Inthe XMR/MLX and MLX-e systems, system status is obtained periodically by the Management Module (MM) by polling other modules through a system-wide I2C bus.The I2C bus is a two-wire (Clock and Data) interface allowing the master device (in this case, the MM) to individually address multiple devices residing on the bus.In these systems, multiple I2C buses are routed on the backplane and used for communications between the MM and the line cards, SFMs, fan FRUs, and power supplies.Error monitoring in the application firmware is responsible for identifying problems in the I2C path, and setting alerts as necessary.
Beginning with Softwarerelease version 4.1, when an I2C failure occurs on a management module, a set of static and dynamic syslog messages are generated in the output of the
show logging command. A syslog message is also sent to the SNMP log server. A description of these messagesid described in the NetIron XMRHardware Installation Manual and the NetIron MLXHardware Installation Manual.