Enabling Autostart of sap hana database on server boot situation

There are multiple ways to achieve the auto start of HANA after a server reboot situation.

If you want to enable AUTOSTART option for your HANA database after a server reboot situation then you can do it with editing the following file…


1. Logon the linux operating system with adm user

2. Go to /hana/shared/#SID#/profile/ location

3. Edit the file #SID#_HDB#INSTANCE_NUMBER#_#HOSTNAME#

vi /hana/shared/$SAPSYSTEMNAME/profile/$SAPSYSTEMNAME_HDB*

4. Change the parameter “Autostart = 0″ to “Autostart = 1″

5. Save

Next reboot , HANA database will be started automatically…

SQL message: rejected as server is temporarily overloaded

Problem: Even though there is no active jobs or load on the server, SAP Application dumps every transaction and SM21 logs the message "SQL message: rejected as server is temporarily  overloaded".

Reason: HANA enables a new feature with the new updates.

It uses the admission control feature to apply processing limits and to decide how to handle new requests if the system is close to the point of saturation.

You can apply thresholds using configuration parameters to define an acceptable limit of activity in terms of the percentage of memory usage or percentage of CPU capacity.

Limits can be applied at two levels so that firstly new requests will be queued until adequate processing capacity is available or a timeout is reached, and secondly, a higher threshold can be defined to determine the maximum workload level above which new requests will be rejected. If requests have been queued, items in the queue are processed when the load on the system reduces below the threshold levels. If the queue exceeds a specified size or if items are queued for longer than a specified period of time they are rejected.

In the case of rejected requests an error message is returned to the client that the server is temporarily overloaded: 1038,'ERR_SES_SERVER_BUSY','rejected as server is temporarily overloaded'.

Resolution: Under SystemDB -> configuration -> indexserver.ini ->admission_control:enable: Set to False

HDBUSERSTORE pointing to wrong hostname

Details: SAP is installed with alias name. Hdbuserstore always points to alias name, but instead I wanted it to point to the hostname to which it is required.

Solution:

The snote that is helpful to resolve this issue is 2120226 - SAP HANA client software and entries in hdbuserstore when using virtual host names for SAP application servers.

Under the /usr/sap/SAPSID/hdbclient/install , there is a file "installation.ini" .
Modify the parameter - Hostname=<hostname/aliasname>

This will redirect the command "hdbuserstore list" to look for the correct directory and key files.

If it is only HANA , then the location of the hdbuserstore is always pulled from the environment variables.

Eg: Check for the following env variables 

    HDB_USE_IDENT 

   or from /hana/shared/(SID>/HDBXX/home/.sapenv.csh or .sapenv.sh

Crontab

Came across the following website which is helpful in setting the cron job conditions. Give your inputs and it will show on what data/time is the job going to occur.

https://crontab.guru/

SAP Client Copy Profiles

Always, it has been a pain to search / understand what data is copied/deleted during a SAP client copy.

Most of the blogs online has the procedure to do a SAP Client copy. The following points are helpful in performing a client copy.

1. Take a backup of the Source Client. This is easier method to restore the application data as it is deleted with most of the profiles.
2.  Try to do a Remote client copy as it does not require space on File system.

Copy Profile	Meaning	User Data	Customizing	Application data
SAP_USER	Users, user roles and authorization profiles are copied. The client is not reset.	Yes	No	No
SAP_CUST	Client-dependent Customizing, including authorization profiles, are copied. The application data is deleted and the user data is retained.	No	Yes	No (will be deleted)
SAP_UCUS	corresponds to SAP_CUST with master data	Yes	Yes	No (will be deleted)
SAP_ALL	All data belonging to a client, with the exceptions of change documents and local data, is copied.	Yes	Yes	Yes
SAP_APPL (as of SAP Web AS 6.10)	SAP_ALL without user master data	No	Yes	Yes