Linux IP Masquerade HOWTO - The Linux Documentation Project

HOWTO. Please see the this FAQ section in the HOWTO for additional
information.
* IP: ip fwmark masq−forwarding support (EXPERIMENTAL) (CONFIG_IP_MASQUERADE_MFW) [Y/m/n/?] y
− OPTIONAL: This is a NEW method of performing PORTFW−like functionality which is
similar to how the new 2.4.x kernels do things. With this option, IPCHAINS
can mark packets that should have additional work done upon it. Using a
UserSpace tool, much like IPMASQADM or IPPORFW, IPCHAINS would then
do things like re−address the packets, change their TOS value, etc.
Currently, this code is less tested than PORTFW but it looks promising.
For now, this HOWTO recommends to use IPMASQADM and IPPORTFW. If you
have specific thoughts or comments on MFW, please email dranch.
* IP: optimize as a router not host (CONFIG_IP_ROUTER) [Y/n/?] y
− YES: This optimizes the kernel for the network subsystem, though it
isn't well known if this makes a siginificant performance difference
or not.
== Non−MASQ options skipped
== ( autoconf, tunneling, GRE )
* IP: multicast routing (CONFIG_IP_MROUTE) [N/y/?] n
− OPTIONAL: Though not needed for IPMASQ, enabling this feature will
let you route multicast traffic through your Linux box.
Please note that this requires that your ISP be multicast
enabled as well.
== Non−MASQ options skipped
== (Aliasing, ARPd)
* IP: TCP syncookie support (disabled per default) (CONFIG_SYN_COOKIES) [Y/n/?]
− YES: Recommended : for basic TCP/IP network security
* IP: GRE tunnels over IP (CONFIG_NET_IPGRE) [N/y/m/?]
− NO: This OPTIONAL selection is to enable PPTP and GRE tunnels through
the IP MASQ box
== Non−MASQ options skipped
== (aliasing, ARPd)
* IP: TCP syncookie support (not enabled per default) (CONFIG_SYN_COOKIES) [Y/n/?]
− YES: HIGHLY recommended for basic TCP/IP network security
== Non−MASQ options skipped
== (RARP)
* IP: Allow large windows (not recommended if