Why is the number of routes in the routing table inconsistent with the number of FIB entries after a required route iteration on an S series switches

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Q: Why is the number of routes in the routing table inconsistent with the number of FIB entries after a required route iteration?

A: After routes are iterated as required, routes of multiple outbound interfaces are not generated and there is only one route with multiple outbound interfaces. This route is iterated to multiple routes when delivered to the FIB. As a result, the number of routes in the routing table is inconsistent with the number of FIB entries.
Among the route flags, R indicates that the route is iterated, and D indicates that the route is successfully delivered to the FIB.

Other related questions:
Routing table and FIB table
The functions and meanings of the routing table and FIB table are as follows: Routers forward packets based on routing tables and forwarding information base (FIB) tables. Each router maintains at least one routing table and one FIB table. A routing table stores routes discovered by various routing protocols. Routes are classified into the following types based on the origin: -Direct route: is discovered by link layer protocols. -Static route: is manually configured by network administrators. -Dynamic route: is discovered by dynamic routing protocols. Each entry in the FIB table contains the physical or logical interface through which a packet is sent to a network segment or host to reach the next router. An entry also indicates whether the packet can be sent to a destination host in a directly connected network.

Why are routes in the OSPF routing table on an S series switch in the inactive state
A policy that filters all OSPF routes may be configured in an OSPF process. As a result, all routes in the OSPF routing table are in the inactive state.

Why the number of routes in the OSPF routing table of the OSPF VPN multi-instance is less than the predicted number
In the OSPF VPN multi-instance, loops may occur if PEs and CEs learn BGP and OSPF routes from each other. You can set the DN in Type3, Type5, or Type7 LSAs advertised by PEs to 1 so that CEs ignore the LSAs with the DN value of 1. These LSAs are not used in route calculation, which prevents loops. If the preceding method is used to prevent loops, the number of routes in the OSPF routing table is less than the predicted number. To use the LSAs with DN 1 in route calculation, run the vpn-instance-capability simple command on CEs to disable routing loop detection.

Reasons for the fact that the number of default equivalent routes in the routing table is larger than the number of default static routes
The reasons for the fact that the number of default equivalent routes in the routing table is larger than the number of default static routes are as follows: Symptom: Two default equivalent routes are configured. [sysname] display current-configuration | in ip route ip route-static 0.0.0.0 0.0.0.0 GigabitEthernet1/0/11 42.x.y.1 ip route-static 0.0.0.0 0.0.0.0 GigabitEthernet1/0/10 110.x.y.1 ip route-static 10.0.0.0 255.0.0.0 Eth-Trunk0 10.x.y.249 ...... The routing table has three default equivalent routes. Check whether the following interface is configured with the gateway function: [sysname] display current-configuration interface ...... # interface GigabitEthernet1/0/0 alias Cernet ip address 210.43.47.174 255.255.255.252 service-manage http permit service-manage https permit service-manage ping permit service-manage ssh permit service-manage snmp permit service-manage telnet permit gateway 210.x.y.173 # ...... The gateway command is used to configure the gateway address of the smart routing member interface. By default, the gateway address of the smart routing member interface is invalid. If the interface is used as the smart routing member interface, you must configure the gateway address for it. The firewall delivers the routing entry but does not automatically generate the route configuration command (ip route-static).

Can public network routes be iterated to tunnels on S series switches
Q: Can public network routes be iterated to tunnels? A: For S series switches, by default, an unlabeled public network route can only be iterated to the outbound interface and next hop, but not a tunnel. If the route recursive-lookup tunnel command is executed, an unlabeled public network route can inherit the tunnel ID of an IGP or static route, allowing packets to be forwarded through MPLS routes. The route recursive-lookup tunnel command enables the switch to iterate unlabeled public network routes to tunnels. This command is valid only to unlabeled public network routes that require tunnel iteration. To control tunnel iteration more precisely, you can filter unlabeled public network routes by specifying an optional IP prefix list. The undo route recursive-lookup tunnel command disables tunnel iteration.

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