Before the DR service configuration, you need to check the application environment and storage at the production and DR sites where the protected objects reside, to ensure the normal running of subsequent configuration tasks.
Common Check Items
The following configuration items must be checked and configured on databases at both the production and DR ends.
- If the host where the openGauss database resides runs Linux, check the disk mapping mode using UDEV.
When UDEV is used to map disks, the restrictions on UDEV disk mapping modes are as follows:
- Only disk partitions can be used for UDEV disk mapping.
- When UDEV is used to map cm_vote, cm_shared, dss_shared, and dss_private_0 disks, only UDEV disks can be used as disks of their disk groups.
cm_vote: CM voting disk, one for each cluster
cm_shared: CM data disk, one for each cluster
dss_shared: database data disk, one or more for each cluster
dss_private_0: database xlog disk, one for each cluster
- Check the cluster authentication.
During the creation of an openGauss protected group, users can perform cluster authentication. Authentication requires that the user names and passwords of all nodes in the cluster at the production site and DR site be the same.
Check Items at the Production and DR Ends
- Log in to the active node of the openGauss cluster and run the following command to switch to the cluster user.
su - omm
- (Optional) Run the following command to load the environment variables.
source xxx
xxx indicates the file name of the environment variable to be loaded. If environment variables are separated during openGauss installation, you need to load environment variables separately.
- Run the following command to check whether the cluster status is normal. If the value of cluster_state is Normal, the cluster is normal.
cm_ctl query -Cvipd
Perform the check on the production end. The following information is displayed:
[ CMServer State ] node node_ip instance state ----------------------------------------------------------------------------- 1 node3.38.232 8.xx.xx.232 1 /opt/omm/install/cm/cm_server Primary 2 node4.38.233 8.xx.xx.233 2 /opt/omm/install/cm/cm_server Standby [ Defined Resource State ] node node_ip res_name instance state ---------------------------------------------------------- 1 node3.38.232 8.xx.xx.232 dms_res 6001 OnLine 2 node4.38.233 8.xx.xx.233 dms_res 6002 OnLine 1 node3.38.232 8.xx.xx.232 dss 20001 OnLine 2 node4.38.233 8.xx.xx.233 dss 20002 OnLine [ Cluster State ] cluster_state : Normal redistributing : No balanced : Yes current_az : AZ_ALL [ Datanode State ] node node_ip instance state | node node_ip instance state -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- 1 node3.38.232 8.xx.xx.232 6001 19339 /opt/omm/install/data/dn P Primary Normal | 2 node4.38.233 8.xx.xx.233 6002 19339 /opt/omm/install/data/dn S Standby Normal
Perform the check on the DR end. The following information is displayed:
[ CMServer State ] node node_ip instance state ----------------------------------------------------------------------------- 1 node5.38.234 8.xx.xx.234 1 /opt/omm/install/cm/cm_server Standby 2 node6.38.235 8.xx.xx.235 2 /opt/omm/install/cm/cm_server Primary [ Defined Resource State ] node node_ip res_name instance state ---------------------------------------------------------- 1 node5.38.234 8.xx.xx.234 dms_res 6001 OnLine 2 node6.38.235 8.xx.xx.235 dms_res 6002 OnLine 1 node5.38.234 8.xx.xx.234 dss 20001 OnLine 2 node6.38.235 8.xx.xx.235 dss 20002 OnLine [ Cluster State ] cluster_state : Normal redistributing : No balanced : Yes current_az : AZ_ALL [ Datanode State ] node node_ip instance state | node node_ip instance state -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- 1 node5.38.234 8.xx.xx.234 6001 19339 /opt/omm/install/data/dn P Main Standby Normal | 2 node6.38.235 8.xx.xx.235 6002 19339 /opt/luwang/install/data/dn S Standby Normal
Storage End
Check whether the synchronous replication status of the xlog disks is normal.
Table 1 describes the storage environment requirements of disaster recovery solutions.
Technology |
Restriction and Requirement |
|---|---|
Synchronous Replication (SAN) |
|