This topic describes common questions about OceanBase tenant management.
Feature support
Q1: Is it supported to modify the tenant name?
A: In OCP V4.3.2, the feature to rename tenants is supported. For more information, see Rename a tenant.
Q2: Does OCP support concurrent control of business traffic for a specific tenant?
A: No, and there are no plans to support this feature.
Q3: The sys password of an Oracle tenant created in OCP is lost. Does OCP support password recovery in this case?
A: Yes, for OCP earlier than V2.5.1, you can find the ciphertext of the password in Password Box of OCP and contact technical support personnel to obtain the decryption method. For OCP V2.5.1 and later, the ability to reset the password is provided, which is more recommended.
Display issues
Q1: After I click TopSQL in the tenant list, the corresponding page cannot be displayed. What could be the reason?
A: We recommend that you upgrade your browser to Chrome 88.
Tenant management
Q1: What is a recommended value for the maximum number of connections for a single OceanBase tenant?
A: The concept of connections at the tenant level of OceanBase Database has no practical significance and only affects alerts in OCP. The significant value is 256,000, which is the maximum number of connections supported by a standalone OceanBase instance.
Q2: I deleted a replica of a tenant in an OceanBase cluster with three zones and then created a new replica in this tenant. However, the new replica was failed to be created and an error Operation on OB failed, error message: tenant already exist was returned. What could be the reason?
A: This is caused by the underlying recycle strategy of OceanBase Database. We recommend that you wait for a while.
Q3: Is it expected that a user with only the read-only privilege can manage the specifications of the tenant in OCP?
A: Currently, the design allows read-only users to perform some non-destructive operations. Whether to revoke the modification privilege of read-only users is still under discussion.
Q4: The tenant recycle bin in OCP is disabled by default in earlier versions. Is it a kernel-level change of the default configuration, or an OCP-level change?
A: The change is made at the kernel level. The tenant recycle bin cannot be enabled because it will cause some issues in OceanBase Database.
Q5: Why are deleted databases still displayed in the tenant's resource management section?
A: The data is refreshed in the database on a daily basis and the data is not updated in real time.
Q6: How do I delete a wrong tenant specification?
A: Execute the DELETE FROM ob_unit_spec WHERE `name` = 'test' AND type = 'CUSTOM'; statement in the MetaDB database, where test is the name of the specification.
Q7: After I modified the tenant name in a dark screen, OCP reported that the tenant was unavailable and I received relevant alerts. What is the cause of this issue and how do I solve it?
A: After you modified the tenant name in a dark screen, OCP cannot identify the name and therefore reported that the tenant was unavailable and sent relevant alerts. You can use the same method to modify the tenant name back to the original name in a dark screen, and then use the Rename feature of OCP.
Tenant creation and deletion
Q1: How do I create an Oracle tenant that uses the GBK character set?
A: Run vi /home/admin/obztools_agent/src/task/obauto_plus/ob_operate_plus.py to modify the ob_operate_plus.py file.
def create_tenant(tenant_name, primary_zone, resource_pool_list, obregion_name, rs_list=[], white_list='%', locality=None, tenant_mode=None):
if primary_zone is None or 0 == len(primary_zone):
sql_tenant = "create tenant {0} resource_pool_list=('{1}')".format(tenant_name, "', '".join(resource_pool_list))
else:
sql_tenant = "create tenant {0} primary_zone='{1}',resource_pool_list=('{2}')".format(tenant_name, primary_zone, "', '".join(resource_pool_list))
if locality is not None:
sql_tenant += ", locality='{0}'".format(locality)
# Add this line in the create_tenant function to set the character set to GBK.
sql_tenant += ", charset=gbk"
Q2: After I delete a tenant in the console, its status remains TENANT_STATUS_DROPPING. What's wrong?
A: It takes about 7 days to delete a tenant that is removed in the console.
Tenant resource management
Q1: How do I scale up a tenant?
A: On the Overview page of the tenant, you can increase the specifications of the unit (vertical scaling) or add units (horizontal scaling).
Q2: Does OCP decide which unit to delete when I shrink a tenant? Can I delete a specified unit?
A: No. You can go to the Topology page of the tenant and delete a specified unit.
Q3: What causes the task to fail at the Wait alter resource... step when I reduce the number of units of a tenant?
A: Contact technical engineers of OceanBase Kernel for support.
Q4: What causes the error The specified tenant xxx is in an unsupported status for this operation when I adjust the units of a tenant?
A: Another task that modifies the tenant is not completed, so the tenant is being maintained.
Q5: When I create or modify a tenant, I cannot select a small unit, such as the 0.5C2GB unit. How do I solve this issue? A: If the OceanBase version is V2.0.0 or later, by default, a tenant whose memory resource of the unit is less than 5 GB cannot be created or modified. Specifically, when you create a tenant or modify the specifications of a tenant, small units are not listed in the drop-down list. In specific scenarios such as non-production environments like demo scenarios, if the OCP version is V2.5.1 or later, you can remove this restriction by modifying the OCP system parameters. The method is as follows:
Connect to MetaDB.
Execute the following SQL statement to set the value of ocp.operation.ob.tenant.allow-small-unit in the config_properties table to true.
update ocp.config_properties set value = 'true' WHERE `key` = 'ocp.operation.ob.tenant.allow-small-unit';
Performance and monitoring
Q1: In the resource management section of an OCP tenant, I cannot query for the second business user created in an Oracle tenant, but this user can be seen in other monitoring metrics?
A: Resource trend data is collected daily at 5 AM. Therefore, you cannot view the resource trends of a tenant created or migrated on a day before 5 AM of that day. If necessary, you can run the following command to manually trigger the collection.
# Replace the actual values in the following curl command with the corresponding placeholders and modify collectTime, and then directly execute the curl command.
#SITE_URL=http://xxx.xxx.xxx.xxx:8080
#CLUSTER_ID=1
curl -i --location --request POST \
"
${SITE_URL}
/api/v2/ob/clusters/
${CLUSTER_ID}
/collectDailyMetric" \
--header 'Content-Type: application/json' \
--header 'Authorization: Basic YWRtaW46cm9vdA==' \
-d '{
"
collectTime
":"2020-11-10T00:00:00Z",
"aggAheadSeconds": 300
}'
Q2: How is the CPU usage collected in the "OceanBase Cloud Platform > Tenant > xx Tenant > Resource Management" section of OCP?
A: Refer to the following statement:
gv$sysstat:
SELECT * from gv$sysstat WHERE con_id=tenantID AND `name` LIKE '%cpu%'
Q3: What does the time spent in concurrent waits indicate on the TopSQL tab of the SQL diagnostics page for a tenant?
A: The time spent waiting during SQL execution.