Shulou(Shulou.com)06/03 Report--

Today, I will bring you an experiment of troubleshooting:

Topology Diagram:

The original configuration is as follows: pc1

Pc2

Pc3

Pc4

SW1

SW2

SW3

SW4

R1

R2

The wrong train of thought: ~ 1. Check the terminal equipment ~ ~ check whether the IP address, subnet mask and gateway are configured correctly

From the above figure pc1, we can see that the pc1 does not configure the gateway; the pc2 acquires the IP address as DHCP, but the setting of the DHCP server is not mentioned in this topology; the pc3 configuration is correct; the pc4 gateway is written as 192.168.40.253, while the gateway address in the router is 192.168.40.254. The above is the configuration error, modified as follows

Pc1

Add the gateway 192.168.10.254.

Pc2

To change the acquisition method to static, enter the IP192.168.20.1 subnet mask 255.255.255.0 gateway 192.168.20.254

Pc3

The original configuration is correct and need not be modified.

Pc4

Change the gateway address from 192.168.40.253 to 192.168.40.254. Check layer 2 device ~ 1) vlan creation is configured correctly 2) Link mode is configured correctly

SW1:

Port gi0/0/1 has no de-tagged configuration; Port gi0/0/2 links are allowed to pass through vlan without vlan20

The modification is as follows: [SW1] int gi 0apher1 entry port [SW1-GigabitEthernet0/0/1] data from port hybrid untagged vlan40 to vlan40 is untagged [SW1-GigabitEthernet0/0/1] int gi 0Accord 2 entry port [SW1-GigabitEthernet0/0/2] port trunk allow-pass vlan all allows all vlan to pass through.

Sw2:

Port gi0/0/1 joins vlan20; port gi0/0/23 unconfigured link mode

The modification is as follows: [SW2] int gi 0port link-type trunk entry port [SW2-GigabitEthernet0/0/1] undo port default vlan delete the original configuration [SW2-GigabitEthernet0/0/1] port default vlan 10 re-delimit the port into int gi [SW2-GigabitEthernet0/0/1] int gi 0plink 23 entry port [SW2-GigabitEthernet0/0/23] port link-type trunk configuration link mode [SW2-GigabitEthernet0/0/23] port trunk allow-pass vlan all allows all vlan to pass through

SW3:

Port gi0/0/23 is not configured trunk link allows all vlan to pass, gi0/0/13 link mode is configured as access error

The modification is as follows: [SW3] int gi 0Accord 23 entry port [SW3-GigabitEthernet0/0/23] port trunk allow-pass vlan all allows all vlan to enter port [SW3-GigabitEthernet0/0/13] undo port link-type via [SW3-GigabitEthernet0/0/23] int gi 0Accord 13 entry port [SW3-GigabitEthernet0/0/13] undo port link-type deletes the original configuration link mode [SW3-GigabitEthernet0/0/13] port link-type trunk configuration link mode allows all vlan to pass through trunk [SW3-GigabitEthernet0/0/13] port trunk allow-pass vlan all

SW4:

Port gi0/0/1 is not configured to be de-tagged-the PC does not recognize vlan, and if you do not untagged, traffic can go up and down; gi0/0/2 link mode error, trunk link data are tagged, and this port is connected to a router, which the router does not recognize.

The modification is as follows: [SW4-GigabitEthernet0/0/2] undo port trunk allow-pass vlan30 deletes the original configuration and puts the port into Vlan30 [SW4-GigabitEthernet0/0/2] undo port link-type deletes the original link mode [SW4] int gi 0Taber 0 enter port [SW4-GigabitEthernet0/0/2] undo port hybrid untagged vlan30 deletes the original vlan30 tag [SW4-GigabitEthernet0/0/2] undo port hybrid pvid vlan deletes and adds PVID operation [SW4-GigabitEthernet0/] Undo port link-type deletes the original link mode configuration [SW4-GigabitEthernet0/0/2] port link-type access configures the link mode for access [SW4-GigabitEthernet0/0/2] port default vlan 30 to delimit the port into vlan~~3. Check layer 3 device ~ 1) check whether the gateway address is configured correctly 2) check the routing table to see if the route is configured correctly

R1

A. The vid configuration of the subinterface does not correspond to b, and the two subinterfaces do not enable the ARP broadcast function (if this command is not configured, the subinterface will not be able to actively send ARP broadcast messages, and the subinterface without vlan40 will not be able to receive the vlan40 message d. The ospf declaration type is P2P, which should be changed to broadcast e, ospf has not declared 192.168.10.0 and 192.168.20.0, and no neighbors have been established. Unable to implement the routing function is modified as follows: [R1] int gi 0Uniqqq2.1 entry port [R1-GigabitEthernet0/0/2.1] undo ip address delete the original ip address configuration Jan 24 2018 15:40:06-08:00 R1% IFNET/4/LINK_STATE (l) [0]: The line protocol IP on the interface GigabitEthernet0/0/2.1 has entered the DOWN state. [R1-GigabitEthernet0/0/2.1] int gi 0Accord 2.20 enters subport [R1-GigabitEthernet0/0/2.20] undo ip address deletes the original ip address configuration Jan 24 2018 15:41:20-08:00 R1% IFNET/4/LINK_STATE (l) [1]: The line protocol IP on the interface GigabitEthernet0/0/2.20 has entered the DOWN state. [R1-GigabitEthernet0/0/2.20] undo dot1q termination vid 10 delete encapsulation protocol operation [R1-GigabitEthernet0/0/2.20] dot1q termination vid 20 encapsulation protocol vlan20 [R1-GigabitEthernet0/0/2.20] ip address 192.168.20.254 255.255.255.0 configure gateway address Jan 24 2018 15:42:22-08:00 R1% IFNET/4/LINK_STATE (l) [2]: The line protocol IP on the interface GigabitEthernet0/0/2.20 has entered the UP state. [R1-GigabitEthernet0/0/2.20] arp broadcast enable turns on broadcast function [R1-GigabitEthernet0/0/2.20] int gi 0ram 0.10 enters subport [R1-GigabitEthernet0/0/2.10] dot1q termination vid 10 Encapsulation Protocol vlan10 [R1-GigabitEthernet0/0/2.10] ip address 192.168.10.254 255.255.255.0 configure gateway address Jan 24 2018 15:43:05-08:00 R1% IFNET/4/LINK_STATE ( L) [3]: The line protocol IP on the interface GigabitEthernet0/0/2.10 has entered the UP state. [R1-GigabitEthernet0/0/2.10] arp broadcast enable enables broadcasting function [R1-GigabitEthernet0/0/2.10] [R1] int gi 0Accord 2.40 enters subport [R1-GigabitEthernet0/0/2.40] dot1q termination vid 40 Encapsulation Protocol vlan40 [R1-GigabitEthernet0/0/2.40] ip address 192.168.40.253 255.255.255.0 configuration ip address Jan 24 2018 15:48:04-08:00 R1% IFNET/4/LINK_ STATE (l) [4]: The line protocol IP on the interface GigabitEthernet0/0/2.40 has entered the UP state. [R1-GigabitEthernet0/0/2.40] arp broadcast enable enable broadcast function [R1-GigabitEthernet0/0/2.40] Q exit [R1] int gi 0Tabash 0 entry port [R1-GigabitEthernet0/0/0] ospf entry process [R1-GigabitEthernet0/0/0] ospf network-type broadcast configuration ospf announcement party is broadcast [R1-GigabitEthernet0/0/0] Q exit [R1] ospf entry process [R1-ospf-1] area 0 entry area 0 configure [R1-ospf-1-area-0.0.0.0] network 192.168.10.0 0.0.0.255 declare Network range [R1-ospf-1-area-0.0.0.0] network 192.168.20.0 0.0.0.255 declare Network range [R1-ospf-1-area-0.0.0.0] network 192.168.40.0 0.0.0.255 declare Network range [R1- Ospf-1-area-0.0.0.0]

R2:

A, hello message key parameters are different from other routers, the default is 10, the other is 10, and R2 is 15, naturally can not establish neighbors, it is impossible to learn the routing entries of other routers, unable to achieve routing functions. B. Enable acl to make rules to allow and deny all traffic. This topology requires the interconnection of the whole network, and there is no need to restrict a certain traffic. C, ospf does not declare 192.168.30.0, does not establish a neighbor, cannot implement routing function e, ospf declares 192.168.12.0 0.0.0.0 wildcard error It should be 0.0.0.255 modified as follows: [R2] int gi 0 R2-ospf-1 0 enter port [R2-GigabitEthernet0/0/0] ospf timer hello 10 configure hello message sending time is default 10 [R2-GigabitEthernet0/0/0] Q exit [R2] undo acl name A30001 remove the limit 192.168.30.254 traffic [R2] ospf entry process [R2-ospf-1] area 0 enter area 0 configuration [R2-ospf-1-area -0.0.0.0] network 192.168.30.0 0.0.0.255 announces the network range [R2-ospf-1-area-0.0.0.0] network 192.168.12.0 0.0.0.255 announces the network range [R2-ospf-1-area-0.0.0.0] Q exit

Sw1:

OSPF [SW1] ospf entry process [SW1-ospf-1] area 0 entry area 0 configuration [SW1-ospf-1-area-0.0.0.0] network 192.168.40.0 0.0.0.255 announces network scope verification and testing pc1-pc2:

Pc1-pc3:

Pc1-pc4:

Attached:

Factors affecting OSPF neighbor establishment:

1. Make sure that the links in the minimum range are Ping-connected to each other; (switching)

R1:Ping R2

R2:Ping R1

2. Make sure the device port can send messages.

# network to declare the correct network scope

# make sure that the port that receives OSPF messages cannot be "passive port-silent-interface"

(the silent-interface of OSPF on Huawei equipment can neither be sent nor received.)

3. Ensure that the device port can receive messages

# network to declare the correct network scope

# make sure that ACL allows OSPF traffic

# make sure that the port that receives OSPF messages cannot be "passive port-silent-interface"

(the silent-interface of OSPF on Huawei equipment can neither be sent nor received.)

4. Make sure that the key parameters in the OSPF Hello package are consistent; [compare the parameters in hello]

& RID must not be the same for routers that directly establish a neighbor relationship.

& the region ID must be the same

& Certification must be successful

& the subnet mask must be the same (in special cases)

& hello time, must be the same

& dead time, must also be the same

& special tag bits, which must be exactly the same

& DR priority, cannot all be 0; (in special cases)

& 3-tier MTU, which must be exactly the same

Verify the command:

Display ospf peer brief / / View OSPF's neighbor table

Display ospf interface gi0/0/0 / / View the APIs of OSPF

So far, even if the fault is eliminated, in the process of troubleshooting, we must have our own ideas, where to check first, and then where to check, what the correct configuration is like, and how it is actually configured, and what is the difference? only in this way, can we correctly troubleshoot the fault, hoping to bring help to everyone, inadequacies, please give a lot of advice, thank you!

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