Replacing an RDMA/AOC Cable

Impact on the System

During the replacement of a cable, the system switches services from the port of the cable to another redundant port.

• For front-end and scale-out links, if available links are unable to carry the current service load, the service I/O response latency increases and the system performance deteriorates. If there are no other redundant links, services run on a single link and the system reliability decreases.
• For back-end links, disks in a loop run on a single link and the system reliability decreases.

Prerequisites

• The spare part is on hand.
• The cable that you want to replace has been located.

• Data has been backed up before you replace the cable in online mode.

Precautions

• Remove and insert a cable with even force. Excessive force may damage the appearance of the cable or cause faults.
• Do not frequently remove and insert a cable. Wait at least 15 seconds between removal and insertion.

Tools and Materials

• ESD wrist strap
• ESD bag
• Labels

Procedure

1. Perform a pre-replacement check.
   1. Check system status.

      Start SmartKit and choose Home > Storage > Routine Maintenance > Health Check. On the Health Check page, perform inspection as instructed. For details, see Checking System Status.

      If any items fail the inspection, rectify the faults by performing the recommended actions in the inspection reports. Ensure that all other parts except the parts to be replaced are working properly.

   2. Check the status of the parts to be replaced.

      Start SmartKit and choose Home > Storage > Parts Replacement > Parts Replacement. On the Parts Replacement page, click FRU Replacement. Then complete the check before the replacement as prompted. For details, see Replacing an FRU.

      You can proceed to next steps only when all items pass the pre-replacement check and the replacement page is displayed. If any item fails, rectify the fault as prompted.

2. Wear an ESD wrist strap.
3. Hold the cable and push the connector slightly inwards, as shown in Figure 8-74.
   Figure 8-74 Pushing the cable connector inwards
   

4. Hold the plastic ring and pull it out in the arrow direction until the cable is unlocked, as shown in Figure 8-75 and Figure 8-76.
   Figure 8-75 Top view of removing a cable
   
   Figure 8-76 Bottom view of removing a cable
   

5. Pull the cable connector out of the port and put it into an ESD bag.
6. Take the spare part out of its ESD bag.
7. Insert the spare part vertically into the original position, as shown in Figure 8-77.
   Figure 8-77 Connecting a cable
   

8. Check the status of the port indicator to determine whether the cable has been successfully installed.
   • If the indicator is steady green or blue, the cable has been successfully installed.
   • If the indicator is steady yellow or off, the newly installed cable is faulty, the cable slot is faulty, or the cable is incorrectly installed.

9. Confirm the replacement.
   1. Perform a post-replacement inspection.

      After the parts replacement, return to the SmartKit page and click Replaced. Then complete the check after the replacement as prompted.

   2. Check system status.

      On the Parts Replacement page, click Inspection to check the system status again. If any item fails inspection, rectify the fault based on the suggestions in the inspection report.

   3. After the preceding procedure is complete, check services on the host for storage-related errors.

Follow-up Procedure

After the RDMA cable is replaced, label it to facilitate subsequent operations.