How can an OSPF route be hidden so that it is not advertised to any other area

A filter list cannot solve this problem. You solve this problem through the following methods:

Configure route summarization on the Area Border Router (ABR), specifying the no-advertise keyword in the route summarization command.
Configure the filtering of OSPF ABR Type-3 LSAs. This feature extends the ABR capabilities so that an ABR can filter routes when advertising Type-3 LSAs between OSPF areas. This feature allows only packets with specified prefixes to be sent from one area to another area and restricts all packets with other prefixes. This type of area filtering can be applied out of a specific OSPF area, into a specific OSPF area, or into and out of the same OSPF areas at the same time.

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