Setting up subnets and routing

Configuring gated on a router

The behavior of the gated routing daemon is configured using the file /etc/inet/gated.conf. To create this file, you will need the following information:

For an external router, the ID of your Automonous System (AS ID). See ``Understanding Autonomous Systems -- exterior and interior routers'' for information on acquiring an autonomous system ID number.
The protocol(s) to be used.
The exterior and interior gateways with which the router will be exchanging routing or reachability information.
The filtering to be used for an external router, for example, to control which ASs should be excluded.

Examine the information provided for each protocol that you wish to support from the sample protocol configuration files provided with your TCP/IP software distribution. The four protocols and their related sample configuration files are:

Protocol Filename

EGP /etc/inet/gated.egp

BGP /etc/inet/gated.bgp

RIP /etc/inet/gated.rip

OSPF /etc/inet/gated.ospf

Read the gated.conf(4tcp) manual page carefully while examining these files. Using the provided files as a model, copy the appropriate statements into the gated.conf file and tailor them to your site requirements. Note that comments in the configuration file begin with a number sign (#) and statements are terminated with a semicolon (;). Also, the options, interface, definition, protocol, route, and control statements must be specified in the order just listed.

Protocol	Filename
EGP	/etc/inet/gated.egp
BGP	/etc/inet/gated.bgp
RIP	/etc/inet/gated.rip
OSPF	/etc/inet/gated.ospf

NOTE: If the /etc/inet/gated.conf file does not exist, routed is started as the gateway daemon instead of gated the next time your host reboots.

When first enabling gated, you should execute it with the -n option to ensure that it does not modify the kernel routing table. To do this:

Amend the entry that starts gated in /etc/inet/config to read:
```
sort-key:/usr/sbin/in.gated::y:/etc/inet/gated.conf:-n:
```
Shut down and reboot the system.

When you have finished testing the gateway and are satisfied that it is working correctly, you can run gated without the -n option. To do this:

Amend the entry that starts gated in /etc/inet/config to read:
```
sort-key:/usr/sbin/in.gated::y:/etc/inet/gated.conf::
```
Shut down and reboot the system.

If you subsequently change the /etc/inet/gated.conf file, and gated is already running, enter the command gdc reconfig to have gated re-read the file without shutting down either the daemon or the system.