Help Center/ GaussDB(DWS)/ Tool Guide/ Server Tool/ DisasterFineGrained.py/ Command Reference/ Preparation Commands
Updated on 2025-01-09 GMT+08:00
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Preparation Commands

Function

The prepare command is used to set GUC parameters for the active/standby fine-grained DR cluster in one-click mode.

Syntax

python3 $GPHOME/script/DisasterFineGrained.py -t prepare --local-dn-num <localDnNum> --remote-dn-num <remoteDnNum> --config-file <configFile>

Parameter Description

Long Option

Short Option

Data Type

Description

Range

Default Value

Example

-t

N/A

String

The interface supports multiple functions. Set this parameter to prepare to prepare for the active/standby cluster.
  • -t generate-config
  • -t prepare
  • -t create-publication
  • -t alter-publication
  • -t cancel-publication
  • -t get-current-disaster

N/A

-t prepare

--local-dn-num

N/A

String

Number of DNs in the local cluster

N/A

N/A

--local-dn-num 6

--remote-dn-num

N/A

String

Number of DBs in the remote cluster

N/A

N/A

--remote-dn-num 3

--config-file

N/A

String

Path of the dual-cluster DR configuration file.

NOTE:

N/A

N/A

--config-file /home/userA/config.ini

Usage Guide

The prepare command must be executed on the active node of the active cluster.
Table 1 Configuring GUC parameters

Cluster

Parameter

Parameter Description

Value Range

Value

Active/Standby cluster

enable_metadata_tracking

In the primary cluster for fine-grained DR, this parameter is used to track metadata (including DDL and DCL) changes of objects related to fine-grained DR and synchronize changed metadata to the standby cluster.

Boolean

  • on indicates that the metadata change tracking function is enabled. Metadata changes can be synchronized to the standby cluster through fine-grained DR.
  • off indicates that the metadata change tracking function is disabled.

on

Active/Standby cluster

disaster_cluster_dn_nums

Specifies the number of DNs in the primary/standby cluster for fine-grained DR, in the format of Number of DNs in the local cluster,Number of databases in the remote cluster. This parameter is used for data bucketing during synchronization from a small cluster to a large cluster.

A string. Set this parameter based on DNs in the primary and standby clusters. For example, if the ratio of DNs is 6:3, set this parameter to 6,3 and 3,6 for large and small clusters, respectively.

Command line input

Standby cluster

view_independent

Enables or disables the view decoupling function.

Boolean

  • on indicates that the view decoupling function is enabled.
  • off indicates that the view decoupling function is disabled.

on

Example Command

Prepare the active/standby cluster.

python3 $GPHOME/script/DisasterFineGrained.py -t prepare --local-dn-num 3 --remote-dn-num 3 --config-file /home/mpp/mppcases_c10/cluster/gs_rch_DR-v6/test/backupRestore.ini

System Response

[perfadm@ecs-env-2988 test]$ python3 $GPHOME/script/DisasterFineGrained.py -t prepare --local-dn-num 3 --remote-dn-num 3 --config-file /home/mpp/mppcases_c10/cluster/gs_rch_DR-v6/test/backupRestore.ini
[Start ESL disaster fine grained process]
set guc 'enable_metadata_tracking' to 'on' on 192.168.250.152.
set guc 'disaster_cluster_dn_nums' to '3,3' on 192.168.250.152.
set guc 'enable_metadata_tracking' to 'on' on 192.168.244.53.
set guc 'disaster_cluster_dn_nums' to '3,3' on 192.168.244.53.
set guc 'view_independent' to 'on' on 192.168.244.53.
Success set guc prepare.
[Finished ESL disaster fine grained process]
Parent topic: Command Reference