Why does not an S series switch functioning as an ABR summarize addresses while advertising the routes

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Perform the following operations on the S series switch functioning as the ABR to solve the problem.
Run the display current configuration command to check whether all network segments in the area are consecutive.
If not, divide the network segments into several groups of consecutive network segments.
Run the abr-summary command on the ABR to summarize each group of consecutive network segments into one network segment.
Check the filter export command in the area view and ensure that the LSA for ABR route summarization is not filtered out.

Other related questions:
Why does an ABR advertise continuous network segment addresses of an area as a summary address
Perform the following steps to solve this problem: 1. Run the display current configuration command to check whether the network segment addresses of the area are continuous. 2. If the network segment addresses are discontinuous, divide them into several groups of continuous network segment addresses. 3. Run the abr-summary command to summarize each group of continuous networks into a single network on the area border router (ABR). 4. In area view, run the filter export command and ensure that the link-state advertisements (LSAs) summarized by the ABR are not filtered out.

On S series switches, why cannot inter-area OSPF route summarization take effect
Question: Why cannot inter-area OSPF route summarization take effect? Answer: As defined in RFC 2328, when an ABR summarizes inter-area routes, it directly generates a Type 3 LSA regardless of the configured range value. When the ABR summarizes intra-area routes, it generates a Type 3 LSA based on the configured range value. However, route summarization can cause more LSAs being transmitted into the backbone area, making the network unstable.

Definition of ABR in OSPF on S series switches
Question: What is the definition of ABR? Is a device with more than two areas configured an ABR? Answer: According to RFC 2328, an OSPF backbone area contains the ABRs of all areas. That is, an ABR must belong to a backbone area. If Area 2 and Area 3 are configured on a device with no interface in a backbone area, the device is not an ABR. If two or more areas are configured on an S series switch supporting OSPF and one of these areas is a backbone area, the switch is an ABR. Not all these areas must have interfaces in the Up state.

How does an S series switch hide an OSPF route so that the route is not advertised to any other area
Question: How to hide an OSPF route so that it is not advertised to any other area? Answer: A filter list on an S series switch supporting OSPF cannot prevent a route from being advertised. You can use either of the following methods: Configure route summarization on an ABR and specify the keyword no-advertise in the command. Configure an ABR to filter the routes carried in Type 3 LSAs. The ABR filters routes when advertising Type 3 LSAs between OSPF areas. Only the packets with prefixes meeting requirements can be transmitted from one area to another. In this way, the incoming and outgoing packets of an area are controlled.

Why does not an S series switch advertise IGP shortcuts and Forwarding Adjacency to the tunnel interface
Question: Why the IGP shortcuts and Forwarding Adjacency are not advertised to the tunnel interface? Answer: Perform the following operations on the S series switch to solve the problem. Ensure that the enable traffic-adjustment [ advertise ] command is configured. Ensure that OSPF supports tunnel traffic adjustment. Ensure that the metric type and metric value are configured on the tunnel as required. Ensure that the MPLS TE is correctly configured on the tunnel interface.

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