LightStream 2020 switches are designed to have a low mean time to repair (MTTR). FRUs are easily accessible and easy to replace. You should be able to complete each of the procedures detailed here within 15 minutes, except where otherwise noted.
Most of the procedures in this chapter can be completed by one person. The exception is the disk assembly connector replacement, which should be done by two people.
The LightStream 2020 allows power-on servicing, which means that most portions of the system can be serviced while the unit continues to operate. You can perform power-on servicing on the following FRUs:
Note Replacing the bulk power tray in a nonredundant system causes the system to power down. Replacing an NP in a nonredundant system interrupts the flow of traffic. Replacing a switch card in a nonredundant system effectively shuts down the system.
Before replacing the following FRUs, you must perform an orderly shutdown of the LightStream 2020 system and turn off power:
- Midplane
- Disk assembly connectors
Refer to the section "Performing an Orderly Shutdown" for instructions on performing an orderly shutdown of a LightStream 2020 switch.
If you discover a problem in a component that is not itself an FRU, you must replace the FRU of which the component is part. For example, if you find a fault in a hard disk drive, replace the entire disk assembly.
Figure 3-1 and Figure 3-2 show the locations of FRUs from the front and rear of the chassis.
Returning Failed FRUs
When you remove a faulty component from a LightStream 2020 system, you can return it for repair. Here's what to do:
Step 1 Contact the Cisco Systems Customer Response Center (CRC) to obtain a return material authorization (RMA) number and an address to which to ship the FRU. Here's how to reach the CRC:
- by phone: 1-800-553-2447 or (408) 526-8209
by fax: (408) 526-8787
by email: tac@cisco.com
- Give the CRC the following information:
- System assembly serial number and description
- Maintenance contract number, if applicable (a contract number is not required if you are purchasing service on an as-needed basis)
- Software version and hardware configuration
Step 2 Attach a tag to the FRU that lists the RMA number and describes the problem you experienced. Include instructions on how to reproduce the problem and a list of the diagnostic test numbers that the FRU failed.
Step 3 Pack the FRU securely and ship as directed.
Step 4 Record the replacement in your system's maintenance log.
Required Tools and Equipment
The following is a complete list of tools and equipment you must have on hand when replacing FRUs:
- A 5/16-inch slot-tip screwdriver
- A Phillips screwdriver (#1 for replacing a disk assembly connector; #2 for replacing the midplane)
- Temporary labels for any cables that will be disconnected during the procedure (Labelling cables enables you to reconnect them correctly at the end of the procedure.)
- Permanent labels for any fantails that will be replaced during the procedure
- Access to a console for deactivating and powering down FRUs
- A copy of the LightStream 2020 Network Operations Guide or access to the on-line documentation on UniverCD
- A grounding wrist strap for ESD protection
- Antistatic mats or shielding bags to protect any FRUs being removed from the chassis
Figure 3-1 : Front view of a LightStream 2020 switch showing FRUs.
Figure 3-2 : Rear view of a LightStream 2020 switch showing FRUs.
Replacing a Switch Card
This section explains how to remove and replace a switch card. If the system is passing traffic, note the following:
- In a redundant system, you should not replace the active switch card; refer to the LightStream 2020 Network Operations Guide for the procedure to force active and backup cards to exchange roles.
- In a nonredundant system, note that replacing the switch card causes the system to halt.
Removal
Step 1 Before you attempt to remove the card from the chassis, refer to the LightStream 2020 Network Operations Guide and follow the procedures to deactivate the line card and turn off power in the card slot.
Step 2 Unscrew the captive screws at the top and bottom of the card.
Step 3 Using the extractor handles, pull the card out of its slot. (See Figure 3-3.)
Warning 48-volt potential is present on the midplane at high levels. Be very careful when accessing this area; don't touch the midplane unnecessarily, and avoid contact with connectors and alignment pins.
Replacement
Step 1 Insert the new switch card into the slot, taking care to seat the card firmly in the midplane.
Step 2 Lock down the extractor handles and tighten the screws that hold the card in place.
Step 3 Refer to the LightStream 2020 Network Operations Guide for instructions on powering up and reactivating the slot.
Note When you complete this procedure, check the front and back of the system to see that all boards, disks, blowers, bulkheads, filler panels, and covers are in place and firmly screwed to the chassis frame. When all these items are in place, they form an enclosure that prevents the escape of electro-magnetic interference and maintains air flow through the chassis.
Figure 3-3 : Switch card replacement.
Replacing a Network Processor card
This section explains how to remove and replace an NP card. If the system is passing traffic, note the following:
- In a redundant system, you should not replace the active NP; refer to the LightStream 2020 Network Operations Guide for the procedure to force active and backup cards to exchange roles.
- In a nonredundant system, note that replacing the NP may interrupt the flow of traffic.
Removal
Step 1 Before you attempt to remove the card from the chassis, refer to the LightStream 2020 Network Operations Guide and follow the procedures to deactivate the card and turn off power in the card slot.
Step 2 Unscrew the retaining screws at the top and bottom of the card.
Step 3 Using the extractor handles, pull the card out of its slot. (See Figure 3-4.)
Replacement
Step 1 Insert the new NP card into the slot, taking care to seat the card firmly in the midplane.
Step 2 Lock down the extractor handles and tighten the screws that hold the card in place.
Step 3 Refer to the LightStream 2020 Network Operations Guide for instructions on powering up and reactivating the slot.
Note When you complete this procedure, check the front and back of the system to see that all boards, disks, blowers, bulkheads, filler panels, and covers are in place and firmly screwed to the chassis frame. When all these items are in place, they form an enclosure that prevents the escape of electro-magnetic interference and maintains air flow through the chassis.
Figure 3-4 : NP card replacement.
Replacing a Line Card
This section explains how to remove and replace a line card.
Caution Do not swap one line card for another unless you're sure that the cards are of the same type. Most line cards can be configured as either edge or trunk cards. You can't determine by looking at a card whether it's an edge or a trunk; check the configuration or use the show card command in CLI.
Removal
Step 1 Before you attempt to remove the line card from the chassis, refer to the LightStream 2020 Network Operations Guide and follow the procedures to deactivate the line card and turn off power in the card slot.
Step 2 Unscrew the retaining screws at the top and bottom of the card.
Step 3 Using the extractor handles, pull the card out of its slot. (See Figure 3-5.)
Replacement
Step 1 Insert the new line card into the slot, taking care to seat the card firmly in the midplane.
Step 2 Lock down the extractor handles and tighten the screws that hold the card in place.
Step 3 Refer to the LightStream 2020 Network Operations Guide for instructions on powering up and reactivating the slot.
Note When you complete this procedure, check the front and back of the system to see that all boards, disks, blowers, bulkheads, filler panels, and covers are in place and firmly screwed to the chassis frame. When all these items are in place, they form an enclosure that prevents the escape of electro-magnetic interference and maintains air flow through the chassis.
Figure 3-5 : Line card replacement.
Replacing an Access card
This section explains how to remove and replace an access card.
Removal
Step 1 Before you attempt to remove the access card from the chassis, refer to LightStream 2020 Network Operations Guide and follow the procedures to deactivate the card and turn off power in the card slot. (Note that in order to deactivate and power down the access card you intend to replace, you must deactivate and power down the NP or line card associated with the access card. When you deactivate or power down a line card or NP, the same thing happens to the associated access card.)
Step 2 Disconnect any cables attached to the access card. Label them so that you will be able to reconnect them to the new access card in exactly the same configuration.
Step 3 Unscrew the retaining screws at the top and bottom of the card.
Step 4 Using the extractor handles, pull the card out of its slot. (See Figure 3-6.)
Replacement
Caution Before installing the new access card, ensure that the function card in that slot is turned off. (Check the VCC (power) LED on the card.) Connecting an access card to a powered-on function card can damage the access card.
Step 1 Insert the new access card into the slot, taking care to seat the card firmly in the midplane.
Step 2 Lock down the extractor handles and tighten the screws that hold the card in place.
Step 3 Reconnect any cables that you disconnected when you removed the old access card.
Step 4 Refer to the LightStream 2020 Network Operations Guide for instructions on powering up and reactivating the slot.
Note When you complete this procedure, check the front and back of the system to see that all boards, disks, blowers, bulkheads, filler panels, and covers are in place and firmly screwed to the chassis frame. When all these items are in place, they form an enclosure that prevents the escape of electro-magnetic interference and maintains air flow through the chassis.
Figure 3-6 : Access card replacement.
Replacing a Power Tray
This section explains how to remove and replace a bulk power tray. Power trays are accessible from the rear of the chassis.
There are two types of AC power tray:
- The Release 2.1 AC power tray has a handle, a power inlet and a circuit breaker switch on its attached front panel
- The Release 1 AC power tray has a separate, blank cover.
In addition, there is a DC power tray for DC-powered systems. This section gives separate removal procedures for each type of power tray, followed by a single replacement procedure for all three tray types.
Removing Release 2.1 AC Power Trays
Step 1 If this system has two power trays, skip to Step 2. If it has only one and is still operating, shut the system down before proceeding. (If you remove the only power tray in a system that is operating, the system loses power and ceases to operate.) See the section "Performing an Orderly Shutdown" for instructions.
Step 2 On the power tray you intend to replace, flip the circuit breaker to OFF and disconnect the power cord. (See Figure 3-7.)
Step 3 Unscrew the two captive screws that hold the power tray in place.
Warning When you remove the power tray, lethal AC voltage levels as well as 48 VDC are exposed. Touch only the front panel and the handle of the power tray. Do not insert tools or hands into the power supply tray or into the chassis.
Step 4 Slowly slide the power tray out of the chassis.
Removing Release 1 AC Power Trays
Step 1 If this system has two power trays, skip to Step 2. If it has only one and is still operating, shut the system down before proceeding. (If you remove the only power tray in a system that is operating, the system loses power and ceases to operate.) See the section "Performing an Orderly Shutdown" for instructions.
Step 2 Unscrew the two captive screws that hold the power tray's cover in place. Remove the cover.
Warning When you remove the power tray cover, lethal AC voltage levels as well as 48 VDC are exposed. Touch only the front lip and the sides of the power tray. Do not insert tools or hands into the power supply tray or into the chassis.
Step 3 Unscrew the two captive retaining screws that hold the power tray assembly in place. (See Figure 3-7.)
Step 4 Slowly slide the power tray out of the chassis.
Removing DC Power Trays
Note Removal and replacement of DC power trays should be performed by a qualified service person or a licensed electrician.
Step 1 Shut the system down and turn off the power. See the section "Performing an Orderly Shutdown" for instructions.
Step 2 Disconnect the power wires and the alarm wires (if any) from the front of the power tray.
Step 3 Unscrew the two captive retaining screws that hold the power tray assembly in place. (See Figure 3-7.)
Step 4 Slowly slide the power tray out of the chassis.
Figure 3-7 : Replacing power trays.
Replacing Power Trays (AC or DC)
Step 1 Slide the new power tray into the housing in the chassis. Make sure that the power tray fits snugly.
Step 2 Tighten the two screws that hold the power tray assembly in place.
Step 3 Do one of the following:
- If you're installing a Release 2.1 AC power tray with a circuit breaker and power inlet, reconnect the power cord.
- If you're installing a Release 1 AC power tray, replace the cover. Secure the cover with the two captive screws that hold it in place.
- If you're installing a DC power tray, reconnect the power wires and the alarm wires (if any) to the terminals on the front of the power tray.
Step 4 Turn on the power.
Step 5 Check the green LED on the power tray to ensure that the power is on. (On power trays with circuit breaker switches, the LED is just below the switch. On other trays, you should be able to see the LED through the cover.)
Note When you complete this procedure, check the front and back of the system to see that all boards, disks, blowers, bulkheads, filler panels, and covers are in place and firmly screwed to the chassis frame. When all these items are in place, they form an enclosure that prevents the escape of electro-magnetic interference and maintains air flow through the chassis.
Replacing a Blower
This section explains how to remove and replace a blower.
The blowers are at the top of the LightStream 2020 chassis. One is accessible from the front and the other is accessible from the rear.
Removal
Step 1 Unscrew the two captive screws that hold the blower cover in place. Remove the cover.
Step 2 Unscrew the retaining screws (bottom front of the blower, shown in Figure 3-8) and slowly slide the blower out until its power LED goes out. When the impeller inside the blower stops spinning, remove the blower completely from the chassis.
Warning The impeller inside the blower box may still be turning when you loosen the retaining screws. Keep fingers, screwdrivers and other objects away from the openings in the blower's housing. Do not remove the blower from the chassis until the impeller stops moving.
Replacement
Step 1 Slide the new blower into the chassis. Tighten the retaining screws (bottom front).
Step 2 Check the power LED on the front of the blower. It should be on if the system is powered up. (If the LED does not light up, the system may have a connector problem or a power problem.)
Step 3 Replace the cover and tighten the two screws that hold it in place.
Note When you complete this procedure, check the front and back of the system to see that all boards, disks, blowers, bulkheads, filler panels, and covers are in place and firmly screwed to the chassis frame. When all these items are in place, they form an enclosure that prevents the escape of electro-magnetic interference and maintains air flow through the chassis.
Figure 3-8 : Blower replacement.
Replacing a Disk Assembly
This section explains how to remove and replace a disk assembly.
The disk assembly is a single FRU consisting of a hard disk drive, a floppy disk drive and an associated power supply. A LightStream 2020 switch can have up to two disk assemblies. Each disk assembly is associated with a network processor card, and is connected to the network processor card by a ribbon cable attached to a male connector at the rear of the disk assembly slot.
Note There are two versions of the disk assembly: one for AC-powered systems, the other for DC-powered systems.
Removal
Step 1 Unscrew the two screws that hold the disk assembly in place (Figure 3-9).
Step 2 Slowly slide the disk assembly out of the enclosure.
Warning When you remove the disk assembly, live power circuits are exposed. Touch only the handle on the front of the disk assembly until you can remove it from the chassis. Do not insert tools or hands into the disk assembly or into the chassis.
Replacement
Step 1 Slide the new disk assembly into the enclosure. When the connectors begin to engage, push slowly and gently to avoid damaging the pins.
Step 2 Tighten the two screws that hold the disk assembly in place.
Note Check the front and back of the system to see that all boards, disks, blowers, bulkheads, filler panels, and covers are in place and firmly screwed to the chassis frame. When all these items are in place, they form an enclosure that prevents the escape of electro-magnetic interference and maintains air flow through the chassis.
Step 3 If you are running the release of LightStream 2020 software that is installed on the disk drive you just installed, your replacement is complete; you can stop now. (The disk assembly is shipped with the most recently released software installed on it.) If you are not running the software that came on the disk, you must install the software you are running. See the LightStream 2020 Network Operations Guide for instructions on installing software on the replacement disk.
Figure 3-9 : Disk assembly replacement.
Replacing a Disk Assembly Connector
This section tells you how to replace the 64-pin male DIN connector that is present at the back of each disk assembly slot in Release 2.0 and earlier hardware. Replace this connector if you notice that any of the pins are bent or broken.
Have a second person on hand to help you with this procedure. The disk assembly connector is a two-piece "press fit" connector, shown in Figure 3-10. One piece inserts from the rear of the chassis and the other inserts from the front, making it difficult for one person to install a new connector alone.
Figure 3-10 : Front and back sections of disk assembly connector shown with ribbon cable.
Removal
Step 1 Perform an orderly shutdown of the system, as described in the section "Performing an Orderly Shutdown".
Step 2 Remove the bulk power tray behind the connector that is being replaced. (See the section "Replacing a Power Tray" if you need instructions on removing the power tray.)
Step 3 Following the instructions in the section "Replacing a Disk Assembly," remove the disk assembly from the enclosure.
Step 4 From the rear of the chassis, unscrew the two Phillips-head screws that hold the SCSI ribbon cable in place at the rear of the disk assembly connector. Remove the ribbon cable. (Figure 3-10 shows how these pieces fit together.)
Step 5 Remove the two 3/16 lug screws from the rear of the connector. (These lugs held the screws removed in the previous step.)
Step 6 From the front of the chassis, remove the two Phillips-head screws from the front of the connector.
Step 7 Make a note of how the connector is keyed so that you can install the new one in the same manner.
Step 8 Disassemble the connector and remove it.
Replacement
Step 1 The new connector consists of a back piece with pins and a front piece with holes. Have the person who is helping you hold the front piece in front of the hole in the sheet metal where the connector is being installed, as shown in Figure 3-11.
Step 2 From the rear of the chassis, insert the pins on the back of the connector through the hole in the sheet metal and through the front piece of the connector (which is held in place by the person helping you). When the two pieces of the connector begin to engage, push slowly and gently to avoid damaging the pins.
Step 3 Have your helper replace the two Phillips-head screws in the front of the connector.
Step 4 While your helper holds the two Phillips-head screws in place from the front, replace the two 3/16 lug screws in the rear of the connector.
Figure 3-11 : Front and back pieces of disk assembly connector mate through a hole in the bulkhead at the back of the disk assembly slot.
Step 5 Replace the SCSI ribbon cable at the rear of the connector and secure it with the two Phillips-head screws that hold it in place.
Step 6 Carefully slide the disk assembly back into the enclosure. When the connectors begin to engage, push slowly and gently to avoid damaging the pins. Tighten the retaining screws that hold the disk assembly in place.
Step 7 Replace the power tray behind the connector that was replaced.
Step 8 Turn on the power and bring the system back up.
Note When you complete this procedure, check the front and back of the system to see that all boards, disks, blowers, bulkheads, filler panels, and covers are in place and firmly screwed to the chassis frame. When all these items are in place, they form an enclosure that prevents the escape of electro-magnetic interference and maintains air flow through the chassis.
Replacing the Midplane
This section explains how to remove and replace the midplane. The first procedure tells you how to learn the chassis ID, which is stored in EEPROM on the midplane. You must find and record this number before removing the old midplane so you can store it in the EEPROM on the new midplane. (The EEPROMs are located on the back of the midplane near the middle of the top edge; the positions are labelled u1 and u2.)
Estimated time to complete these procedures: two hours
Finding the Chassis ID
The chassis ID should be recorded in each node's maintenance log. If the chassis ID isn't in the log, you can use this procedure to learn it, provided the EEPROMs on the midplane are healthy.
Step 1 Log into the system as root or fldsup.
Step 2 Run the sysver command at the bash prompt:
LSnode:2#
sysver -mp | more
Step 3 In the resulting display, locate the chassis ID. (If you have two switch cards, the chassis ID should be the same for both.) The chassis ID is displayed in hex and looks something like this example:
0x08.0x00.0x14.0x56 (software chassis ID 5206)
- Record the pair of digits following each 0x. For the example above, you would record:
08001456
- If you have changed the modem init string and modem password from the factory defaults, record them as well, as you will need to restore them later.
Removing the Midplane
Step 1 Perform an orderly shutdown of the system, as described in the section "Performing an Orderly Shutdown".
Step 2 Cut off the power to the system by detaching the power cord or turning off the power feed.
Step 3 Remove all the cards from the front of the chassis.
Step 4 From the rear of the chassis, unseat all the access cards and disconnect the console/modem assemblies. (It's not necessary to remove these items from the chassis.)
Step 5 From the rear of the chassis, remove the NP access card(s). Behind each NP access card, at the bottom of the slot, you'll see a ribbon cable attached to the midplane. Disconnect each ribbon cable. (If you have two NPs---and thus two ribbon cables---you should label the cables so you can reconnect them properly later.)
Step 6 From the rear of the chassis, remove the lower power tray. (See the section "Replacing a Power Tray" for instructions.)
Step 7 Reach into the lower power tray slot and unplug the two power connectors (J15 and J16) from the midplane power tab, as shown in Figure 3-12.
Step 8 From the front of the chassis, remove four #2 Phillips-head screws from the top and bottom of the frame surrounding the card cage. (See Figure 3-13.) The screws are located behind slots 3 and 7.
Step 9 Reach into the chassis and remove two #2 Phillips-head screws from the top and bottom corners of left side of the midplane. (Figure 3-13 shows the positions of the screws on the midplane.) The midplane is now disconnected from the chassis.
Step 10 Pull the card cage (with the midplane still attached at the rear) out of the chassis. As you remove this assembly, rotate it slightly clockwise to allow the power tab to clear the chassis. (See Figure 3-14.)
Step 11 To separate the midplane and card cage, remove all the Phillips-head screws from the back of the midplane.
Figure 3-12 : Rear view of chassis showing power connectors as they connect to midplane power tab. (The internal bulkhead that separates the card cage on the left from the power tray slot is not shown.)
Replacing the Midplane
Step 1 Screw the replacement midplane to the card cage.
Step 2 Slide the midplane-card cage assembly into the chassis, holding the assembly so that the midplane enters with the power tab foremost. When the power tab clears the corner of the disk housing, rotate the assembly counterclockwise until it fits snugly.
Step 3 Replace the two screws at the left corners of the midplane.
Step 4 Replace the four screws in the top and bottom of the frame surrounding the card cage.
Step 5 Reinsert the line cards, NPs and switch cards into the chassis.
Step 6 From the rear of the chassis, reach into the lower power tray slot and reconnect plugs J15 and J16 to the midplane power tab. (The plugs are keyed to their sockets so that they cannot be connected incorrectly.)
Step 7 Replace the lower power tray.
Step 8 Locate the ribbon cable(s) behind the NP access card(s) and reconnect the cable(s) to the midplane. (There is one cable per NP.)
Step 9 Reconnect the console/modem assemblies and reseat the access cards; be sure to tighten all the retaining screws.
Note When you complete this procedure, check the front and back of the system to see that all boards, disks, blowers, bulkheads, filler panels, and covers are in place and firmly screwed to the chassis frame. When all these items are in place, they form an enclosure that prevents the escape of electro-magnetic interference and maintains air flow through the chassis.
Figure 3-13 : Midplane.
Figure 3-14 : Midplane/card cage assembly slides into the chassis with a twist.
Writing the Chassis ID to the New EEPROMs
This procedure differs depending on whether your system has one switch card or two. If you have two switch cards, you need only type two commands to program the two EEPROMs. If you have just one switch card, you must move the card from one switch slot to the other between commands. This is necessary because each midplane EEPROM is connected to one switch card slot, and you can't program the EEPROM without a switch card in the slot. It is very important to have the same chassis ID on both midplane EEPROMs.
Step 1 Power up the system.
Step 2 Attach a terminal to the console port of the active switch card.
Step 3 The terminal connects to the TCS hub. At the prompt, type the following command, replacing the placeholder at the end with your chassis ID, which you recorded at the beginning of this section:
TCS HUB<<A>>
set sa mid nodeaddr <chassisID>
Note This command assumes you are programming the EEPROM for switch slot A. If you wish to begin with slot B, begin the command with set sb instead of set sa.
Step 4 To verify that you entered the chassis ID in slot A correctly, type the following command and check the chassis ID in the resulting display. (If you just set the chassis ID for slot B, begin this command with show sb instead of show sa.)
TCS HUB<<A>>
show sa mid nodeaddr
Step 5 If this system contains two switch cards, skip to step. If this system contains only one switch card, type the following:
TCS HUB<<A>>
set sa power off
Note Again, this command assumes you are programming the EEPROM for switch slot A. If you wish to begin with slot B, begin the command with set sb instead of set sa.
Step 6 Remove the switch card from the chassis and put it into the other switch card slot.
Step 7 From the rear of the chassis, move the console/modem assembly (keeping the console connection intact) to the other switch card slot. Note that when you return to the console, the TCS hub prompt changes from A to B (or from B to A, if you started with switch slot B). Press [Return] to display the new prompt.
Step 8 At the console, type the following:
set sb mid nodeaddr <chassisID>
Note This command assumes you are programming the EEPROM for switch slot B. If you are doing slot A, begin the command with set sa instead of set sb.
Step 9 To verify that you entered the chassis ID in slot B correctly, type the following command and check the chassis ID in the resulting display. (If you just set the chassis ID for slot A, begin this command with show sa instead of show sb.)
show sb mid nodeaddr
Step 10 If the modem initialization string and modem password stored in midplane EEPROMs have not been changed from the factory defaults, skip to the next step. If the modem information has been changed, you must bring the new midplane up to date. Refer to the LightStream 2020 Network Operations Guide for instructions on programming the modem init string and password into the EEPROMs on the new midplane.
Step 11 To reset the system with the new EEPROM information, use the command shown below. Replace <slot#> with the slot number of the NP (1 or 2). If your system has two NPs, repeat this command for the second one.
reset <slot#>
Step 12 You can now bring the system up. To connect to the primary NP, use the command shown below. Replace <slot#> with the slot number of the active NP in the system (1 or 2).
connect <slot#>
Replacing a Console/Modem Assembly
This section tells you how to remove and replace a console/modem assembly.
A console/modem assembly is located behind each switch card, at the rear of the chassis. The assembly consists of a bulkhead with console and modem ports mounted on it, with cables to connect to the midplane.
Removal
Step 1 Loosen the retaining screws at the top and bottom of the bulkhead.
Step 2 Pull the bulkhead away from the chassis (see Figure 3-15). You'll see a ribbon cable that attaches the bulkhead to the midplane; disconnect it at the midplane end.
Replacement
Step 1 Connect the new assembly's ribbon cable to the connector on the midplane.
Step 2 Line up the bulkhead against the card cage and tighten the top and bottom retaining screws.
Note When you complete this procedure, check the front and back of the system to see that all boards, disks, blowers, bulkheads, filler panels, and covers are in place and firmly screwed to the chassis frame. When all these items are in place, they form an enclosure that prevents the escape of electro-magnetic interference and maintains air flow through the chassis.