SAP HANA SM21 error SQL 10821

[#1]

Hi Experts,

We have a HANA System replication setup with SAP ABAP on Primary HANA, since past few hours there are continuous error logs in SM21 with below details, the system replication connectivity, network connection etc all works fine, does anyone know the cause of this error. These errors are with respect to the secondary HANA database system.

HANA 1 SP12

SAP system ECC 6 EHP7

Thanks in advance

Vijish

[bryan_bingay]

I think that is a good place to start. Also think about getting HANA Cockpit installed and all your HANA systems registered to it. SAP has depreciated HANA Studio and adding new features only to HANA Cockpit.

Think about a HA/DR provider for automatic failover like, SAP HANA System Replication Scale-Up - Performance Optimized Scenario | SUSE Linux Enterprise Server...; this is what we use. I just went through a HW and HANA upgrade to 25 HANA systems. Four of the systems, ECC, CRM, BW and Solution Manager are a 2 node scale-up SLES 15 SP1 HANA 2.0 SPS05. It took a lot of planning and testing. Hopefully the BASIS team has a good working relationship with the sysadmins and network team, you are going to need their help.

Good luck

Bryan

[avijish]

Hi Bryan, Thanks for sharing your experience. Will consider the HA/DR as recommended in the upcoming HANA Upgrade. By the way the issue I had is resolved now. the Development counterpart had stopped responding which when restarted along with HANA DB eliminated these errors. I am still not sure of the association between the Prod and Dev ECC which can lead to such SM21 errors in Prod but the errors have stopped now. Thanks for your responses, appreciate your support.

[bryan_bingay]

A couple of things stand out. HANA revision is very low, latest is maintenance revision 122.35. Lots of fixes since 122.13. The OS and service pack seems to be supported, but very old, see note 2235581. Here are some more questions for you.

1. Why do you think the messages you see in SM21 are from the secondary and are related to system replication?

2. Are you able to update HANA to the latest HANA 12 revision, 122.35?

3. Can you patch the OS with all the latest updates? The kernel version is from 2014.

4. Have you made all the OS changes outlined in SAP note 1954788?

5. Is this a playground system or a real system part of your prod landscape?

6. Have you installed the latest HANA client on all systems connecting to the HANA DB?

7. What hardware is this installed on? Not all hardware is supported. For more information, see the Certified and Supported SAP HANA® Hardware Directory and SAP Note 1943937 Hardware Configuration Check Tool - Central Note.

8. Do you use a DR provider for HA failover and virtual IP?

[avijish]

Hi Bryan,

Thanks for your response, I agree with you on the HANA maintenance revision being old. we will be patching this shortly to the latest version along with the latest OS (Suse 15 SP2). Further answers to your queries

1) A the start of the error log I get message Failed to initialize connection to <Secondary Hostname>/SQL Statement

2) Yes this is planned in next few weeks

3) Yes this is planned in next few weeks

4) Will analyse this and update here

5) Production system

6) Client version needs to be updated as well (current client version 1.00.097.00 Build 1434028111-1530)

7) Hardware is supported, will have to check the HWCCT tool outputs again

😎 No there is no DR provider for HA failover and virtual IP, HANA System replication is the DR.

From above points I can assume the issue might be fixed in a more recent HANA/OS/Client update/patch.

Thanks,

Vijish AN

[bryan_bingay]

Hi Vijish, do you have HANA Cockpit or HANA Studio to see the health of System Replication? What is the revison of HANA SPS12, OS version and SP, replication mode and operationmode? Is this a 2 node system, scaleup or scaleout? The the HANA administation guide and the FAQ linked below may help.

SAP HANA Administration Guide

1999880 - FAQ: SAP HANA System Replication

[avijish]

Hi Bryan, thanks for your response

See below details

replication mode is SYNCMEM

operation mode: delta_datashipping

This is a two node setup with Primary and Secondary HANA systems configured for System replication with above modes (No scale out)

Thanks