H3C S5120-EI Series, Руководство по эксплуатации

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IP Routing Overview
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Routing
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Routing Protocol Overview
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Displaying and Maintaining a Routing Table
The term “router” in this document refers to a router in a generic sense or a Layer 3 switch.
Routing
Routing in the Internet is achieved through routers. Upon receiving a packet, a router finds an optimal
route based on the destination address and forwards the packet to the next router in the path until the
packet reaches the last router, which forwards the packet to the intended destination host.
Routing provides the path information that guides the forwarding of packets.
Routing Table and FIB Table
Routing table
Routing tables play a key role in routing.route selection and forwarding information bases (FIBs) play a
key role in packet forwarding. Each router maintains a routing table, and each entry in the table
specifies which physical interface a packet destined for a certain destination should go out to reach the
next hop (the next router) or the directly connected destinationFIB table at least.
Routes in a routing table can be divided into three categories by origin:
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Direct routes: Routes discovered by data link protocols, also known as interface routes.
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Static routes: Routes that are manually configured.
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Dynamic routes: Routes that are discovered dynamically by routing protocols.
Dynamic routing protocol is not supported on the S5120-EI Series Ethernet Switches.
Each entry in the FIB table specifies which physical interface a packet destined for a certain destination
should go out to reach the next hop (the next router) or the directly connected destination.