Run the display transceiver verbose command. In the command output, RX Power (dBM) displays the receive power of the optical module, and TX Power (dBM) displays its transmit power. Transceiver Type :1000_BASE_SX_SFP Connector Type :LC Wavelength(nm) :850This article describes why the Optical Tx/Rx Power fields may show 0 dBm in the CLI output of get system interface transceiver, even though the 40G QSFP+ interface is operational, traffic flows normally, and no hardware issues are present. This behavior is not a bug with the transceiver. Optical loss is measured in “dB” which is a relative measurement, while absolute optical power is measured in “dBm,” which is dB relative to 1mw optical power Loss is a negative number (like –3. These modules, including SFP, SFP+, and SFP28, are widely used in enterprise networks, data centers, and carrier-grade deployments. Generally, a high alarm or low alarm indicates that the optics module is not operating properly. When you plan to replace a configured optical module with a different type of optical module, you must clear the configurations of the old module before you install the new module.
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