FoxGate S63 series, Руководство по настройке

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Routing Protocol Overview
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37.1
Routing Table
As mentioned before, layer3 switch is mainly used to establish the route from the
current layer3 switch to a network or a host, and to forward packets according to the route.
Each layer3 switch has its own route table containing all routes used by that switch. Each
route entry in the route table specifies the physical port should be used for forwarding
packet to reach a destination host or the next hop layer3 switch to the host.
The route table mainly consists of the following:

Destination address: used to identify the destination address or destination
network of an IP packet.

Network mask: used together with destination address to identify the destination
host or the network the layer3 switch resides. Network mask consists of several
consecutive binary 1's, and usually in the format of dotted decimal (an address
consists of 1 to 4 255‘s.) When ―AND‖ the destination address with network mask,
we can get the network address for the destination host or the network the layer3
switch resides. For example, the network address of a host or the segment the
layer3 switch resides with a destination address of 200.1.1.1 and mask
255.255.255.0 is 200.1.1.0.

Output interface: specify the interface of layer3 switch to forward IP packets.

IP address of the next layer3 switch (next hop): specify the next layer3 switch the
IP packet will pass.

Route entry priority: There may be several different next hop routes leading to the
same destination. Those routes may be discovered by different dynamic routing
protocols or static routes manually configured. The entry with the highest priority
(smallest value) becomes the current best route. The user can configure several
routes of different priority to the same destination; layer3 switch will choose one
route for IP packet forwarding according to the priority order.
To prevent too large route table, a default route can be set. Once route table look up
fails, the default route will be chosen for forwarding packets.
The table below describes the routing protocols supported by switch and the default
route look up priority value.
Routing Protocols or route type Default priority value
Direct route 0
OSPF 110
Static route 1
RIP 120
OSPF ASE 150
IBGP 200