Huawei OceanStor S2600 V3 Controller Write Cache Disabled

Reference

Reference link (support.huawei.com)

Problem description

    2600 V3R5C00: The upper-layer application reports slow write IO with 50ms latency. Storage logs show that write cache is disabled on both controllers.

Alarm information

    2019-05-24 06:58:23    0xF00C90015    Major    None    Write cache of controller (Controller Enclosure  CTE0, controller B) is disabled.
     2019-05-24 06:58:23    0xF00C90015    Major    None    Write cache of controller (Controller Enclosure  CTE0, controller A) is disabled.  

1. The logs show that the current LUN write policy is write-through.

2. The logs show an alarm indicating excessive temperature of the controller enclosure at the time when the write cache error occurred.

3. The device has returned to normal operation. You can execute commands to restore the write cache policy.

Enter the command "show controller general" to confirm whether both controllers in the controller enclosure are OK.

Enter developer mode (change user_mode current_mode user_mode=developer)

First, enter "change system write_through_policy write_through_switch=Disable",

Then, enter "change system write_through_policy write_through_switch=Enable"