # # Example 1: # # You have a simple masquerading setup where eth0 connects to # a DSL or cable modem and eth1 connects to your local network # with subnet 192.168.0.0/24. # # Your entry in the file can be either: # # #INTERFACE SUBNET ADDRESS # eth0 eth1 # # or # # #INTERFACE SUBNET ADDRESS # eth0 192.168.0.0/24 # # Example 2: # # You add a router to your local network to connect subnet # 192.168.1.0/24 which you also want to masquerade. You then # add a second entry for eth0 to this file: # # #INTERFACE SUBNET ADDRESS # eth0 192.168.1.0/24 # # Example 3: # # You have an IPSEC tunnel through ipsec0 and you want to # masquerade packets coming from 192.168.1.0/24 but only if # these packets are destined for hosts in 10.1.1.0/24: # # #INTERFACE SUBNET ADDRESS # ipsec0:10.1.1.0/24 196.168.1.0/24 # # Example 4: # # You want all outgoing traffic from 192.168.1.0/24 through # eth0 to use source address 206.124.146.176 which is NOT the # primary address of eth0. You want 206.124.146.176 added to # be added to eth0 with name eth0:0. # # #INTERFACE SUBNET ADDRESS # eth0:0 192.168.1.0/24 206.124.146.176 # ############################################################################## #INTERFACE SUBNET ADDRESS eth0 eth1 #LAST LINE -- ADD YOUR ENTRIES ABOVE THIS LINE -- DO NOT REMOVE