This topic describes frequently asked questions about OceanBase tenant management.
Supported features
Q1: Can I modify the tenant name?
A: No, you cannot modify the tenant name in OCP. You must confirm the name when you create a tenant. The name cannot be modified afterward.
Q2: Does OCP support concurrent control on the business traffic of a tenant ?
A: No, OCP does not plan to support this feature.
Q3: Can I retrieve the password of the Oracle sys tenant created in OCP?
A: Yes. In versions earlier than OCP V2.5.1, you can retrieve the cipher file in the Password Box of OCP and contact OceanBase technical support to decrypt the cipher file. In OCP V2.5.1 and later versions, OCP supports password reset. We recommend that you reset the password if you forget it.
Display
Q1: What can I do if the corresponding page is not displayed after I click TopSQL under a tenant?
A: We recommend that you use Google Chrome 88 or later.
Manage tenants
Q1: How many connections can I reasonably set for a single OceanBase tenant?
A: At present, if the number of connections you created for an OceanBase tenant exceeds a threshold, an alert is triggered. It does not cause other issues. The maximum number of connections allowed for a single OBServer is 256,000.
Q2: My OceanBase cluster has three zones. After I use OCP to delete a replica of a tenant, an error occurred when I attempt to add a new replica to the tenant. Error message: An error occurred while operating on OceanBase Database. Error: tenant already exists . What is the cause of this problem?
A: It is a problem of the underlying-layer recycling strategy. We recommend that you wait for a while and try again.
Q3: OCP authorizes only read-only roles to manage Unit specifications. Is this expected?
A: At present, only read-only users can perform a non-destructive operations. Whether to disable the modification privilege of readable users will be discussed in the subsequent design.
Q4: The tenant recycle bin created by OCP was enabled by default, but now it is disabled by default. Is the change made by OceanBase Database or OCP?
A: The change is made by OceanBase Database, because enabling the recycle bin will cause issues in OceanBase Database.
Q5: I have deleted a database, but it is still displayed in the tenant management list. Why ?
A: This list is updated once per day and is not updated in real time.
Q6: How can I delete the tenant specifications that I do not need after I create them?
A: In the MetaDB, execute the DELETE FROM ob_unit_spec WHERE `name` = 'test' AND type = 'CUSTOM'; statement. Replace text with the specification name.
Create and delete tenants
Q1: How can I create an Oracle tenant with the GBK character set?
A: Execute the vi /home/admin/obztools_agent/src/task/obauto_plus/ob_operate_plus.py statement 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)
# In the create_tenant function, add this line to set the GBK character set.
sql_tenant += ", charset=gbk"
Q2: Why is the tenant status displayed as TENANT_STATUS_DROPPING after I delete the tenant by using a CLI tool?
A: The tenant will be deleted seven days later after you delete it by using a CLI tool.
Tenant scaling
Q1: How can I scale up or scale out a tenant?
A: You can scale up the tenant by adjusting the Unit specifications of the tenant replica or scale out the tenant by adjusting the number of Units under the current zone of the tenant replica on the Overview page of the tenant.
Q2: Does OCP determine the unit to delete when I scale in a tenant? Can I specify a unit to delete?
A: No, only the administrator has the privilege to determine the unit to delete. If your account has the administrator privileges, you can go to the Topology page of the tenant and select a unit to delete.
Q3: What can I do if I fail at the Wait alter resource... step when I reduce the number of units in a tenant?
A: Contact OceanBase technical support to solve the problem.
Q4: An error occurred when I was adjusting the unit of a tenant. Error message: The {0} tenant does not support this operation in the current status. What is the cause of this problem?
A: Maybe the tenant is in the Maintaining state because a task is being run to modify the tenant.
Performance and monitoring
Q1: I cannot query the second business user that is created by the Oracle tenant based on the schema in the Resource Management column of the OCP tenant. However, the business user can be seen in other monitoring information. Why?
A: The resource trend is updated at 05:00:00 each day. You cannot view the resource trend of tenants that you created or migrated before 05:00:00. If you do need to view such information, manually run the following command:
# Replace the following fields with the actual values in the following curl command, modify the collectTime parameter, and then run 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 utilization in OceanBase Cloud Platform > Tenants > xx Tenant > Resource Management calculated?
A: Refer to the following statement:
gv$sysstat:
SELECT * from gv$sysstat WHERE con_id=tenant ID AND `name` LIKE '%cpu%'
Q3: What does the time in the Concurrency Latency column on the TopSQL tab of the SQL Diagnosis page mean?
A: The wait time during the SQL execution process.