Use of Virtual/Secondary host name with SAP HANA

There are scenarios where you do not connect to SAP HANA database instance directly via Host IP address or Physical hostname but via a Virtual IP or NAT address.

The main connection between NAT and the IP is established via DNS or a local entry in local host file.

But internally SAP HANA tries to make a connection to the Tenant DB using physical IP by default. Same has been depicted below with an example of SAP HANA Studio.

If you check the properties of a tenant database from studio you will see the following:

Even though you connect to DB using NAT IP (10.253.80.9) it is internally redirected to original IP (10.249.28.20) to make additional connections.

In this case when you try to make connection to a tenant database via webdispatcher or sql clients you will not be able to communicate to tenant DB.

studio1

You can also verify the same by querying M_HOST_INFORMATION.

studio2

This behaviour is controlled by parameter “public_hostname_resolution” under global.ini.

stud3

To change the behaviour you will have to change the parameter to “no” so that system is not forced anymore to use IP address of the Network interface. Instead you can map the hostname to required IP address as required.

settono

Note: This change does not required a DB restart.

Now you can map the hostname with required IP address on client machine to connect to the database:

Changes can be observed again with studio again.

afterc

 

 

SAP HANA Cockpit 2.0 – Installation and configuration

SAP HANA Cockpit is a Web-Based  tool for administration, monitoring and maintenance of SAP HANA systems.

Below we discuss installation steps and some key points with respect to cockpit:

  1. Download the required SAP file from SAP Market Place.cockpitdown
  2. Extract the SAR file and trigger installation using hdblcm.
    Note that installer installs a HANA instance (Express edition) of its own.
    More details hereco1
  3. Verify the details, enter the password and continue. Like any HANA installation user SYSTEM is created on the DB which will be used to login to Cockpit also.
    Along with SYSTEM, the other key user created is COCKPIT_ADMIN.
    co2.png
    Note that 51021 and 51023 are the default ports for Cockpit and Cockpit manager respectively.
  4. First it is required to login to Cockpit manager to assign yourself required roles using user COCKPIT_ADMIN.
    co3
    CO4
  5. Now you are ready to login to the HANA Cockpit.
    co5
  6. If you want to add additional users or resources (HANA systems) to cockpit, you can do so via SAP HANA Cockpit manager.
    co6
    co7

 

Important SAP Notes:

2496215 – You’re not authorized to open the SAP HANA Cockpit

2618617 – Launching SAP HANA Cockpit 2.5.5 in Firefox

2496215 – You’re not authorized to open the SAP HANA Cockpit

2185556 – FAQ: SAP HANA Cockpit

2595496 – Register a Resource in HANA Cockpit

2149157 – Unable to access the SAP HANA Cockpit due to error “Failure – Unable to load groups”.

 

AWS Certified Solution Architect – Points to remember (miscellaneous)

  1. Simple Queue Service.
    Use Visibility Timeout parameter to avoid duplication of message being processed.
    By Default AWS uses short polling which could incur unnecessary cost to empty response polling.
    Long polling should be used to avoid this.
    ReceiveMessage call sets WaitTimeSeconds to 0.
  2. Simple Notification Service usage.
  3. Simple Workflow Service Usage.
  4. Redshift is a Database Warehouse service.
  5. Uses block size of 1 MB. Compared to other databases which use 2 KB to 32 KB much more efficient and reduces IO’s.
  6. Kenesis is used for streaming data.