SAP HANA System Replication Scale-Up - Cost Optimized Scenario #

With the SAPHanaSR resource agent software package, we limit the support to Scale-Up (single-box to single-box) system replication with the following configurations and parameters:

Important

Without a valid STONITH method, the complete cluster is unsupported and will not work properly.

If you need to implement a different scenario, we strongly recommend to define a Proof of Concept (PoC) with SUSE. This PoC will focus on testing the existing solution in your scenario. Most of the above mentioned limitations are set because careful testing is needed.

In addition to SAP HANA, you need to install the SAP Host Agent on your system.

For information on supported hardware and virtualization, refer to the SUSE release notes and hardware compatibility database: * https://www.suse.com/releasenotes/ * https://www.suse.com/yessearch/

Also, take a look at the SAP HANA product availability matrix, which can for example be found at https://support.sap.com/en/release-upgrade-maintenance.html#section_1969201630

Additional information for deploying the cost optimized scenario in particular public clouds is available either from the respective cloud provider or at SUSE: https://documentation.suse.com/sbp/sap/

This document describes how to set up the cluster to control SAP HANA in System Replication scenarios. The document focuses on the steps to integrate an already installed and working SAP HANA with System Replication.

The described example setup builds an SAP HANA HA cluster in two data centers in Walldorf (WDF) and in Rot (ROT), installed on two SLES for SAP 12 SP4 systems. In addition, a non-replicated SAP HANA is installed and added to the cluster control.

Figure 8: Cluster with SAP HANA SR - cost optimized #

 

You can either set up the cluster using the YaST wizard, doing it manually or using your own automation.

If you prefer to use the YaST wizard, you can use the shortcut yast sap_ha to start the module. The procedure to set up SAPHanaSR using YaST is described in the product documentation of SUSE Linux Enterprise Server for SAP Applications in section Setting Up an SAP HANA Cluster at https://documentation.suse.com/sles-sap/12-SP4/single-html/SLES4SAP-guide/#cha-s4s-cluster.

Figure 9: Scenario Selection for SAP HANA in the YaST Module sap_ha #

 

This guide focuses on the manual setup of the cluster to explain the details and to give you the possibility to create your own automation.

The seven main setup steps are:

Planning the installation is essential for a successful SAP HANA cluster setup.

Before you start, you need the following:

4.1 Minimum Lab Requirements and Prerequisites #

 

Note

The minimum lab requirements mentioned here are by no means SAP sizing information. These data are provided only to rebuild the described cluster in a lab for test purposes. The following minimum setup uses the half-size of RAM for the secondary SAP HANA database which has table preload inactive. Even for tests the requirements can increase, depending on your test scenario. For productive systems ask your hardware vendor or use the official SAP sizing tools and services. Refer to the SAP HANA TDI documentation for allowed storage configuration and file systems.

Requirements with 1 SAP system replication instance per site (1 : 1) - without a majority maker (2 node cluster):

• 1 VM with 32GB RAM, 50 GB disk space for the system

• 1 VM with 48GB RAM, 50 GB disk space for the system

• 1 shared disk for SBD with 10 MB disk space

• 2 data disks (one per site) with a capacity of each 96 GB for SAP HANA

• 1 data disk (for the non-replicated database) with a capacity of 96 GB for SAP HANA

• 1 additional IP address for takeover

• 1 additional IP address for non-replicated database

• 1 optional IP address for HAWK Administration GUI

Requirements with 1 SAP system replication instance per site (1 : 1) - with a majority maker (3 node cluster):

• 1 VM with 32 GB RAM, 50 GB disk space for the system

• 1 VM with 48 GB RAM, 50 GB disk space for the system

• 1 VM with 2 GB RAM, 50 GB disk space for the system

• 2 data disks (one per site) with a capacity of each 96 GB for SAP HANA

• 1 data disk (for the non-replicated database) with a capacity of 96 GB for SAP HANA

• 1 additional IP address for takeover

• 1 additional IP address for non-replicated database

• 1 optional IP address for HAWK Administration GUI

This section contains information you should consider during the installation of the operating system.

For the scope of this document, first SUSE Linux Enterprise Server for SAP Applications is installed and configured. Then the SAP HANA database including the system replication is set up. Finally the automation with the cluster is set up and configured.

Even though this document focuses on the integration of an installed SAP HANA with system replication already set up into the pacemaker cluster, this chapter summarizes the test environment. Always use the official documentation from SAP to install SAP HANA and to set up the system replication.

suse02:~> HDB info
USER           PID  ...  COMMAND
ha1adm         6561 ...  -csh
ha1adm         6635 ...    \_ /bin/sh /usr/sap/HA1/HDB10/HDB info
ha1adm         6658 ...        \_ ps fx -U ha1 -o user,pid,ppid,pcpu,vsz,rss,args
ha1adm         5442 ...  sapstart pf=/hana/shared/HA1/profile/HA1_HDB10_suse02
ha1adm         5456 ...   \_ /usr/sap/HA1/HDB10/suse02/trace/hdb.sapHA1_HDB10 -d
-nw -f /usr/sap/HA1/HDB10/suse
ha1adm         5482 ...       \_ hdbnameserver
ha1adm         5551 ...       \_ hdbpreprocessor
ha1adm         5554 ...       \_ hdbcompileserver
ha1adm         5583 ...       \_ hdbindexserver
ha1adm         5586 ...       \_ hdbstatisticsserver
ha1adm         5589 ...       \_ hdbxsengine
ha1adm         5944 ...       \_ sapwebdisp_hdb
pf=/usr/sap/HA1/HDB10/suse02/wdisp/sapwebdisp.pfl -f /usr/sap/SL
ha1adm         5363 ...  /usr/sap/HA1/HDB10/exe/sapstartsrv
pf=/hana/shared/HA1/profile/HA1_HDB10_suse02 -D -u s

[memorymanager]
global_allocation_limit = <size_in_mb_for_non_replicated_hana>

For more information read the section Setting Up System Replication of the SAP HANA Administration Guide.

Procedure

7.1 Backing Up the Primary Database #

 

Back up the primary database as described in the SAP HANA Administration Guide, section SAP HANA Database Backup and Recovery. We provide an example with SQL commands. You need to adapt these backup commands to match your backup infrastructure.

Example 3: Simple backup for the system database and all tenants with one single backup call #

 

As user <sid>adm enter the following command:

hdbsql -u SYSTEM -d SYSTEMDB \
   "BACKUP DATA FOR FULL SYSTEM USING FILE ('backup')"

You will get a command output similar to the following:

0 rows affected (overall time 15.352069 sec; server time 15.347745 sec)

Example 4: Simple backup for a single container (non MDC) database #

 

Enter the following command as user <sid>adm:

hdbsql -i <instanceNumber> -u <dbuser> \
   "BACKUP DATA USING FILE ('backup')"

Important

Without a valid backup, you cannot bring SAP HANA into a system replication configuration.

7.2 Enable Primary Node #

 

As Linux user <sid>adm enable the system replication at the primary node. You need to define a site name (like WDF). This site name must be unique for all SAP HANA databases which are connected via system replication. This means the secondary must have a different site name.

Note

Do not use strings like "primary" and "secondary" as site names.

Example 5: Enable the Primary #

 

Enable the primary using the -sr_enable option.

suse01:~> hdbnsutil -sr_enable --name=WDF
checking local nameserver:
checking for active nameserver ...
nameserver is running, proceeding ...
configuring ini files ...
successfully enabled system as primary site ...
done.

Example 6: Check SR Configuration on the Primary #

 

Check the primary using the command hdbnsutil -sr_stateConfiguration.

suse01:~> hdbnsutil -sr_stateConfiguration --sapcontrol=1
SAPCONTROL-OK: <begin>
mode=primary
site id=1
site name=WDF
SAPCONTROL-OK: <end>
done.

The mode has changed from “none” to “primary”. The site now has a site name and a site ID.

suse02:~> HDB stop

cd /usr/sap/<SID>/SYS/global/security/rsecssfs
rsync -va {<node1-site A>:,}$PWD/data/SSFS_<SID>.DAT
rsync -va {<node1-site A>:,}$PWD/key/SSFS_<SID>.KEY

...
suse02:~> hdbnsutil -sr_register --name=ROT \
     --remoteHost=suse01 --remoteInstance=10 \
     --replicationMode=sync --operationMode=logreplay
adding site ...
checking for inactive nameserver ...
nameserver suse02:30001 not responding.
collecting information ...
updating local ini files ...
done.

[memorymanager]
global_allocation_limit = <size_in_mb_for_secondary_hana>

[system_replication]
preload_column_tables = false

suse02:~> HDB start
...
suse02:~> hdbnsutil -sr_stateConfiguration --sapcontrol=1
SAPCONTROL-OK: <begin>
mode=sync
site id=2
site name=ROT
active primary site=1
primary masters=suse01
SAPCONTROL-OK: <end>
done.

suse01:~> HDBSettings.sh systemReplicationStatus.py --sapcontrol=1
...
site/2/SITE_NAME=ROT
site/2/SOURCE_SITE_ID=1
site/2/REPLICATION_MODE=SYNC
site/2/REPLICATION_STATUS=ACTIVE
site/1/REPLICATION_MODE=PRIMARY
site/1/SITE_NAME=WDF
local_site_id=1
...

This step is mandatory to inform the cluster immediately if the secondary gets out of sync. The hook is called by SAP HANA using the HA/DR provider interface in point-of-time when the secondary gets out of sync. This is typically the case when the first commit pending is released. The hook is called by SAP HANA again when the system replication is back.

Procedure

Implement two SAP HANA HA/DR provider hooks. One hook is named SAPHanaSR and shipped with the SAPHanaSR package. The other is named srCostOptMemConfig and needs to be adapted to your database according to your specific username/password and connection.

The steps in this section must be performed on both sites. SAP HANA must be stopped to change the global.ini and allow SAP HANA to integrate the HA/DR hook script during start.

~> sapcontrol -nr <instanceNumber> -function StopSystem

[ha_dr_provider_SAPHanaSR]
provider = SAPHanaSR
path = /usr/share/SAPHanaSR/
execution_order = 1

[trace]
ha_dr_saphanasr = info

[system_replication]
operation_mode = logreplay

# SAPHanaSR-ScaleUp entries for writing srHook cluster attribute
<sid>adm ALL=(ALL) NOPASSWD: /usr/sbin/crm_attribute -n hana_<sid>_site_srHook_*

# SAPHanaSR-ScaleUp entries for writing srHook cluster attribute
Cmnd_Alias SOK_SITEA   = /usr/sbin/crm_attribute -n hana_<sid>_site_srHook_<siteA> -v SOK   -t crm_config -s SAPHanaSR
Cmnd_Alias SFAIL_SITEA = /usr/sbin/crm_attribute -n hana_<sid>_site_srHook_<siteA> -v SFAIL -t crm_config -s SAPHanaSR
Cmnd_Alias SOK_SITEB   = /usr/sbin/crm_attribute -n hana_<sid>_site_srHook_<siteB> -v SOK   -t crm_config -s SAPHanaSR
Cmnd_Alias SFAIL_SITEB = /usr/sbin/crm_attribute -n hana_<sid>_site_srHook_<siteB> -v SFAIL -t crm_config -s SAPHanaSR
<sid>adm ALL=(ALL) NOPASSWD: SOK_SITEA, SFAIL_SITEA, SOK_SITEB, SFAIL_SITEB

# cd /hana/shared/srHook
## copy the example from the appendix of this document
## set restricted file permissions
# chown <sid>adm.users srCostOptMemConfig.py
# chmod 500 srCostOptMemConfig.py

## change the connection setting to your local environment
# vi srCostOptMemConfig.py
dbuser="SYSTEM"
dbpwd="<yourPassword>"
dbinst="<yourInstanceNr>"
dbport="30013"

# cd /hana/shared/srHook
# ln -s /hana/shared/<SID>/exe/linuxx86_64/hdb/python_support/hdbcli/dbapi.py .
# ln -s /hana/shared/<SID>/exe/linuxx86_64/hdb/python_support/hdbcli/__init__.py .
# ln -s /hana/shared/<SID>/exe/linuxx86_64/hdb/python_support/hdbcli/resultrow.py .

[ha_dr_provider_srCostOptMemConfig]
provider = srCostOptMemConfig
path = /hana/shared/srHook/
execution_order = 2

[trace]
ha_dr_saphanasr = info

suse02 > cdtrace
suse02 > grep  srCostOptMemConfig nameserver_*.trc

This chapter describes the configuration of the cluster software SUSE Linux Enterprise High Availability Extension, which is part of SUSE Linux Enterprise Server for SAP Applications, and the SAP HANA Database integration.

9.1 Basic Cluster Configuration #

 

The first step is to set up the basic cluster framework. For convenience, use YaST2 or the ha-cluster-init script. It is strongly recommended to add a second corosync ring, change it to UCAST communication and adjust the timeout values to fit your environment.

9.1.1 Set up Watchdog for "Storage-Based Fencing" #

 

If you use the storage-based fencing (SBD) mechanism (diskless or disk-based), you must also configure a watchdog. The watchdog is needed to reset a node if the system cannot longer access the SBD (diskless or disk-based). It is mandatory to configure the Linux system for loading a watchdog driver. It is strongly recommended to use a watchdog with hardware assistance (as is available on most modern systems), such as hpwdt, iTCO_wdt, or others. As fallback, you can use the softdog module.

Example 20: Setup for Watchdog #

 

Important

Access to the watchdog timer: No other software must access the watchdog timer; it can only be accessed by one process at any time. Some hardware vendors ship systems management software that use the watchdog for system resets (for example HP ASR daemon). Such software must be disabled if the watchdog is to be used by SBD.

Determine the right watchdog module. Alternatively, you can find a list of installed drivers with your kernel version.

ls -l /lib/modules/$(uname -r)/kernel/drivers/watchdog

Check if any watchdog module is already loaded.

lsmod | egrep "(wd|dog|i6|iT|ibm)"

If you get a result, the system has already a loaded watchdog. If the watchdog does not match your watchdog device, you need to unload the module.

To safely unload the module, check first if an application is using the watchdog device.

lsof /dev/watchdog
rmmod <wrong_module>

Enable your watchdog module and make it persistent. For the example below, softdog has been used. However, softdog has some restrictions and should not be used as first option.

echo softdog > /etc/modules-load.d/watchdog.conf
systemctl restart systemd-modules-load

Check if the watchdog module is loaded correctly.

lsmod | grep dog
ls -l /dev/watchdog

Testing the watchdog can be done with a simple action. Ensure to switch of your SAP HANA first because the watchdog will force an unclean reset or shutdown of your system.

In case a hardware watchdog is used, a desired action is predefined after the timeout of the watchdog has reached. If your watchdog module is loaded and not controlled by any other application, do the following:

Important

Triggering the watchdog without continuously updating the watchdog resets/switches off the system. This is the intended mechanism. The following commands will force your system to be reset/switched off.

In case the softdog module is used, the following action can be performed:

sync; cat /dev/watchdog & while date; do sleep 10; done

After your test was successful, you must implement the watchdog on all cluster members.

9.1.2 Initial Cluster Setup Using ha-cluster-init #

 

For more detailed information about setting up a cluster, refer to the sections Setting Up the First Node and Adding the Second Node of the Installation and Setup Quick Start for SUSE Linux Enterprise High Availability Extension 12.

Create an initial setup, using the ha-cluster-init command, and follow the dialogs. Do this only on the first cluster node.

suse01:~> ha-cluster-init -u -s <sbddevice>

This command configures the basic cluster framework including:

• SSH keys

• csync2 to transfer configuration files

• SBD (at least one device)

• corosync (at least one ring)

• HAWK Web interface

Important

As requested by ha-cluster-init, change the password of the user hacluster.

9.1.3 Adapting the Corosync and SBD Configuration #

 

It is recommended to add a second corosync ring. If you did not start ha-cluster-init with the -u option, you need to change corosync to use UCAST communication. To change to UCAST, stop the already running cluster by using systemctl stop pacemaker. After the setup of the corosync configuration and the SBD parameters, start the cluster again.

9.1.3.1 Corosync Configuration #

 

Check the following blocks in the file /etc/corosync/corosync.conf. See also the example at the end of this document.

totem {
    ...

    interface {
        ringnumber: 0
        mcastport:  5405
        ttl:        1
    }
    #Transport protocol
    transport:      udpu

}
nodelist {
        node {
            ring0_addr:     192.168.1.11
            nodeid: 1
        }
        node {
            ring0_addr:     192.168.1.12
            nodeid: 2
        }
    }

9.1.3.2 Adapting the SBD Configuration #

 

You can skip this section if you do not have any SBD devices, but be sure to implement another supported fencing mechanism.

See the man pages sbd(8) and stonith_sbd(7) for details.

Table 3: SBD Options #

 

Parameter	Description
SBD_WATCHDOG="yes"	Use watchdog. It is mandatory to use a watchdog. SBD does not work reliable without watchdog. Refer to the SLES manual and SUSE TIDs 7016880 for setting up a watchdog.
SBD_STARTMODE="clean"	Start mode. If set to one, sbd will only start if the node was previously shut down cleanly or if the slot is empty.
SBD_PACEMAKER="yes"	Check Pacemaker quorum and node health.

In the following example, replace /dev/disk/by-id/SBDA and /dev/disk/by-id/SBDB by your real SBD device names.

# /etc/sysconfig/sbd
SBD_DEVICE="/dev/disk/by-id/SBDA;/dev/disk/by-id/SBDB"
SBD_WATCHDOG_DEV="/dev/watchdog"
SBD_PACEMAKER="yes"
SBD_STARTMODE="clean"
SBD_OPTS=""

In your specific system, the file might have additional parameters not discussed here.

9.1.3.3 Verifying the SBD Device #

 

You can skip this section if you do not have any SBD devices, but make sure to implement a supported fencing mechanism.

It is a good practice to check if the SBD device can be accessed from both nodes and does contain valid records. Check this for all devices configured in /etc/sysconfig/sbd. You can do so, for example, by calling cs_show_sbd_devices.

suse01:~ # sbd -d /dev/disk/by-id/SBDA dump
==Dumping header on disk /dev/disk/by-id/SBDA
Header version     : 2.1
UUID               : 0f4ea13e-fab8-4147-b9b2-3cdcfff07f86
Number of slots    : 255
Sector size        : 512
Timeout (watchdog) : 20
Timeout (allocate) : 2
Timeout (loop)     : 1
Timeout (msgwait)  : 40
==Header on disk /dev/disk/by-id/SBDA is dumped

The timeout values in our example are only start values. They need to be tuned to your environment.

To check the current SBD entries for the various cluster nodes, you can use sbd list. If all entries are clear, no fencing task is marked in the SBD device.

suse01:~ # sbd -d /dev/disk/by-id/SBDA list
0     suse01      clear

For more information on SBD configuration parameters, read the section Using SBD as Fencing Mechanism of the Installation and Setup Quick Start for SUSE Linux Enterprise High Availability Extension 12, and the TIDs 7016880 and 7008216.

Now it is time to restart the cluster at the first node again (systemctl start pacemaker).

9.1.4 Cluster Configuration on the Second Node #

 

The second node of the two nodes cluster can be integrated by starting the command ha-cluster-join. This command asks for the IP address or name of the first cluster node. With this command, all needed configuration files are copied over. As a result, the cluster is started on both nodes.

# ha-cluster-join -c <host1>

9.1.5 Checking the Cluster for the First Time #

 

Now it is time to check and optionally start the cluster for the first time on both nodes.

suse01:~ # systemctl status pacemaker
suse01:~ # systemctl status sbd
suse02:~ # systemctl status pacemaker
suse02:~ # systemctl status sbd
suse01:~ # systemctl start pacemaker
suse02:~ # systemctl start pacemaker

Check the cluster status. First, check if all nodes have used the SBD devices. To check the current SBD entries for the various cluster nodes, you can use sbd list. If all entries are clear , no fencing task is marked in the SBD device.

 suse01:~ # sbd -d /dev/disk/by-id/SBDA list
 0     suse01      clear
 1     suse02      clear

You can also call cs_show_sbd_devices again. Next, check if all nodes have joined the cluster. To do so, call crm_mon. Use the option "-r" to also see the resources that are configured but stopped.

# crm_mon -r

The command will show the "empty" cluster and will print something similar to the screen output below. The most interesting information for now is that there are two nodes in the status "online", and the message "partition with quorum".

Stack: corosync
Current DC: suse01 (version 1.1.19+20180928.0d2680780-1.8-1.1.19+20180928.0d2680780) - partition with quorum
Last updated: Fri Nov 29 12:41:16 2019
Last change: Fri Nov 29 12:40:22 2019 by root via crm_attribute on suse02
2 nodes configured
1 resource configured
Online: [ suse01 suse02 ]
Full list of resources:
 stonith-sbd    (stonith:external/sbd): Started suse01

suse01:~ # vi crm-fileXX
suse01:~ # crm configure load update crm-fileXX

suse01:~ # vi crm-bs.txt
# enter the following to crm-bs.txt
property $id="cib-bootstrap-options" \
              stonith-enabled="true" \
              stonith-action="reboot" \
              stonith-timeout="150s"
rsc_defaults $id="rsc-options" \
              resource-stickiness="1000" \
              migration-threshold="3"
op_defaults $id="op-options" \
                 timeout="600"

suse01:~ # crm configure load update crm-bs.txt

# vi crm-sbd.txt
# enter the following to crm-sbd.txt
primitive stonith-sbd stonith:external/sbd \
    params pcmk_delay_max="30"

suse01:~ # crm configure load update crm-sbd.txt

# vi crm-saphanatop.txt
# enter the following to crm-saphanatop.txt
primitive rsc_SAPHanaTopology_HA1_HDB10 ocf:suse:SAPHanaTopology \
        op monitor interval="10" timeout="600" \
        op start interval="0" timeout="600" \
        op stop interval="0" timeout="300" \
        params SID="HA1" InstanceNumber="10"
clone cln_SAPHanaTopology_HA1_HDB10 rsc_SAPHanaTopology_HA1_HDB10 \
        meta clone-node-max="1" interleave="true"

suse01:~ # crm configure load update crm-saphanatop.txt

# vi crm-saphana.txt
# enter the following to crm-saphana.txt
primitive rsc_SAPHana_HA1_HDB10 ocf:suse:SAPHana \
        op start interval="0" timeout="3600" \
        op stop interval="0" timeout="3600" \
        op promote interval="0" timeout="3600" \
        op monitor interval="60" role="Master" timeout="700" \
        op monitor interval="61" role="Slave" timeout="700" \
        params SID="HA1" InstanceNumber="10" PREFER_SITE_TAKEOVER="false" \
        DUPLICATE_PRIMARY_TIMEOUT="7200" AUTOMATED_REGISTER="false"
ms msl_SAPHana_HA1_HDB10 rsc_SAPHana_HA1_HDB10 \
        meta clone-max="2" clone-node-max="1" interleave="true"

suse01:~ # crm configure load update crm-saphana.txt

# vi crm-vip.txt
# enter the following to crm-vip.txt

primitive rsc_ip_HA1_HDB10 ocf:heartbeat:IPaddr2 \
        op monitor interval="10s" timeout="20s" \
        params ip="192.168.1.20"

suse01:~ # crm configure load update crm-vip.txt

# vi crm-cs.txt
# enter the following to crm-cs.txt
colocation col_saphana_ip_HA1_HDB10 2000: rsc_ip_HA1_HDB10:Started \
    msl_SAPHana_HA1_HDB10:Master
order ord_SAPHana_HA1_HDB10 Optional: cln_SAPHanaTopology_HA1_HDB10 \
    msl_SAPHana_HA1_HDB10

suse01:~ # crm configure load update crm-cs.txt

# vi crm-si.txt
# enter the following to crm-si.txt
primitive rsc_SAP_QAS_HDB20 ocf:heartbeat:SAPInstance \
  params InstanceName="QAS_HDB20_suse02" \
        MONITOR_SERVICES="hdbindexserver|hdbnameserver" \
        START_PROFILE="/usr/sap/QAS/SYS/profile/QAS_HDB20_suse02" \
  op start interval="0" timeout="600" \
  op monitor interval="120" timeout="700" \
  op stop interval="0" timeout="300" \
  meta priority="100"

suse01:~ # crm configure load update crm-si.txt

# vi crm-con.txt
# enter the following to crm-con.txt
location loc_QAS_never_on_suse01 rsc_SAP_QAS_HDB20 -inf: suse01
colocation col_QAS_never_with_HA1ip -inf: rsc_SAP_QAS_HDB20:Started \
  rsc_ip_HA1_HDB10
order ord_QASstop_before_HA1-promote mandatory: rsc_SAP_QAS_HDB20:stop \
  msl_SAPHana_HA1_HDB10:promote

suse01:~ # crm configure load update crm-con.txt

The lists of tests will be further enhanced with a next update of this document.

For any cluster setup testing is crucial. Make sure that all test cases derived from your organizations or from customer expectations are fully implemented and successfully passed. Otherwise the project is likely to fail in production.

If not described differently, the test prerequisite is always that both nodes are booted, normal members of the cluster and that the HANA RDBMS is running. There are no left-over migration constraints or resource failures contained in the cluster information base (CIB). The system replication is in sync (SOK).

This can be checked, for example, with the following command sequence:

 # crm_mon -1r
 # crm configure show | grep cli-
 # SAPHanaSR-showAttr
 # cs_clusterstate -i

See also the manual pages SAPHanaSR-showAttr(8), crm_mon(8), crm(8), cs_clusterstate(8), SAPHanaSR_maintenance_examples(7).

10.1 Test Cases for Semi-Automation #

 

For the following test descriptions, we assume the following parameter values: * PREFER_SITE_TAKEOVER="false" * AUTOMATED_REGISTER="false".

Note

The following tests are designed to run in a sequence. Each test depends on the exit state of the preceding tests.

10.1.1 Tests for Primary Database or Node #

 

10.1.1.1 Test: Stop Primary Database on Site A (Node 1) #

 

Example 21: Test STOP_PRIMARY_DB_SITE_A_SEMI #

 

Component: #

 

• Primary Database

Description: #

 

• Stop Primary on site A (node 1)

Test Procedure: #

 

1. Stop the SAP HANA database as user <sid>adm

   suse01# HDB stop

Expected: #

 

• Primary restarts on site A (PREFER_SITE_TAKEOVER=false) until failcount >= migration-threshold

• If takeover occurs:

  • non-replicated database is stopped on node 2 (site B)

  • Secondary database is promoted as primary

Recovery Procedure: #

 

• No recovery needed, if no takeover did occur

• Recovery after takeover:

  1. Register site A to site B

  2. Resource cleanup for site A

10.1.1.2 Test: Stop Primary Database on Site B (Node 2) #

 

Example 22: Test STOP_PRIMARY_DB_SITE_B_SEMI #

 

Component: #

 

• Primary Database

Description: #

 

• Stop Primary on site B (node 2)

Test Procedure: #

 

1. Stop the SAP HANA database as user <sid>adm

   suse01# HDB stop

Expected: #

 

• Primary restarts on site B (PREFER_SITE_TAKEOVER=false) until failcount >= migration-threshold

• Non-replicated database still stopped on node 2 (site B)

• If takeover occurs:

  • Secondary database is promoted as primary

  • non-replicated database is started on node 2 (site B)

Recovery Procedure: #

 

• No recovery needed if no takeover did occur

• Recovery after takeover:

  1. Register site B to site A

  2. Resource cleanup for site B

10.1.1.3 Test: Crash Primary Database on Site A (Node 1) #

 

Example 23: Test CRASH_PRIMARY_DB_SITE_A_SEMI #

 

Component: #

 

• Primary Database

Description: #

 

• Kill Primary on site A (node 1)

Test Procedure: #

 

1. Kill (send signal to) the SAP HANA database as user <sid>adm

   suse01# HDB kill-9

Expected: #

 

• Primary restarts on site A (PREFER_SITE_TAKEOVER=false) until failcount >= migration-threshold

• If takeover occurs:

  • Non-replicated database is stopped on node 2 (site B)

  • Secondary database is promoted as primary

Recovery Procedure: #

 

• No recovery needed if no takeover did occur

• Recovery after takeover:

  1. Register site A to site B

  2. Resource cleanup for site A

10.1.1.4 Test: Crash Primary Database on Site B (Node 2) #

 

Example 24: Test CRASH_PRIMARY_DB_SITE_B_SEMI #

 

Component: #

 

• Primary Database

Description: #

 

• Kill Primary on site B (node 2)

Test Procedure: #

 

1. Kill Primary on site B (node 2) as user <sid>adm

   suse02# HDB kill-9

Expected: #

 

• Primary restarts on site B (PREFER_SITE_TAKEOVER=false) until failcount >= migration-threshold

• Non-replicated database still stopped on node 2 (site B)

Recovery Procedure: #

 

• No recovery needed if no takeover did occur

• Recovery after takeover:

  1. Register site B to site A

  2. Resource cleanup for site B

10.1.1.5 Test: Crash Primary Node on Site A (Node 1) #

 

Example 25: Test CRASH_PRIMARY_NODE_SITE_A_SEMI #

 

Component: #

 

• Cluster Node

Description: #

 

• Crash node 1 (site A)

Test Procedure: #

 

1. Crash the node by proc-sysrq-trigger as user root

   suse01# sync; echo b > /proc/sysrq-trigger

Expected: #

 

• Non-replicated SAP HANA stopped on node 2

• Cluster takeover to site B

• Non-replicated database is stopped on node 2 (site B)

• Secondary database is promoted as primary

Recovery Procedure: #

 

• Recovery after takeover:

  1. Optionally clean up sbd slot for node 1

  2. Start cluster framework on node 1

  3. Wait until node 1 joins the cluster

  4. Register site A to site B

10.1.1.6 Test: Crash Primary Node on Site B (Node 2) #

 

Example 26: Test CRASH_PRIMARY_NODE_SITE_B_SEMI #

 

Component: #

 

• Cluster Node

Description: #

 

• Crash node 2 (site B)

Test Procedure: #

 

1. Crash the node by proc-sysrq-trigger as user root

   suse02# sync; echo b > /proc/sysrq-trigger

Expected: #

 

• Cluster takeover to site A

• Non-replicated database not available (no takeover to site A)

Recovery Procedure: #

 

• Recovery after takeover:

  1. Optionally clean up sbd slot for node 2

  2. Start cluster framework on node 2

  3. Wait until node 2 joins the cluster

  4. Register site B to site A

10.1.2 Tests for Secondary Database or Node #

 

10.1.2.1 Test: Stop the Secondary Database on Site B (Node 2) #

 

Example 27: Test STOP_SECONDARY_DB_SITE_B_SEMI #

 

Component: #

 

• Secondary Database

Description: #

 

• Stop secondary database on node 2 (site B)

Test Procedure: #

 

1. Stop the secondary SAP HANA database as user <sid>adm

   suse02# HDB stop

Expected: #

 

• Cluster restarts Secondary on node 2 (site B)

• non-replicated database not affected on node 2 (site B)

Recovery Procedure: #

 

1. Wait and see

2. Resource cleanup for site B

10.1.2.2 Test: Crash the Secondary Database on Site B (Node 2) #

 

Example 28: Test CRASH_SECONDARY_DB_SITE_B_SEMI #

 

Component: #

 

• Secondary Database

Description: #

 

• Crash secondary database on node 2 (site B)

Test Procedure: #

 

1. Kill (send signal to) the secondary SAP HANA database as user <sid>adm

   suse02# HDB kill-9

Expected: #

 

• Cluster restarts Secondary on node 2 (site B)

• Non-replicated database not affected on node 2 (site B)

Recovery Procedure: #

 

1. Wait and see

2. Resource cleanup for site B

10.1.2.3 Test: Crash the Secondary Node on Site B (Node2) #

 

Example 29: Test CRASH_SECONDARY_NODE_SITE_B_SEMI #

 

Component: #

 

• Cluster Node

Description: #

 

• Crash node 2 (site B)

Test Procedure: #

 

1. Crash the node by proc-sysrq-trigger as user root

   suse02# sync; echo b > /proc/sysrq-trigger

Expected: #

 

• No takeover of node 2 resources to site A

• Non-replicated database not available (no takeover to site A)

Recovery Procedure: #

 

• Recovery after node 2 is back:

  1. Optionally clean up sbd slot for node 2

  2. Start cluster framework on node 2

  3. Wait until node 2 joins the cluster

10.1.3 Tests for Non-Replicated Database #

 

10.1.3.1 Test: Stop Non-Replicated Database on SiteB (Node 2) #

 

Example 30: Test STOP_NONSR_DB_SITE_B_SEMI #

 

Component: #

 

• Non-Replicated Database

Description: #

 

• Stop non-replicated database node 2 (site B)

Test Procedure: #

 

1. Kill (send signal to) the secondary SAP HANA database as user <sid>adm

   suse02# HDB stop

Expected: #

 

• Cluster restarts non-replicated database on node 2 (site B)

• Secondary database is not affected

Recovery Procedure: #

 

1. Clean up non-replicated database resource

10.1.3.2 Test: Crash Non-Replicated Database on Site B (Node 2) #

 

Example 31: Test CRASH_NONSR_DB_SITE_B_SEMI #

 

Component: #

 

• Non-Replicated Database

Description: #

 

• Crash non-replicated database on node 2 (site B)

Test Procedure: #

 

1. Kill (send signal to) the non-replicated SAP HANA database as user <sid>adm

   suse02# HDB kill-9

Expected: #

 

• Cluster restarts non-replicated database on node 2 (site B)

• Secondary database is not affected

Recovery Procedure: #

 

1. Clean up non-replicated database resource

10.1.4 Tests for Other Components #

 

10.1.4.1 Test: Failure of Dedicated Replication LAN #

 

Example 32: Test FAIL_NETWORK_SR_SEMI #

 

Component: #

 

• Replication Network

Description: #

 

• Pull LAN port down or block network packets for system replication. Corosync network still available.

Expected: #

 

• System replication status fall down to status SFAIL

• Primary stays on node 1 (site A)

• No cluster takeover

• Non-replicated database not affected on node 2 (site B)

Recovery Procedure: #

 

1. Reestablish network connection

2. Wait until System replication status is SOK again

10.1.5 Test Maintenance Procedures #

 

Also test the maintenance procedures mentioned in section Section 11.3, “Maintenance”.

10.2 Test Cases for Full Automation #

 

For the following test descriptions, we assume the following parameter values: * PREFER_SITE_TAKEOVER="false" * AUTOMATED_REGISTER="true".

Note

The following tests are designed to run in a sequence. Each test depends on the exit state of the preceding tests.

10.2.1 Tests for Primary Database or Node #

 

10.2.1.1 Test: Stop Primary Database on Site A (Node 1) #

 

Example 33: Test STOP_PRIMARY_DB_SITE_A_FULL #

 

Component: #

 

• Primary Database

Description: #

 

• Stop primary database on site A (node 1)

Test Procedure: #

 

1. Stop the SAP HANA database as user <sid>adm

   suse01# HDB stop

Expected: #

 

• Primary restarts on site A (PREFER_SITE_TAKEOVER=false) until failcount >= migration-threshold

• If takeover occurs:

  • Non-replicated database is stopped on node 2 (site B)

  • Secondary database is promoted as primary

  • SiteA is automatically registered to SiteB

Recovery Procedure: #

 

• No recovery needed, if no takeover did occur

• Recovery after takeover:

  1. Resource cleanup for site A

10.2.1.2 Test: Stop Primary Database on Site B (Node 2) #

 

Example 34: Test STOP_PRIMARY_DB_SITE_B_FULL #

 

Component: #

 

• Primary Database

Description: #

 

• Stop primary database on site B (node 2)

Test Procedure: #

 

1. Stop the SAP HANA database as user <sid>adm

   suse01# HDB stop

Expected: #

 

• Primary restarts on site B (PREFER_SITE_TAKEOVER=false) until failcount >= migration-threshold

• Non-replicated database still stopped on node 2 (site B)

• If takeover occurs:

  • Secondary database is promoted as primary

  • non-replicated database is started on node 2 (site B)

  • SiteB is automatically registered to SiteA

Recovery Procedure: #

 

• No recovery needed if no takeover did occur

• Recovery after takeover:

  1. Resource cleanup for site B

10.2.1.3 Test: Crash Primary Database on Site A (Node 1) #

 

Example 35: Test CRASH_PRIMARY_DB_SITE_A_FULL #

 

Component: #

 

• Primary Database

Description: #

 

• Kill primary database on site A (node 1)

Test Procedure: #

 

1. Kill (send signal to) the SAP HANA database as user <sid>adm

   suse01# HDB kill-9

Expected: #

 

• Primary restarts on site A (PREFER_SITE_TAKEOVER=false) until failcount >= migration-threshold

• If takeover occurs:

  • Non-replicated database is stopped on node 2 (site B)

  • Secondary database is promoted as primary

  • SiteA is registered to SiteB

Recovery Procedure: #

 

• No recovery needed if no takeover did occur

• Recovery after takeover:

  1. Resource cleanup for site A

10.2.1.4 Test: Crash Primary Database on Site B (Node 2) #

 

Example 36: Test CRASH_PRIMARY_DB_SITE_B_FULL #

 

Component: #

 

• Primary Database

Description: #

 

• Kill primary database on site B (node 2)

Test Procedure: #

 

1. Kill primary database on site B (node 2) as user <sid>adm

   suse02# HDB kill-9

Expected: #

 

• Primary restarts on site B (PREFER_SITE_TAKEOVER=false) until failcount >= migration-threshold

• Non-replicated database still stopped on node 2 (site B)

• If takeover occurs:

  • Secondary database is promoted as primary

  • Non-replicated database is started on node 2 (site B)

  • SiteB is automatically registered to SiteA

Recovery Procedure: #

 

• No recovery needed if no takeover did occur

• Recovery after takeover:

  1. Resource cleanup for site B

10.2.1.5 Test: Crash Primary Node on Site A (Node 1) #

 

Example 37: Test CRASH_PRIMARY_NODE_SITE_A_FULL #

 

Component: #

 

• Cluster Node

Description: #

 

• Crash node 1 (site A)

Test Procedure: #

 

1. Crash the node by proc-sysrq-trigger as user root

   suse01# sync; echo b > /proc/sysrq-trigger

Expected: #

 

• Non-replicated SAP HANA stopped on node 2

• Cluster takeover to site B

• Non-replicated database is stopped on node 2 (site B)

• Secondary database is promoted as primary

• Later, when node 1 joins the cluster again:

  • SiteA is registered to SiteB

Recovery Procedure: #

 

• Recovery after takeover:

  1. Optionally clean up sbd slot for node 1

  2. Start cluster framework on node 1

  3. Wait until node 1 joins the cluster

10.2.1.6 Test: Crash Primary Node on Site B (Node 2) #

 

Example 38: Test CRASH_PRIMARY_NODE_SITE_B_FULL #

 

Component: #

 

• Cluster Node

Description: #

 

• Crash node 2 (site B) as user root

Test Procedure: #

 

1. Crash the node by proc-sysrq-trigger

   suse02# sync; echo b > /proc/sysrq-trigger

Expected: #

 

• Cluster takeover to site A

• Non-replicated database not available (no takeover to site A)

• Later, when node 2 joins the cluster again:

  • SiteB is registered to SiteA

  • Non-replicated database will be started

Recovery Procedure: #

 

• Recovery after takeover:

  1. Optionally clean up sbd slot for node 2

  2. Start cluster framework on node 2

  3. Wait until node 2 joins the cluster

10.2.2 Tests for Secondary Database or Node #

 

10.2.2.1 Test: Stop the Secondary Database on Site B (Node 2) #

 

Example 39: Test STOP_SECONDARY_DB_SITE_B_FULL #

 

Component: #

 

• Secondary Database

Description: #

 

• Stop secondary database on node 2 (site B)

Test Procedure: #

 

1. Stop the secondary SAP HANA database as user <sid>adm

   suse02# HDB stop

Expected: #

 

• Cluster restarts Secondary on node 2 (site B)

• Non-replicated database not affected on node 2 (site B)

Recovery Procedure: #

 

1. Wait and see

2. Resource cleanup for site B

10.2.2.2 Test: Crash the Secondary Database on Site B (Node 2) #

 

Example 40: Test CRASH_SECONDARY_DB_SITE_B_FULL #

 

Component: #

 

• Secondary Database

Description: #

 

• Crash secondary database on node 2 (site B)

Test Procedure: #

 

1. Kill (send signal to) the secondary SAP HANA database as user <sid>adm

   suse02# HDB kill-9

Expected: #

 

• Cluster restarts Secondary on node 2 (site B)

• Non-replicated database not affected on node 2 (site B)

Recovery Procedure: #

 

1. Wait and see

2. Resource cleanup for site B

10.2.2.3 Test: Crash the Secondary Node on Site B (Node2) #

 

Example 41: Test CRASH_SECONDARY_NODE_SITE_B_FULL #

 

Component: #

 

• Cluster Node

Description: #

 

• Crash node 2 (site B)

Test Procedure: #

 

1. Crash the node by proc-sysrq-trigger as user root

   suse02# sync; echo b > /proc/sysrq-trigger

Expected: #

 

• No takeover of node 2 resources to site A

• Non-replicated database not available (no takeover to site A)

Recovery Procedure: #

 

• Recovery after node 2 is back:

  1. Optionally clean up sbd slot for node 2

  2. Start cluster framework on node 2

  3. Wait until node 2 joins the cluster

10.2.3 Tests for Non-Replicated Database #

 

10.2.3.1 Test: Stop Non-Replicated Database on SiteB (Node 2) #

 

Example 42: Test STOP_NONSR_DB_SITE_B_FULL #

 

Component: #

 

• Non-Replicated Database

Description: #

 

• Stop non-replicated database node 2 (site B)

Test Procedure: #

 

1. Kill (send signal to) the secondary SAP HANA database as user <sid>adm

   suse02# HDB stop

Expected: #

 

• Cluster restarts non-replicated database on node 2 (site B)

• Secondary database is not affected

Recovery Procedure: #

 

1. Clean up non-replicated database resource

10.2.3.2 Test: Crash Non-Replicated Database on Site B (Node 2) #

 

Example 43: Test CRASH_NONSR_DB_SITE_B_FULL #

 

Component: #

 

• Non-Replicated Database

Description: #

 

• Crash non-replicated database on node 2 (site B)

Test Procedure: #

 

1. Kill (send signal to) the non-replicated SAP HANA database as user <sid>adm

   suse02# HDB kill-9

Expected: #

 

• Cluster restarts non-replicated database on node 2 (site B)

• Secondary database is not affected

Recovery Procedure: #

 

1. Clean up non-replicated database resource

10.2.4 Tests for Other Components #

 

10.2.4.1 Test: Failure of Dedicated Replication LAN #

 

Example 44: Test FAIL_NETWORK_SR_FULL #

 

Component: #

 

• Replication Network

Description: #

 

• Pull LAN port down or block network packets for system replication, Corosync network still available.

Expected: #

 

• System replication status fall down to status SFAIL

• Primary stays on node 1 (site A)

• No cluster takeover

• Non-replicated database not affected on node 2 (site B)

Recovery Procedure: #

 

1. Reestablish network connection

2. Wait until system replication status is SOK again

10.2.5 Test Maintenance Procedures #

 

Also, test the maintenance procedures mentioned in section Section 11.3, “Maintenance”.

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