Troubleshooting Optical Pass-Thru Module (OPM) issues

Resolving The Problem

1. To begin troubleshooting, check the following top issues. If your issue is listed, select the link, otherwise proceed to step 2.
   
   
   • SAN devices connected through OPM not seen in hardware (JS20)
   • Optical Pass-thru Module may not power up on insertion
   
   Pass-through modules enable daughter cards to access external switches without the need to place switches into the BladeCenter switch bays. The pass-through module takes electrical signals from daughter cards and passes them directly to a downstream switch module using copper wiring only. You can use the Optical Pass-Thru Module if you desire those signals to be converted to optical signals for external BladeCenter connections, or you can use the Copper Pass-Thru Module if you desire copper external connections.
   
   

   Description	Marketing part number	Replacement part number
   Optical pass-thru module (OPM)	02R9080	02R9082

   
   The OPM is a pass-thru module which enables the transmission and reception of network signals from different networking environments. The OPM does not read the network data it receives, instead the chipset in the OPM detects the network signal it receives from the processor blade and then directly connects that signal to the same network signal beyond the BladeCenter chassis. The ports on the OPM are fibre optic and an optical pass-thru cable with four SC or LC duplex optical connectors is needed in order to get the network signal out to its destination which could be a Myrinet switch, Fibre Channel switch or a Fibre Ethernet switch. The OPM provides optical connectivity to each blade server in a BladeCenter, without providing any internal switching capability. The channel that is created is "neutral" to the protocol, enabling the deployment of external switch devices with direct access to blade servers.
   
   
   • Inserts into any switch module bay
   • Provides connectivity to each blade bay
   • Provides an unswitched/unblocked network connection to each blade server
   • Includes four optical transceivers and two cables
     (Two standard cables enable blade bays 1 through eight, Two additional cables can be purchased to enable blade bays nine to 14)
     
     

   
   
   The BladeCenter Chassis previously could only have Fibre Channel or Ethernet expansion cards installed but not both at the same time. The Optical Pass-Thru Module changes this. Now, with the OPM, some processor blades can be using the fibre expansion cards, some can be using Myrinet expansion cards and some can be using either the integrated dual ethernet controllers on the processor blades or the 1 Gb ethernet expansion cards. The price of this greater flexibility is greater complexity. The key to success is to understand that each of the transceivers/ports on the OPM is dedicated to certain processor blade bays. If you have a processor blade in bay 4 of the BladeCenter chassis and it has a FC expansion card it will use the OPM transceiver 1 Port D. You can have a 1 Gb Ethernet expansion card on a processor blade in bay 3 and it would use transceiver 1 Port C. There would be no conflict.
   

2. Check the status and verify configuration of the OPM through the MM. The BladeCenter Management Module (MM) can be accessed by entering its IP address into a web browser. The web interface of the MM can then be used to monitor and view the status of the OPM.
   
   
   • Selecting Firmware VPD from the Monitors menu provides VPD information for the OPM such as: Firmware Type, Build ID, Filename, Date released and the Revision, Manufacturing ID, Hardware Revision, Part Number, FRU number.
     
     
   • The OPM can be managed via the MM web interface. This may be done by selecting Management from the I/O Module Tasks menu which opens the I/O Module Management screen. From the I/O Module Management screen the Advanced Management link for any OPM Module installed can be selected. Selecting the link opens the Advanced Management for I/O Module x screen. x being the number of the I/O module selected.
     
     
   • From the Advanced Management for I/O Module screen, POST results can be viewed. When the OPM POST's it will generate a code which will indicate if POST has successfully finished or has failed. The amber OPM error LED will be lit when POST is failed.
     • A POST code of FF means that POST was successful.
     • A POST code of 01 indicates an I2C timeout.
     • POST code 04 indicates an overtemp condition.
     • POST code 05 indicates a power failure.
     • If the POST code is not defined above follow normal escalation procedures for handling the problem.
       
       
   • The external ports on the OPM can be enabled or disabled from the Advanced Management for I/O Module screen.
     
     
3. Check the OPM LED indicators. The status information LEDs on the front of the OPM give its current status. You have a Power LED which if green indicates that the OPM has successfully passed POST. If the OPM does not pass POST then the amber Error LED will be lit. The sixteen Port Link LEDs indicate a whether or not there is a valid connection on that port channel. They also indicate whether or not both ends of the channel are communicating successfully and if they are using compatable network protocols. When any of the four amber Transceiver Error LEDs are lit it is an indication that there is a fault in one of the OPM transceivers. If the OPM fails POST one or more of these error LEDs may be lit. The OPM offers LED for troubleshooting connectivity:
   
   
   
   
   • The Power LED (green) will be on once POST has completed without any errors.
   • The Link LED (green) will be on when a valid link has been established to a given port.
     
     
4. Check OPM networking environment configuration. The OPM can be inserted into one of the switch module slots in the BladeCenter Chassis. Which switch module slot it is inserted into depends on the networking environment(s) it is too be used with.
   
   
   • Gigabit Ethernet networking environment

   To use the OPM in the 1 Gb Ethernet environment it can be inserted into any of the BladeCenter chassis switch module slots. If it is inserted into switch module slot 1 or 2 it will be used with the integrated dual Ethernet interfaces on the processor blades. If the OPM is installed in switch module slots 3 or 4 then the processor blades must have the 1 Gb Ethernet expansion card(s) installed.

   • Fibre channel networking environment

   To use the OPM with Fibre Channel it must be installed in switch module slot 3 or 4 and the fibre channel expansion card(s) must be installed.

   • Myrinet networking environment
     

   Myrinet is a high-speed/low latency cluster interconnect HPC (High Performance Computing) applications. To use the OPM with Myrinet network environment, it must be installed in switch module slot 4. This is because switch module slot 4 has been hardwired to the single port Myrinet expansion card. The Myrinet expansion card must be installed on the processor blade. The OPM will work in the other switch module slots but must be installed in switch module slot 4 to work with the Myrinet expansion card.

5. Check OPM transceiver configuration. Each transceiver and port on the OPM is dedicated to a processor blade bay. This is set and cannot be changed. The following table shows each transceiver/port and the processor blade bay they are dedicated:
   
   

   Blade Bay Number	Transceiver Number	Transceiver Port
   1	1	A
   2	1	B
   3	1	C
   4	1	D
   5	2	A
   6	2	B
   7	2	C
   8	2	D
   9	3	A
   10	3	B
   11	3	C
   12	3	D
   13	4	A
   14	4	B

   
   
   
   
   
   
6. Check OPM cabling to ensure it is firm and proper. The OPM has four external ports. Each port supports up to four of the blade servers in the BladeCenter as indicated in the picture. Port four of the OPM supports only two blade server bays and two cables are unused. From one to four optical pass-thru cables can be attached to the Optical Passthru Module. Optical couplers are supplied with the cables so that their length can be extended up to 150 meters. The Multi-Port Optical connector on the optical passthru cable is attached to the OPM fibre optic port and the other end of the cable, which has 4 SC or LC duplex optical connectors that are attached to networking device beyond the OPM. The 4 SC or LC duplex optical connectors are keyed to the processor blade bays via the ports on the OPM. The optical pass-thru cable does not come with the OPM and must be purchased as a separate item.
   
   
   
   The OPM fibre optic port 1 is keyed to processor blade bays 1, 2, 3 and 4 for example. The SC or LC duplex connectors on the other end of the Optical Pass-Thru cable are also keyed to match the processor blade bays. For example if you have a blade with a Fibre Channel expansion card installed in processor blade bay 2 you would attach the SC or LC duplex connector port B to your Fibre Channel switch. If you attached the SC duplex connector port A, C or D the FC Expansion card would not work. This will probably be the most common problem experienced. To minimize problems, the SC duplex connectors will labeled A, B, C and D. The following graphic shows how the connectors and cables are labeled as well as the processor blades they are keyed to. If and optical cable is attached to OPM fibre optic port 4 only ports A and Bare used. Ports C and D are not used. If a Fibre Channel expansion card is installed on a processor blade in processor blade bay 13 and the port C is attached to an external FC switch, the result will be that the FC expansion card will not work.
   
   
7. If Myrinet expansion cards are installed on the processor blades, the OPM must be installed in the BladeCenter switch module bay 4. If the OPM is in any other switch module bay the Myrinet expansion cards will not be able to communicate but other networking expansion cards will be able to work.
   
   
8. Make sure that the Optical Pass-Thru cable is attached to the correct transceiver port on the OPM and that the correct SC or LC duplex connector is attached to the external networking device. Remember each of the OPM transceivers are dedicated to certain processor blade slots. If you have a processor blade in slot 5 with an expansion card installed and you plug the Optical Pass-Thru cable into the OPM transceiver 1 the expansion card will not be able to communicate. This is because the OPM transceiver 1 is dedicated processor blade slots 1, 2, 3, and 4 not 5.
   
   
9. If a processor blade with an expansion card is installed in processor blade slots 13 or 14 the Optical Pass-Thru cable must be connected to OPM transceiver port 4. In this scenario only the A and B SC or LC duplex connectors can be used on the other end of the cable. This is because the OPM transceiver 4 is only dedicated to processor blade slots 13 and 14. The C and D duplex ports on the cable will not work in this scenario because there are no processor blade slots for them to connect to.
   
   
10. If Fibre Channel expansion cards are being used make sure that the OPM is installed in switch module bays 3 or 4.
    
    
11. For Ethernet the OPM can be installed in any of the 4 switch module bays. Remember though if it is installed in switch module bays 1 and 2 it will interface with the integrated Ethernet controllers. If it is installed in switch module bays 3 and 4 the Gb Ethernet expansion card must be installed.
    
    
12. Download and install the latest BladeCenter Management Module (MM) firmware updates and system support files:
    
    Note: Thermal shutdown issues were corrected with the latest OPM microcode. Please refer to the README file for additional information.
    
    
    • Download the latest OPM microcode
    • Download the latest BladeCenter support files
    
    To update the OPM microcode:
    
    Note: In order to update the firmware for the OPM the BladeCenter Management Module must be accessed via its web interface. Updating the firmware of the OPM could cause it to become unusable so it should only be done when there is a problem that the update will fix.
    
    
    1. use a web browser to access the Management Module by its IP address.
    2. Then under I/O Module Tasks select Firmware Updates.
    3. The next screen that appears is the Update I/O Module Firmware screen. On this screen select the target for the firmware update.
    4. Then click the browse button to locate the firmware update file. Once both the target and the correct firmware file have been chosen click the Update button.
    5. The OPM can be powered on and off via the Management Module's web interface. This should always be done after the firmware of the OPM has been updated. After the firmware has been updated it is very important to select Power/Restart from the I/O Module Tasks menu and power the OPM off and then back on again. Once the firmware has been updated the OPM must be powered off and then on again for the new code to be used. Until the OPM has been powered off and then on again, after a firmware update, it will continue to use the old code.
       
       
13. Check the available publications:
    
    
    • OPM Product Overview
    
    
14. If these steps have not solved your problem:
    Refer to your system's Hardware Maintenance Manual, or refer to "Need more help?"

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