I. Fault phenomenon

The network connection is abnormal. The gateway cannot be pinged.

II. Troubleshooting

1. Network setup problems:

（1）Check whether the network adapter driver is correctly installed and the network connection is normal;

（2）Ensure that the default gateway address is set correctly.

2. Network hardware failure:

（1）Check whether network cables, switches, routers and other hardware devices work properly;

（2）Try to replace the network cable or check the interface.

3. Firewall configuration problems:

（1）Check whether the firewall blocks ICMP (ping protocol);

（2）Ensure that the firewall rules do not block the ping command.

4. Network routing problems:

（1）Check whether the routing table is correctly configured to ensure that the path to the gateway is reachable;

（2）Try the traceroute command to see the path of the packet to the gateway.

5. Gateway device failure:

（1）Log in to the gateway device to check the device status and log information.

（2）Ensure that the gateway device works normally and the port is not occupied;

（3）Check that the configuration is correct.

6. Network congestion or packet loss:

（1）Check the network bandwidth usage to see if network congestion occurs;

（2）Run the ping -c command to check the packet loss rate.

7. Seek after-sales technical support:

service@glory-t.tech.

I. Fault symptoms：

The switch port is not configured with bpdu enable, which interrupts loop services.

• Networking Situation

As shown in the figure, STP is enabled globally on the Switch and multiple switches are connected to form multiple STP rings.

(Figure Networking diagram of service interruption caused by bpdu enable not configured on Switch ports)

• Symptom

When you log in to the Switch, a large number of broadcast packets are detected under the port, and a loop occurs in the network.

• Cause Analysis

According to the configuration analysis, STP is enabled globally on both switches, but bpdu enable is not configured on all connected ports.

#

interface GigabitEthernet0/0/4

port link-type access

port default vlan 10

loopback-detect enable

undo ntdp enable

undo ndp enable

#

For the two Switch devices with Layer 2 protocols such as STP and LACP enabled, you need to configure bpdu enable to send the received protocol packets to the CPU for processing. Otherwise, the protocol packets are discarded on the ports and protocol negotiation cannot be implemented.

II. Troubleshooting

If there is a loop in the network, check whether STP convergence is normal. When there is no blocking interface in the STP ring, you can run command to view the role of a specific port in the spanning tree and check whether the port can receive and send STP packets properly. For example:

Port Role :Designated Port // Port role

Port Priority :128 // Port priority

Port Cost(Dot1T) :Config=auto/Active=20000 // Port path cost

Designated Bridge/Port: 4096.5489-98f5-a433/128.34 // Specifies the bridge ID

BPDU Sent: 726

TCN: 0, Config: 0, RST: 0, MST: 726

BPDU Received: 0

TCN: 0, Config: 0, RST: 0, MST: 0

If all STP enabled interconnection ports have the Designated Port role, STP negotiation fails. Check whether bpdu enable is configured under the port. If not, you need to configure bpdu enable for the ports that participate in STP calculation.

III. Suggestions and Summary

The ports on the switch that participate in STP calculation must be configured with bpdu enable. Otherwise, the received STP packets are not processed (STP packet sending is not affected). bpdu enable is the default switch port.

When STP is enabled on the switch, other ports connected to terminals must be configured as edge ports. The port connected to the terminal can be automatically detected and the edge port property of the port is enabled.

1. First you need to eliminate connectivity issues. When the connectivity is normal, security zones are not added to the corresponding interfaces on the firewall, and service-manager ping and ssh permit are not added to the interfaces. This is because the firewall is affected by security policies that define security zones. Only after an interface is added to a security zone can the ping and ssh actions of the interface be allowed through the permit action executed in the security policy.

2. The service-manager ping and ssh permit commands on the interfaces are not affected by the security policies and directly execute the permit deny actions on the ping/ssh services corresponding to the interfaces. Each interface except the loopback and mgmt interfaces must be added to a corresponding security zone.

I. Fault phenomenon

Inter-floor interconnection through the optical port of the ODF optical switch, the port cannot be UP.

II. Troubleshooting

1. confirm whether the device port is enabled, if there is a VLAN confirm whether the port configuration is in the same VLAN;

2. Check whether the optical modules of the optical switches at both ends support the rate of the optical module. Some models of switches may not support 10-Gigabit modules.

3. check whether the optical fiber cable should be broken, light pen to check whether the optical transmission is complete;

4. check whether it exceeds the transmission distance supported by the module, cross-floor optical cable may lead to serious light failure need to replace the single-mode module and single-mode cable;

5. check whether the interface optical transceiver direction is reversed;

6. Test whether the ODF cable is connected with the luminous side.

I. Problem description

The link aggregation connection between the switch and the router fails.

II. Troubleshooting Procedure

1. Check the physical status of member ports and confirm that the ports are in Up state;

2. View LLDP neighbor information to obtain information about the peer；

3. View the working mode of link aggregation. The working mode of the local end and the peer end must be the same；

4. You can check whether the number of LACP packets is increased by checking whether LACP packets are received and sent；

5. Perform a single-link test, remove the link aggregation, and use the single-link direct connection test to check whether the connectivity is successful；

6. When the single-link test is used, it is found that neither of the two lines can ping through the other side, and the transmission device is not properly configured;

7. After the transmission device is checked, it is found that the transmission device works in simplex mode. After the transmission device works in full-duplex mode, the single-link communication is normal;

8. After the two links are aggregated again, the aggregation succeeds, the connectivity test is normal, and the fault is rectified.

III. Cause of the problem

Due to transmission equipment configuration problems, resulting in communication failure.

IV. Solution

It is recommended to test whether the single link test is successful and whether the rate is consistent before configuring the aggregation.

I. Problem description

The CPU usage of the device is high.

II. Solution

1. the cpu usage can be viewed on the device:

You can view the alarm overload threshold in the system view or on the NMS. By default, the alarm overload threshold of the CPU usage monitoring is 80%.

2. Check whether logs with high CPU usage are generated:

Based on the command output, you can obtain the tasks with high CPU usage and check whether the CPU usage needs to be adjusted.

3. If the cpu usage is high due to Layer 2 loops, the troubleshooting flowchart is as follows:

（1）Check the alarm. There may be an alarm indicating that the VRRP active/standby status is frequently switched；

（2） Check whether the active/standby status is normal；

（3）Check the statistics of VRRP packets sent to the CPU to see which interface board has a large number of packet losses；

（4）If the average bandwidth usage of the interface reaches more than 80%, there should be a loop；

（5）Manually shutdown the port whose usage exceeds the upper limit. Then check the statistics on VRRP packets sent to the CPU. The Drop statistics on VRRP packets does not increase. At the same time, you can Ping the management address of other access layer devices；

（6）Check the access layer device connected to the abnormal port and add the STP enable command.

I. Problem description

This topic describes the problem that the port of the optical module is down after the bandwidth is increased.

II. the fault symptom

The port does not get up.

III. Processing

(The handling process is a detailed record of the actual process. This field must have relevant information and cannot be left blank or filled with "none".)

1. View the port negotiation problem:

（1）You can see that the output and light are normal.

【Expansion】

If RX is outside the threshold or -40, the bare fiber transmission distance is too long, the receiving fiber is damaged, and the optical module temperature is too high or damaged.

If TX is outside the threshold or -40, the optical transceiver may be damaged, the port is shutdown, and the optical transceiver temperature is too high or damaged.

（2）You can see that the current negotiation is 1G, and the maximum can run 10G.

（3）The status says Link fault (220), which may be compatible with the optical fiber, optical module, and board.

2. Check whether there is a problem with the module and line:

After replacing the module and ring [single-core module can not ring] that the line is normal.

【 Expansion optical module】

The model of the peer end is different from that of the local end, as long as the parameters are consistent and supported by the device.

Ensure that the speed, center wavelength, transmission distance and other parameters of the optical module at both ends are consistent, but for the single-core module, it needs to be used in pairs, while the dual-core module does not.

3. negotiation mode, port rate change:

Change the port to the negotiation mode, the port rate is still not up.

4. Check whether the board supports 10G：

The board does not support the 10G module. Procedure

IV. Root causes of the problem

Because the board does not support the 10G module, the port cannot be lifted.

V. The solution

The port can be switched to adapt the 10G module board.

VI. Suggestions and summary

Before the change, it is necessary to consider that there may be faults involved, and try to avoid problems that are exposed during the change. When a problem is encountered, it is necessary to calmly troubleshoot it step by step.