HANA Consistency check

HANA Consistency check –Technical Consistency Check:

In this Blog we will explain the further process steps for the SAP Hana consistency check.

Recall Previous Part1 session:
Previously we have explained the SAP HANA consistency checks details and command for SAP HANA consistency check.

1. Metadata consistency:
2. Row and column store consistency:
Column store consistency:
Row store consistency:
3. Persistence check:
4. Backup Checks
5. Existence of the page dumps
6. SAP HANA Binaries
7. Topology consistency:
8. SAP HANA Installation consistency:
9. Virtual tables consistency check:

Previous session Meta data consistency and Row and column store consistency check details we have explained. We will continue for further consistency check.

HANA Consistency check Part2:

3.Persistence check:

• Data backups (Full Backup) automatically check the Persistency pages for corrections. If inconsistency happened then Backup has failed with errors.
• Backup based on storage snapshot(Data snapshot) don’t provide the this consistency check.
• SAP HANA2.0 SP3 log backups consistency check option is available.
• hdbpersdiag tool using we will check the manually checking the consistency of the persistence
• using hdbpersdiag tool check the analyze physical corruptions of the persistent storage.
• So we can check the consistency of the storage snapshot backups of SAP HANA data volumes.
• We can use check all option to verify the state of the sap HANA data volumes –Persistence
Using the hdbpersdiag Tool:
• Using this we can check the SAP HANA Database consistency check for Data volume
• Goto the below path
• cd Using the hdbpersdiag Tool
• # hdbpersdiag
• check all <data_volume_path>
• When you wll perform the consistency check then you can stop the SAP Application for avoid issue.
• More consistency check-Please check 2272121
• Starting with SAP HANA 2.0 SPS 05 this tool can officially be used for a persistence check
• Some cases pages is fine on persistence level but inconsistency happened on memory level. In the worst case this can result in corruptions when data is loaded into memory
• In this case, we will check Backup and memory based consistency check CHECK_TABLE_CONSISTENCY

4.Backup Consistency check:

• Consistency of the database backups, we will check using the hdbbackupcheck tool.
• Please check the sap note for more details for Backup consistency check using hdbbackupcheck tool.
• Another tool also available for Backup consistency.
• Using hdbbackupdiag –check tools, we can check the available Hana database checks.
• Using this verify the hana database consistency check—if nackup consistency is fine then we can use the existing backup to Restore the another system.
• Please check sap note: 1873247

5. Existence of page dumps Consistency check:

• The Existence of page dumps can indicate page corrections.
• Please check the sap note 1977242.

6. SAP HANA Installation Consistency check:

• The installation consistency option is available on HANA1.0SP12.
• This will be check the File system, permission and settings will check.
• Go to the installation path and execute the below command for check the sap hana installation consistency check.
• hdblcm –action=check_installation
• More sap hana installation consistency check 2365649.

7. Dynamic Tiering: Consistency check:

• This consistency option is available Hana2.0 SP00
• Using the this option we can check the dynamic tiering Consistency using CHECK_ES for procedure.
• ACTION : Type of action (e.g. CHECK, VERIFY, ALLOCATION, ALLOCATION_LEAKED_BLOCKS, ALLOCATION_DUPLICATE_BLOCKS, ALLOCATION_UNALLOCATED_BLOCKS, DROPLEAKS)
TYPE : Object type (e.g. INDEX, DATABASE, TABLE, PARTITION, COLUMN, DBSPACE)
NAME : Name of analyzed object (NULL for all objects)
RESOURCE_PERCENTAGE: Number of threads per CPU in percent (default: 100 %, i.e. 1 thread per CPU)

                CALL CHECK_ES(‘ACTION’, TYPE , OBJECT_NAME, RESOURCE_PERCENTAGE)

Example : (check for all tables with 50 % threads)
CALL CHECK_ES(‘CHECK’, ‘TABLE’, NULL, 50)

8. Virtual tables consistency check:

• This consistency option is available Hana2.0 SP00
• Using the this option we can check the Virtual tables consistency check using CHECK_VIRTUAL_TABLES for procedure.
• Commands:
• CALL CHECK_VIRTUAL_TABLES(‘CHECK’, ‘SCHEMA’, TABLE_NAME)

9. Topology Consistency Check:

• This consistency option is available Hana2.0 SP05
• Using the this option we can check the Virtual tables consistency check using Below command.
• CALL CHECK_TOPOLOGY_TREE(‘action’)
• The following Topology consistency is available in Hana data ACTION=
CHECK : Global check of nameserver topology
REPAIR : Repair of inconsistencies that can be automatically corrected
CHECK_DATABASE_FIELDS_VALIDATOR : Checks if all databases have all mandatory fields in the topology
CHECK_DATABASE_STATUS_VALIDATOR : Checks the status of databases
CHECK_FAILOVER_HOST_ROLES_VALIDATOR : Checks if all possible failover candidates have all required roles

Conclusion:

In this blog we have successfully explain the two parts of sap Hana database consistencies checks steps and process details.

SAP HANA  Consistency check Part1
SAP HANA  Consistency check Part2

We have explained the few Key consistency checks and process only. Please check latest SAP Notes for the SAP HANA Consistency check notes for More knowledge on SAP HANA database consistency check.

1977584 – SAP HANADATABASE Technical consistence check
2628775 – Log Segment Consistency Check During Log Backup
2843934 – Persistence Consistency check
2116157 – SAP HANA Database Consistency Checks and Corruptions details.

FAQ for SAP HANA Database Consistency;

1. Which procedure we can check Hana database Consistency check?
Using the below procedure, we can check the sap Hana database consistency check.
CHECK_TABLE_CONSISTENCY
CHECK_CATALOG

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