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- Default route
- Introduction
-
- Once you have fill the "basic host information" form, you _L_i_n_u_x system
- knows how to send packet to other TTCCPP//IIPP on the same network as yours.
- That's it. If you try to send packets to a host (another computer) on
- a different Ethernet network, it won't work unless you tell the system
- which gateway is suitable to reach this other network.
-
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-
- A LAN is generally a set of machines sharing a common Ethernet
- network. Quite often, several separate LANs are connected together
- using one or more routers. One simple and effective router is a _L_i_n_u_x
- system with two Ethernet adaptors.
-
- If there is only one gateway connecting your LAN to other LANs or even
- the _I_n_t_e_r_n_e_t, setting the default route to the IP address of this
- gateway is a safe bet.
-
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-
- If your system is connected to the _I_n_t_e_r_n_e_t using either SSlliipp or PPPPPP,
- then don't set the default route in _L_i_n_u_x_c_o_n_f. Just select the default
- route option of the specific connectivity package you are using (dip,
- pppd, slirp). Those packages will setup the default route when the
- link is up and remove it when it goes down. With PPPPPP, IP numbers are
- often allocated dynamicly from the other side, so you have little idea
- of the gateway IP until the link is up.
-
- On complex networks with many LANs, with many gateway and even
- redundant gateway, your best bet is to use dynamic routing with
- package like routed (supported by _L_i_n_u_x_c_o_n_f) or gated.
-
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-
- The default route is always the last one checked by the kernel. The
- command "nneettssttaatt --nnrr" shows this. So you may set the default route and
- then add route to specific network or host later and these will take
- precedence over the default route.
-
-