1、 Hardware malfunction

1. power failure

   • reasonExternal power supply instability, aging power lines, lightning strikes, etc.
   • performanceThe power supply is damaged and the fan is stopped, causing the switch to malfunction. The POWER indicator light on the panel is off, indicating that the power supply is not working properly.
   • Troubleshooting and resolution：
     • Introduce independent power lines to provide stable power supply and add voltage regulators to avoid voltage fluctuations.
     • When conditions permit, use UPS (uninterruptible power supply) to ensure power supply and choose a model with voltage stabilization function.
     • Install professional lightning protection measures in the computer room to prevent equipment damage from lightning strikes.

2. Port malfunction

   • reasonImproper insertion and removal of fiber optic ports or twisted pair RJ-45 ports, physical damage, mismatched crystal head sizes, and exposure of twisted pair cables to lightning strikes outdoors.
   • performancePort contamination and physical damage result in communication interruption.
   • Troubleshooting and resolution：
     • Be careful when plugging and unplugging connectors to avoid live plugging and unplugging to reduce the failure rate.
     • After troubleshooting the computer connected to the port, determine if it is damaged by replacing the port.
     • After turning off the power, clean the contaminated port with an alcohol swab; If the port is damaged, it needs to be replaced.

3. Module malfunction

   • reasonImproper insertion and removal of stacking modules, management modules, expansion modules, etc., handling collisions, unstable power supply, etc.
   • performanceThe module is unable to function properly, affecting the overall functionality of the switch.
   • Troubleshooting and resolution：
     • Ensure that the switch and module power supply are functioning properly, and check if the module is plugged into the correct position.
     • Check if the cables connecting the modules are functioning properly. The management module needs to confirm the connection speed, parity check, and data flow control.
     • The expansion module needs to check whether the communication mode matches (such as full duplex or half duplex).
     • After confirming the module malfunction, immediately contact the supplier for replacement.

4. Backboard malfunction

   • reasonThe damp environment causes the circuit board to become short circuited due to moisture, and the components are damaged by high temperature and lightning strikes.
   • performanceThe internal modules of the switch are not functioning properly.
   • Troubleshooting and resolution：
     • If all internal modules cannot work under normal external power supply, it may be due to damage to the backplane.
     • Backboard failure requires replacement, usually handled by professional maintenance personnel.

5. Cable malfunction

   • reasonImproper connection of connectors, incorrect or non-standard cable production sequence, incorrect wiring connections, etc.
   • performanceThe switch system or port is not functioning properly.
   • Troubleshooting and resolution：
     • Check if the connectors are tightly connected and if the cable production is standardized.
     • Ensure that the cables are connected correctly and avoid using cross wires instead of straight wires, or interlocking optical fibers in the fiber optic cable.
     • Check if the wiring connection is causing a network loop.

2、 Software performance failure

1. System error

   • reasonThere are design flaws or vulnerabilities in the switch system software.
   • performanceSwitch full load, packet loss, incorrect packet, and other situations.
   • Troubleshooting and resolution：
     • The switch system provides methods such as web and FTP to download and update the system.
     • Develop the habit of frequently browsing device manufacturer websites and updating systems or patches in a timely manner.

2. Improper configuration

   • reasonBeginners may not be familiar with switches, or different switch configurations may lead to configuration errors.
   • performanceIncorrect VLAN partitioning leads to network disconnection, incorrect port closure, mismatched switch and network card mode configuration, etc.
   • Troubleshooting and resolution：
     • If there is no guarantee of configuration issues, first restore the factory default configuration and then gradually configure it.
     • Read the instruction manual before configuration to understand the detailed installation and user manual of the switch.
     • The English manual can be configured after consulting with the supplier's engineer.