Fault Domain Configuration and Management

Upgrade and Configuration Items

Cluster-level Configuration

Enabling fault domains requires adding cluster-level configuration, otherwise it cannot be distinguished. Adding a new zone is a fault domain zone or belongs to the original cross_zone.

FaultDomain               bool  // Default is false

Volume-level Configuration


crossZone        bool  # Cross-zone


default_priority  bool  # True means prefer the original zone rather than allocating from the fault domain

Configuration Summary

  1. For existing clusters, whether self-built or community-built, whether single zone or cross-zone, if fault domains need to be enabled, the cluster needs to support it, the master needs to be restarted, the configuration needs to be updated, and the policy for updating existing volumes needs to be managed. Otherwise, continue to use the original policy.
  2. If the cluster supports it but the volume does not choose to use it, continue to use the original volume policy and allocate resources according to the original policy in the original zone. Use new zone resources when existing resources are exhausted.
  3. If the cluster does not support it, the volume cannot enable its own fault domain policy.
Cluster:faultDomainVol:crossZoneVol:normalZonesFirstRules for volume to use domain
NN/AN/ADo not support domain
YNN/AWrite origin resources first before fault domain until origin reach threshold
YYNWrite fault domain only
YYYWrite origin resources first before fault domain until origin reach threshold


Fault domains solve the problem of copyset distribution without planning in multi-zone scenarios, which affects the durability of data, but existing data cannot be automatically migrated.

  1. After enabling fault domains, all devices in the new region will be added to the fault domain.
  2. The volume created will prefer the resources of the original zone.
  3. When creating a new volume, use the domain resources according to the configuration items in the table above. By default, if available, the original zone resources are used first.

Management Commands

Create a volume using fault domains

curl ""

Parameter List

crossZonestringWhether to cross zones
normalZonesFirstboolNon-fault domain priority

Check if Fault Domain is Enabled

curl ""

Check Fault Domain Usage

curl -v  ""

Check the usage of fault domain copyset groups

curl ""

Update the upper limit of non-fault domain data usage

curl ""
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