预警标题

The Precaution about the Fixed Serial Port Damage of R and AR Series Routers

Precaution level

Critical

Product Type

R1760, R26 Serials, AR28 Serials

Versions

VRP1.74 release versions, VRP3.40 release versions

[Precaution Description]

As the thunderstorm season is coming, the fixed serial ports of R/AR series routers are damaged frequently.

[Reason]                                  

According to the analyses from R & D and supply chain, the reason is that the serial port chip is burned. Poor grounding protection measure or hot plugging in/out cables may cause serial ports damaged.

[Solution]

1.      Do not hot plug in/out serial cables at any time. It is necessary to plug in/out cables and replace equipments after power off in case of equipment installation and link and network failures troubleshooting.

2.      Grounding modifications are required for the sites which are not grounded well so as to prevent from mass serial port damage due to bad grounding.

Users must execute medications according to the grounding requirements in AR 28 Router (Fixed Serial Ports) Installation Specification.