System
Cisco MDS 9000 Series Multilayer Switches. Specifically seen in MDS 9148
Software Versions
Currently known influential versions are 8.1(1) and 8.2(1)
Issue
MDS9148S shows intermittent ChassisFan failures and absurdly high SFP temperature alarms.
The following logs combination is found in show logging log (SFP temperature and ChassisFan can vary):
Description
2019 Apr 11 11:05:41 SW1-UP %USER-3-SYSTEM_MSG: lc_port_cfg: (line 609):SFP in port '1' reported temperature alarm. SFP temperature = '1274 C', threshold '78 C' - lc_port_cfg
2019 Apr 11 11:05:41 SW1-UP %USER-3-SYSTEM_MSG: lc_port_cfg: (line 609):SFP in port '2' reported temperature alarm. SFP temperature = '1275 C', threshold '78 C' - lc_port_cfg
2019 Apr 11 11:05:41 SW1-UP %USER-3-SYSTEM_MSG: lc_port_cfg: (line 609):SFP in port '3' reported temperature alarm. SFP temperature = '1274 C', threshold '78 C' - lc_port_cfg
2019 Apr 11 11:05:41 SW1-UP %USER-3-SYSTEM_MSG: lc_port_cfg: (line 609):SFP in port '7' reported temperature alarm. SFP temperature = '1275 C', threshold '78 C' - lc_port_cfg
2019 Apr 11 11:05:41 SW1-UP %USER-3-SYSTEM_MSG: lc_port_cfg: (line 609):SFP in port '8' reported temperature alarm. SFP temperature = '1275 C', threshold '78 C' - lc_port_cfg
2019 Apr 11 11:05:41 SW1-UP %USER-3-SYSTEM_MSG: lc_port_cfg: (line 609):SFP in port '9' reported temperature alarm. SFP temperature = '1275 C', threshold '78 C' - lc_port_cfg
Important Note: This is not harmful to the system, transceivers, or fans. These are false alarms that are displayed and by viewing the DOM details you can still see the true temperature values:
SFP Diagnostics Information:
----------------------------------------------------------------------------
Alarms Warnings
High Low High Low
----------------------------------------------------------------------------
Temperature 34.01 C 90.00 C -10.00 C 85.00 C -5.00 C
Voltage 3.31 V 3.63 V 2.97 V 3.46 V 3.13 V
Current 7.24 mA 15.00 mA 1.00 mA 12.00 mA 2.00 mA
Tx Power -2.27 dBm 0.79 dBm -7.97 dBm 0.00 dBm -7.00 dBm
Rx Power -2.99 dBm 3.01 dBm -16.02 dBm 0.00 dBm -13.00 dBm
Transmit Fault Count = 0
----------------------------------------------------------------------------
Note: ++ high-alarm; + high-warning; -- low-alarm; - low-warning
Solution
Reloading the switch has been reported to temporarily resolve this issue.
Recommend updating the software version to another stable build
Sources
https://quickview.cloudapps.cisco.com/quickview/bug/CSCvn66653