Can an OSPF neighbor relationship be established if the network types of the two S series switches are different

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Question: Can a Full neighbor relationship be established if the network types of the two ends of an OSPF link are different?

Answer: Yes. For example, two devices are interconnected through an Ethernet link. On one end of the link, the default broadcast network type is adopted. The other end is configured as OSPF peer-to-peer (P2P). Neighbor relationship can be established between these two devices, which reach the Full state by exchanging their Link State Databases (LSDBs). However, no route can be learned because OSPF devices need LSDBs to construct a Shortest Path Tree (SPT). The LSDBs, however, are problematic. That is, the link-state advertisements (LSAs) generated by one end consider the peer a broadcast neighbor, while the other end considers its peer a P2P neighbor. Therefore, no SPT can be constructed correctly and the Shortest Path First (SPF) algorithm cannot calculate the right routes either.

Other related questions:
Can an OSPF neighbor relationship be established between devices that are on different subnets
A neighbor relationship can be established between two routers that are not on the same subnet only when the devices are connected through point-to-point (P2P) links. On a Point-to-Multipoint (P2MP) network, you can determine whether adjacencies can be formed between neighbors that are not on the same subnet. In all other cases, the devices must be on the same subnet.

Must two S series switches be on the same network segment to set up an OSPF neighbor relationship
Question: Must the interfaces on two ends of an OSPF link be on the same network segment and the mask digits on the neighboring interfaces be consistent? Answer: When two S series switches are establishing an OSPF neighbor relationship, the interfaces on the broadcast network, NBMA network, or P2MP network must be on the same network segment and the mask digits on the neighboring interfaces must be consistent. The limitations do not apply to interfaces on a P2P network. On an OSPF P2P network, if the link-layer protocol is PPP, OSPF neighbors with IP addresses on different network segments can be in the Full state and correctly calculate routes. However, if the link-layer protocol is not PPP (for example, HDLC), devices with IP addresses on different network segments cannot establish an OSPF neighbor relationship. Through PPP negotiation, the local device can obtain the IP address of the remote device and have a route to the remote device without extra configuration.

Relationship among the media type, link type, and network type of OSPF on S series switches
Question: What are OSPF media type, link type, and network type? What is the relationship among them? Answer: OSPF media type, link type, and network type are described as follows: Media type: indicates types of physical links, including GigabitEthernet and Ethernet links. Link type (in LSAs): The link type in an LSA is set based on the ospf network-type setting, as defined in RFC 2328. On a point-to-point (P2P) network, the link type is point-to-point. If a device is connected to a transmission network, the link type is transit. If a device is connected to a stub network, the link type is stub. If a device is connected to a virtual link, the link type is virtual. Network type: The OSPF network type can be configured as required regardless of physical media. Currently, OSPF network types include P2P, broadcast, NBMA, and P2MP. Relationship among the media type, link type, and network type: The default OSPF network type depends on the media type, and the OSPF network type determines the link type in an LSA.

Can CE series switches use their secondary IP addresses to establish an OSPF neighbor relationship
CE series switches cannot use secondary IP addresses to establish an OSPF neighbor relationship.

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