Replacing a Cache Disk Module (OceanStor Pacific 9146 (One Node per Chassis, One CPU per Node)/OceanStor Pacific 9346/OceanStor Pacific 9546)

Impact on the System

• If a cache disk module is faulty, the system performance decreases by 30% to 35% but data consistency is not affected.
• During the replacement of a cache disk module, the system performance will decrease. Therefore, you are advised to replace a cache disk module during off-peak hours.
• During the replacement of a cache disk module, the data durability decreases during data reconstruction. After the reconstruction is complete, the data durability recovers.

Prerequisites

• The replacement cache disk module (spare part) has been prepared.
• The faulty cache disk module has been located. Figure 1, Figure 2, Figure 3, and Figure 4 show the slot numbers of cache disk modules.
  Figure 1 Slot numbers of cache disk modules on a one-node chassis with two CPUs per node
  
  Figure 2 Slot numbers of cache disk modules on a two-node chassis with two CPUs per node
  
  Figure 3 Slot numbers of cache disk modules on a one-node chassis with one CPU per node
  
  Figure 4 Slot numbers of cache disk modules on a two-node chassis with one CPU per node
  
• The disk pool to which the faulty cache disk module belongs is in the normal or degraded state.

Precautions

• To prevent replacement failures, ensure that the replacement cache disk module is free from obvious foreign objects, collision, and scratches.
• To prevent replacement failures, ensure that the cache disk slot is free from foreign objects or obvious damage before installing the cache disk module.
• To prevent system faults, use the BOM code of the faulty disk module to apply for a replacement disk module.
• When replacing a cache disk module, wait 10 seconds after it is removed before you install a new one.
• Remove cache disk modules in sequence. Remove one cache disk module completely before removing another.
• Install cache disk modules in sequence. Install one cache disk module completely before installing another.

When replacing a cache disk module, ensure that the time from removing the cache disk module to installing a new cache disk module into the node does not exceed three minutes. Otherwise, the heat dissipation of the storage device will be affected and the system will be faulty.

Tools and Materials

• ESD gloves
• ESD wrist strap
• ESD bag
• Labels

Procedure

1. Remove the disk module.
   

   • When removing disk modules, correctly record the slots where disk modules reside.
   • The time from disk module removal to installation and restoration cannot exceed three minutes. Otherwise, the system will be faulty due to overtemperature.
   1. Press the ejector release button on the disk module. The ejector lever automatically ejects. See (1) in Figure 5.
      Figure 5 Removing a disk module
      
   2. Hold the ejector lever of the disk module and pull out the disk module slowly. See (2) and (3) in Figure 5.

2. Put the removed disk module into an ESD bag.
3. Take the replacement disk module out of its ESD bag.
4. Install the disk module.
   

   Ensure that disk modules are inserted into the same slots before and after the replacement. Otherwise, services may be affected.

   1. Open the ejector lever completely and push the disk module into the node along the slot until it cannot move forward. See (1) in Figure 6.
      Figure 6 Installing a disk module
      
   2. Close the ejector lever of the disk module to push the disk module into the node with the force between the ejector lever and the node. See (2) in Figure 6.

Follow-up Procedure

After the cache disk is replaced, label it to facilitate subsequent operations.