10-29-2024 09:24 PM
can i know what is the point of LS sequence when there's also LS age?
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10-29-2024 09:38 PM
How router detect Out of order of update with age?
It need seq to check out or order of update of ospf
MHM
10-29-2024 11:20 PM - edited 10-29-2024 11:33 PM
RFC 2328:
If the LS age field of one of the router's self-originated LSAs reaches the value LSRefreshTime [30 minutes], a new instance of the LSA is originated, even though the contents of the LSA (apart from the LSA header) will be the same.
(...)
Whenever a new instance of an LSA is originated, its LS sequence number is incremented, its LS age is set to 0, its LS checksum is calculated, and the LSA is added to the link state database and flooded out the appropriate interfaces.
(...)
When comparing an LSA to its previous instance, the following are all considered to be differences in contents:
(...)
Also see OSPF section in https://www.cisco.com/c/en/us/tech/ip/ip-routing/tsd-technology-support-troubleshooting-technotes-list.html
https://community.cisco.com/t5/switching/ospf-sequence-number-question/td-p/3220777
and search the CLN
Regards, ML
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10-29-2024 09:38 PM
How router detect Out of order of update with age?
It need seq to check out or order of update of ospf
MHM
10-30-2024 12:28 AM - edited 10-30-2024 12:30 AM
wait, im srry i dont read it carefully
10-30-2024 01:07 AM
so the TLDR would be like this?
10-30-2024 09:31 PM
Yes, if u need more details, there is good ospf info in the TCP/IP volume 1 book from Cisco press by J. Dolye.
Regards, ML
**Please Rate All Helpful Responses **
10-29-2024 11:20 PM - edited 10-29-2024 11:33 PM
RFC 2328:
If the LS age field of one of the router's self-originated LSAs reaches the value LSRefreshTime [30 minutes], a new instance of the LSA is originated, even though the contents of the LSA (apart from the LSA header) will be the same.
(...)
Whenever a new instance of an LSA is originated, its LS sequence number is incremented, its LS age is set to 0, its LS checksum is calculated, and the LSA is added to the link state database and flooded out the appropriate interfaces.
(...)
When comparing an LSA to its previous instance, the following are all considered to be differences in contents:
(...)
Also see OSPF section in https://www.cisco.com/c/en/us/tech/ip/ip-routing/tsd-technology-support-troubleshooting-technotes-list.html
https://community.cisco.com/t5/switching/ospf-sequence-number-question/td-p/3220777
and search the CLN
Regards, ML
**Please Rate All Helpful Responses **
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