Some details of Huawei OSPF

1、 Different types of LSA Medium link status ID The meaning of
type 1 Link state ID Is to declare that LSA Of routeID
type 2 Link state ID Is to declare that LSA The interface of IP
type 3 Link state ID Is the network segment that declares the route entry
type 4 Link state ID Is the route of the router that declares the external route ID
type 5 Link state ID Is the network number of the declared external route
type 7 Link state ID Is the network number of the declared external route

2、type3LSA Rules for passing
ABR You can only send the internal route of your own interface to area0
ABR The routes within the region and learned from other regions can be passed to non backbone routes

3、 Route summary
abr-summary 192.168.0.0 255.255.255.0 // stay ABR Sum up
asbr-summary 192.168.0.0 255.255.255.0 // stay ASBR Sum up

4、 Publish default route

default-route-advertise 10 type 2 [always] ： Publish default route , If you add always Indicates whether a default route exists or not, the default route will be published
Area view default-cost Modify the default cost 

5、 How to determine LSA New and old
Compare the serial numbers first , The bigger, the more priority
If the serial number is the same , Then compare the check value (checksum) The bigger, the more priority
If the check values are the same, compare LSA Of Age Whether time equals Max Age
If Age Time is not equal to Max Age Time , Will compare their differences , If the difference is greater than 900s Small first
If Age Time is not equal to Max Age Time , Will compare their differences , If the difference is less than 900s The explanation is the same LSA
（ among age Namely LSA The first item of Baotou ,maxage yes 3600s, If one LSA stay lsdb Medium age The value of the field exceeds 1800 It will be updated again , exceed 3600 It will be deleted ）

6、 Show lsdb Different types of LSA
display ospf lsdb 【router|network|summary|asbr|ase|nssa】
display ospf routing

7、 Conditions established by neighbors
The netmask is consistent
hello Consistent interval In the broadcast network hello The interval between packets is 10s
The neighbor failure time is the same

8、ospf network broadcast（ Interface view ）： Modify the link type of the interface
9、ospf dr-priority1 （ Interface view ）： Change the priority of the interface

10、 For routers , its P2P There are two types of links Link To describe , That is to say type1LSA Fill in two link information , One is the link type 1, Indicates a point-to-point link , The other is the link type 3, It means a terminal network , It uses a record form different from other links to indicate that it is a p2p link , Both of them link Record of information , This makes the link information fuller .

11、DR The election took place in 2-way After the phase , That is, two routers pass through each other hello Messages know each other's existence , Then the router goes through hello Routing in the message ID Go to the network segment DR and BDR The election of

12、 Virtual connection is not in progress DR and BDR The election of , Their link type is P2P

13、display ospf interface： It can display the network to which the interface is connected BR and BDR, That is, in a multipoint access network ospf Information about

14、ospf cost 100( Interface view )： Change the interface ospf cost value

15、stub  ： In an area ABR Up and in ospf The area view of , Turn the router into stub Area
16、stub no-summary ： In an area ABR Up and in ospf The area view of , Turn the router into totally stub Area
18、nssa  ： In an area ABR Up and in ospf The area view of , Turn the router into nssa Area
19、nssa no-summary ： In an area ABR Up and in ospf The area view of , Turn the router into totally nssa Area

20、ospf authentication
authentication-mode md5 1 cipher huawei123
authentication-mode simple cipher huawei123