As illustrated by
``Direct routing example'',
and
``Indirect routing example'',
the successful routing of IP packets depends on the contents of the
kernel routing table.
Entries in the kernel routing table are created, removed, and changed:
automatically when running the Network Configuration Manager
to configure or remove a network interface.
When configuring a network interface you are prompted for
an IP address and netmask.
This information is used to create a routing table entry with the
network attached to the interface as the destination field in the
routing table.
Through this process, the machine always knows about the networks
to which it is directly connected.
manually through use of the
route(ADMN)
command.
Through this command, the kernel routing table can contain
entries for networks to which the machine is not directly connected.
On small, static networks, manual maintenance of the kernel routing
table with the route command is reasonable, requiring less
computer overhead than using routing daemons.
dynamically by routing daemons running on the machine.
A routing daemon communicates via routing protocols with the routing
daemons on other
machines to learn about the existence of routes other than those
to which the machine is directly connected.
The routing daemon adds entries for these networks to the kernel routing
table automatically.
On large or changing networks, the use of routing daemons reduces
administrative overhead.
A special STREAMS driver handles all updates to and lookups in
the kernel routing table.
This driver and the messages used to communicate with the driver
are described in
route(ADMP).
All SCO TCP/IP commands and routing daemons that need to update
or access data in the kernel routing table use this driver.
More information is provided in the discussion of the routing
daemons (see
``Routing daemons'').