Study on the target Switch

When another vswitch in the LAN is not attacked by a network virus, it is likely that the performance of the vswitch is relatively stable and the switch system cannot be remotely managed, I hope this article will teach you more things.

As one of the core devices in the LAN, the target switch's performance directly determines the network's data transmission performance. However, after a long period of work, the switch will inevitably encounter one or another fault. To solve the fault in time, the network administrator often uses a remote method to manage the switch system. However, sometimes we may encounter the failure to remotely manage the vswitch.

What measures should we take to address this fault? Now, this article analyzes the troubleshooting methods for such faults, hoping to help you! If the physical connection between the client system and the target switch device is not smooth, we certainly cannot remotely log on to the background management system of the target switch through the network channel to remotely manage it;

Therefore, when we are unable to remotely manage the target switch, we should first use the ping command to test the smooth status of the physical connection line. Of course, before testing the ping command, we must select a common client system that is in the same subnet as the target switch, then run the ping command to test whether the IP address of the switch device can be pinged normally.

If the ping fails, the physical connection status may be faulty. In this case, we can try to run the ping command again on another client system. Check whether the IP address of the target switch can be pinged normally. If the IP address of the target switch cannot be pinged, the problem may occur on the switch itself ".

For example, if the switching port is abnormal or the switch's Hardware performance is unstable, the ping failure may occur. Of course, if we can ping the IP address of the switch device from the normal client system, but cannot remotely manage the target switch device.

Most of the problems are caused by soft faults of the target switch. For example, the vswitch background management system has a low version, or the vswitch system has been infiltrated by network viruses. Sometimes, when a switching port is constantly impacted by large data capacity, the CPU resources of the Board on the corresponding port may be greatly consumed. In severe cases, all switching ports on the board may be suspended.

At this time, if we ping the IP address of the switch device through these dead switching ports, the failure will naturally fail, and the remote login operation will not succeed. To determine whether the switch port is working normally, we can use the console control line to directly connect to the switch control port and log on to the switch system's background management interface as a system administrator.

Execute the string command "display cpu" in the command line status of the interface to view the CPU resource consumption of each Board of the switch. If the CPU consumption rate of a Board is found to exceed 50%, therefore, a switch port on the corresponding Board may be constantly affected by large data volumes.

In order to find the target failover port, We can insert the network cable into each switch port of the Failover board in sequence, and then in the View Mode of the corresponding switch port, ping the gateway address of the LAN to see if the target gateway address can be pinged.

Once you find that a switch port cannot successfully ping the target gateway address, you must run the string command "display xxx" in view mode of the switch port ", "xxx" is the specified switch port. From the pop-up result interface, we can clearly determine the size of the input packet, output packet, and broadcast packet of the switching port.

If the size of the input and output data packets exceeds 1000 Mb/s at the same time, the data traffic on the current switching port is abnormal. In this case, to prevent the switch port from affecting the operation status of the entire switch, we must temporarily disable the enabling status of the target failover port by using the "shutdown" command in the switch system.

Then, we can further find the subnet status under the target failover port to find out the real "sin" that causes the switch board CPU to be excessively consumed, so as to restore the working status of the target switch port, in this way, we can remotely manage the target switch through the network.

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