The 1200 Watt Power Supply for AC Systems on the MGX platforms may exhibit an undetected fan failure when installed in a redundant power supply slot in the chassis. This is due to a defect with one of the two supply vendors for this part.
This malfunctioning redundant power supply will lead to unexpected system failure if the redundant supply is switched to due to primary power supply failure. A fully loaded system may not have sufficient power available at switchover due to an unreported failure of one or more of the redundant supplies.
Two suppliers have been used while shipping TAN 800-04746-02, Vendor 1 and Vendor 2. This failure exists only with the Vendor 1 power supply.
The Vendor 1 supply was shipped from 2000 to 2005 and is no longer used in the MGX product.
The primary Product ID is PS-1200-AC. All of the following PIDs use the same base part:
A redundant power supply unit has malfunctioned due to a fan failure that was not detected or reported by the system. No visual symptoms are shown.
If the system subsequently switches to redundant power supply due to a primary power supply failure, it may crash without warning if the redundant side has insufficient power available due to a unit failure.
How To Identify Hardware Levels
Methods to differentiate between Vendor 1 (affected) and Vendor 2 (unaffected) power supplies include:
1) If the power supply is located outside the chassis, use the manufacturer's label.
2) If the power supply is located inside the chassis check the following.
Fan - Vendor 1 (affected) units have a metal grill fan guard whereas the Vendor 2 (unaffected) units do not.
LED - Vendor 1 units have a protective black plastic protruding from the surface around the LED's labeled DC and AC whereas the Vendor 2 units do not.
3) The Vendor 1 power supply can be identified by a serial number that begins with "ABD".
Serial numbers may be obtained by looking at the manufacturer's label (see images above). Note that Vendor 2 does not show the serial number on the label. Alternatively, electronically check the serial number through SNMP using a Network Management System:
i) Customer starts their NMS (Network Mgmt Systems)
ii) Run SNMP Walk for OID (Object identifier) --- 22.214.171.124.126.96.36.199.1.1
iii) Look for Hardware devices - in this case power supplies (unit #1, 2, 3 .....).
iv) When power supplies have been identified note their corresponding index
v) Check entPhysicalSerialNum with the noted index. Corresponding
vi) See sample outputs (S/N)
entPhysicalSerialNum.17236106 = BNXXXXXXXXX (Vendor 2) ?------------Unaffected Supply
For More Information
If you require further assistance, or if you have any further questions regarding this field notice, please contact the Cisco Systems Technical Assistance Center (TAC) by one of the following methods:
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