After the shutdown command is executed on an interface of an S series switch, an LSA sent by the switch still exists in the peer LSDB. Why

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Question: Two devices are connected using a link. After the shutdown command is executed on an interface on one end of the link, an LSA sent by the interface still exists in the peer LSDB. Why?
Answer: An LSA can be flooded only by the S series switch supporting OSPF that generates the LSA. When the peer switch has no reachable path to the local switch, new LSAs generated by the local switch will not be flooded to the peer. Therefore, the old LSA exists in the peer LSDB. It is not used in SPF calculation and ages with time.

Other related questions:
For S series switches, why is the BGP connection not immediately closed after the shutdown command is executed on the interfaces connecting two peers
Q: Why is the BGP connection not cut off immediately after the shutdown command is executed on interfaces connecting two devices? A: When the EBGP peers are directly connected and the ebgp-interface-sensitive command is executed in the BGP view, the BGP peer connection is interrupted immediately after the interfaces connecting the two peers are shut down. By default, the ebgp-interface-sensitive command is executed in the BGP view. In other cases, the BGP peer relationship is not interrupted until the Hold timer times out.

Why are BGP connections reestablished after the peer connect-interface command is executed on S series switches
Currently, S series switches do not support BGP dynamic capability negotiation. Therefore, when capabilities of the BGP neighbor are changed, the BGP connection is automatically cut off and then the capabilities of the neighbor are renegotiated. If the peer connect-interface command is configured, the BGP session needs to be set up by designating the egress. Therefore, the source address of the TCP connection may be changed and the TCP connection needs to be re-established by using the new source address.

Why an S series switch cannot be registered after the reboot member command is executed
When the reboot member command is executed on an S series switch (excluding the S1700), the specified member switch restarts. The configuration file specified for the current startup is deleted on the member switch; therefore, the configuration file is lost and the member switch cannot be registered. Exercise caution when you use the reboot member command. V100R006C05, V200R002, and later versions do not support HGMP.

Why cannot an OSPF route contained in the LSDB/LSA be queried in the routing table on an S series switch
Question: Why cannot an OSPF route contained in the LSDB/LSA be queried in the routing table? Answer: Perform the following operations on the S series switch to solve the problem. Check whether the IP address is valid. Check whether the forwarding address is known and reachable. Check whether the route aggregation or route import is correct. Check whether a different mask or IP address is used in P2P connection. Check whether the advertise route list is configured. Check whether the connection with the backbone area is proper. Check whether OSPF is enabled on the secondary IP address instead of the primary IP address.

How to clear the recycle bin of an S series switch
For S series switches (except S1700 switches), run the following command to clear the recycle bin:
<HUAWEI> reset recycle-bin
Note: The delete XXX command in the user view only moves files to the recycle bin, but does not release the storage space. You can run the dir/all command to view information about all files, including deleted files in the recycle bin marked in brackets ([ ]). These files can be restored using the undelete command. To permanently delete these files from the recycle bin, run the reset recycle-bin command. The files that are deleted using the delete command without the /unreserved parameter are saved in the recycle bin.

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