1、 Environmental adaptability maintenance

1. temperature control
   • Working temperature rangeIndustrial switches typically support wide temperature operation from -40 ℃ to 75 ℃, but it is important to avoid prolonged exposure to extreme temperatures.
     • high temperature environment(such as boiler room, outdoor cabinet):
       • Install a cooling fan or air conditioner to ensure that the temperature inside the cabinet is ≤ 50 ℃.
       • Regularly clean the dust on the surface of the switch to prevent overheating caused by blocked heat dissipation holes.
     • low-temperature environment(such as cold storage, polar):
       • Choose a switch model with heating function or an external heating module to prevent condensation from freezing.
       • Preheat for 10-15 minutes before starting to avoid damage to the equipment due to excessive temperature differences.
   • temperature monitoringReal time monitoring through switch management interface or external temperature sensor, setting high temperature alarm threshold (such as 45 ℃).
2. Dust and moisture prevention
   • dustproof measures：
     • Installed in a closed cabinet, the cabinet door is equipped with a dust-proof net (aperture ≤ 0.5mm).
     • Clean the surface and heat dissipation holes of the switch with compressed air (pressure ≤ 0.3MPa) every quarter, avoiding the use of damp cloths.
   • Moisture proof treatment：
     • The relative humidity should be controlled between 10% and 90% (non condensing), and dehumidifiers should be equipped in humid environments such as coastal areas and underground pipe galleries.
     • When shutting down for a long time, seal the switch with a moisture-proof bag and place a desiccant (such as silicone) inside.
   • Prevention of condensate waterWhen the equipment is moved from a low-temperature environment to a high-temperature environment, it should be left to stand for 1 hour until the temperature is balanced before being powered on.
3. Anti electromagnetic interference
   • Shielding measures：
     • Use shielded twisted pair (STP) or fiber optic connections to avoid parallel wiring with power cables (spacing ≥ 30cm).
     • The grounding resistance of the switch housing is ≤ 4 Ω to prevent damage from static electricity or lightning strikes.
   • Anti interference testingRegularly check the network packet loss rate in strong electromagnetic field environments (such as near frequency converters and high-voltage lines). If the packet loss rate is greater than 0.1%, adjust the layout or install filters.

2、 Hardware reliability maintenance

1. Port and cable inspection
   • Port cleaning：
     • Clean the RJ45 port gold fingers with alcohol swabs every six months to prevent oxidation and poor contact.
     • Avoid frequent plugging and unplugging of cables. If replacement is necessary, use dust plugs to protect unused ports.
   • Cable fixation：
     • Secure the network cable with zip ties or cable trays to prevent loose or broken ports caused by vibration.
     • Fiber optic connectors need to be protected with dust caps, and the bending radius should be ≥ 10 times the cable diameter.
   • Port testingEvery month, use a network tester (such as Fluke) to check whether the port speed and duplex mode match, with an error rate of ≤ 10 ⁻⁹.
2. Power supply and cooling system
   • Power stability：
     • Use industrial grade UPS (uninterruptible power supply) for power supply, with a voltage fluctuation range of ≤± 10%.
     • The dual power module switch needs to be connected to power sources of different phases to achieve redundant backup.
   • Maintenance of cooling fan：
     • Clean the dust on the fan model every quarter and replace the aging bearings (when the noise increases or the speed decreases).
     • Fanless design switches need to ensure good ventilation in the cabinet to avoid heat accumulation.
   • Power redundancy testSimulate main power failure every six months and verify that the backup power switching time is ≤ 10ms.
3. Shell and structural inspection
   • Shell integrity：
     • Check for cracks or deformations in the switch housing, and whether the sealing strip has aged and fallen off (with a focus on dust and water resistance rating of IP40 or above).
     • Outdoor switches need to be coated with anti moisture, anti mold, and anti salt spray paint, and reapplied every 2 years.
   • install and fix：
     • When installing with guide rails, ensure that the snap fasteners are securely fastened to prevent equipment displacement caused by vibration.
     • Wall mounted installation requires the use of expansion bolts, with a load-bearing capacity of ≥ 3 times the weight of the equipment.

3、 Software stability maintenance

1. Firmware update
   • Pre-upgrade preparation：
     • Backup the current configuration file (via web interface or TFTP server).
     • Confirm that the new firmware version is compatible with existing hardware (such as optical modules, PoE functionality).
   • Upgrade operation：
     • Upgrade during non production hours to avoid network interruptions.
     • Use the provided upgrade tools (such as H3C Comware, Cisco IOS) to avoid compatibility issues caused by third-party tools.
   • Validate after upgradeCheck the port status, VLAN configuration, and routing table for normal operation. After running for 24 hours without any abnormalities, put it into production.
2. Configuration Management
   • access control：
     • Change the default username/password and enable SSH/HTTPS protocol instead of Telnet/HTTP.
     • Limit the management IP address range and disable unused services (such as SNPPv1, CDP).
   • configuration backup：
     • Automatically backup configurations to remote servers every week, with file names containing dates (such asswitch_config_20240301.cfg）.
     • The backup media is stored in a fireproof and moisture-proof cabinet, retaining the configuration files from the past 3 months.
   • Configure auditMonthly verification of configuration change records to prevent unauthorized modifications from causing network failures.
3. safety protection
   • Virus prevention：
     • Disable the USB interface of the switch to prevent virus transmission through USB drives.
     • Regularly scan switch firmware vulnerabilities (such as CVE vulnerability library) and promptly patch high-risk vulnerabilities.
   • Loop detection：
     • Enable STP/RSTP/MSTP protocol to prevent layer 2 loops and set port fast convergence time (such as Forward Delay ≤ 1 second).
     • Monitor the MAC address table and isolate ports and troubleshoot when abnormal MAC flooding is detected (such as adding over 100 new MAC addresses per second).
   • traffic monitoring：
     • Collect traffic data through SNMP or NetFlow and set threshold alarms (such as single port traffic>90% bandwidth for 5 minutes).
     • Perform traceability analysis on abnormal traffic (such as broadcast storms and ARP spoofing) and isolate problematic devices.