Merge pull request #289593 from msftrobiro/sap-hana-chksrv-pacemaker-rhel

prmerger-automator[bot] · web-flow · commit 87846bd5728c · 2024-11-01T07:44:03.000Z
SAP: Add ChkSrv hook for HANA on RHEL pacemaker
diff --git a/articles/sap/workloads/disaster-recovery-sap-hana.md b/articles/sap/workloads/disaster-recovery-sap-hana.md
@@ -61,7 +61,7 @@ Requirements for additional HSR sites are different for HANA scale-up and HANA s
 
 ## HANA scale-up: Add HANA multitarget system replication for DR purposes
 
-With SAP HANA HA hooks SAPHanaSR/susHanaSR for [SLES](./sap-hana-high-availability.md#implement-hana-resource-agents) and [RHEL](./sap-hana-high-availability-rhel.md#implement-the-python-system-replication-hook-saphanasr), you can add additional sites to HANA system replication. The Pacemaker environment is aware of a HANA multitarget setup.
+With SAP HANA HA hooks SAPHanaSR/susHanaSR for [SLES](./sap-hana-high-availability.md#implement-hana-resource-agents) and [RHEL](./sap-hana-high-availability-rhel.md#implement-sap-hana-system-replication-hooks), you can add additional sites to HANA system replication. The Pacemaker environment is aware of a HANA multitarget setup.
 
 Failure of additional sites doesn't trigger any cluster action. The cluster detects the replication status of connected sites and the monitored attribute for the third site can change between `SOK` and `SFAIL` states. Any takeover tests to the additional site or executing your DR exercise process should first place the cluster resources into maintenance mode to prevent any undesired cluster action.
 
diff --git a/articles/sap/workloads/sap-hana-high-availability-netapp-files-red-hat.md b/articles/sap/workloads/sap-hana-high-availability-netapp-files-red-hat.md
@@ -419,7 +419,7 @@ Follow the steps in [Set up Pacemaker on Red Hat Enterprise Linux](./high-availa
 
 ### Implement the Python system replication hook SAPHanaSR
 
-This step is an important one to optimize the integration with the cluster and improve the detection when a cluster failover is needed. We highly recommend that you configure the SAPHanaSR Python hook. Follow the steps in [Implement the Python system replication hook SAPHanaSR](sap-hana-high-availability-rhel.md#implement-the-python-system-replication-hook-saphanasr).
+This step is an important one to optimize the integration with the cluster and improve the detection when a cluster failover is needed. We highly recommend that you configure the SAPHanaSR Python hook. Follow the steps in [Implement the Python system replication hook SAPHanaSR](sap-hana-high-availability-rhel.md#implement-sap-hana-system-replication-hooks).
 
 ### Configure file system resources
 
diff --git a/articles/sap/workloads/sap-hana-high-availability-rhel.md b/articles/sap/workloads/sap-hana-high-availability-rhel.md
@@ -217,44 +217,7 @@ The steps in this section use the following prefixes:
    * [2593824 - Linux: Running SAP applications compiled with GCC 7.x](https://launchpad.support.sap.com/#/notes/2593824)
    * [2886607 - Linux: Running SAP applications compiled with GCC 9.x](https://launchpad.support.sap.com/#/notes/2886607)
 
-1. **[A]** Install the SAP HANA.
-
-   To install SAP HANA System Replication, see [Automating SAP HANA Scale-Up System Replication using the RHEL HA Add-On](https://access.redhat.com/articles/3004101).
-
-   Run the **hdblcm** program from the HANA DVD. Enter the following values at the prompt:
-   1. Choose installation: Enter **1**.
-   1. Select additional components for installation: Enter **1**.
-   1. Enter **Installation Path** [/hana/shared]: Select Enter.
-   1. Enter **Local Host Name [..]**: Select Enter.
-   1. **Do you want to add additional hosts to the system? (y/n)** [n]: Select Enter.
-   1. Enter **SAP HANA System ID**: Enter the SID of HANA, for example: **HN1**.
-   1. Enter **Instance Number** [00]: Enter the HANA Instance number. Enter **03** if you used the Azure template or followed the manual deployment section of this article.
-   1. Select **Database Mode / Enter Index** [1]: Select Enter.
-   1. Select **System Usage / Enter Index** [4]: Select the system usage value.
-   1. Enter **Location of Data Volumes** [/hana/data]: Select Enter.
-   1. Enter **Location of Log Volumes** [/hana/log]: Select Enter.
-   1. **Restrict maximum memory allocation?** [n]: Select Enter.
-   1. Enter **Certificate Host Name For Host '...'** [...]: Select Enter.
-   1. Enter **SAP Host Agent User (sapadm) Password**: Enter the host agent user password.
-   1. Confirm **SAP Host Agent User (sapadm) Password**: Enter the host agent user password again to confirm.
-   1. Enter **System Administrator (hdbadm) Password**: Enter the system administrator password.
-   1. Confirm **System Administrator (hdbadm) Password**: Enter the system administrator password again to confirm.
-   1. Enter **System Administrator Home Directory** [/usr/sap/HN1/home]: Select Enter.
-   1. Enter **System Administrator Login Shell** [/bin/sh]: Select Enter.
-   1. Enter **System Administrator User ID** [1001]: Select Enter.
-   1. Enter **ID of User Group (sapsys)** [79]: Select Enter.
-   1. Enter **Database User (SYSTEM) Password**: Enter the database user password.
-   1. Confirm **Database User (SYSTEM) Password**: Enter the database user password again to confirm.
-   1. **Restart system after machine reboot?** [n]: Select Enter.
-   1. **Do you want to continue? (y/n)**: Validate the summary. Enter **y** to continue.
-
-1. **[A]** Upgrade the SAP Host Agent.
-
-   Download the latest SAP Host Agent archive from the [SAP Software Center][sap-swcenter] and run the following command to upgrade the agent. Replace the path to the archive to point to the file that you downloaded:
-
-   ```bash
-   sudo /usr/sap/hostctrl/exe/saphostexec -upgrade -archive <path to SAP Host Agent>;
-   ```
+1. **[A]** Install SAP HANA, following [SAP's documentation](https://help.sap.com/docs/SAP_HANA_PLATFORM/2c1988d620e04368aa4103bf26f17727/2d4de94c8bf14cda8d37278647fff8ab.html).
 
 1. **[A]** Configure the firewall.
 
@@ -285,8 +248,6 @@ The steps in this section use the following prefixes:
 
 1. **[1]** Create the tenant database.
 
-   If you're using SAP HANA 2.0 or MDC, create a tenant database for your SAP NetWeaver system. Replace **NW1** with the SID of your SAP system.
-
    Run the following command as <hanasid\>adm:
 
    ```bash
@@ -350,77 +311,6 @@ The steps in this section use the following prefixes:
    # site name: SITE1
    ```
 
-## Configure SAP HANA 1.0 System Replication
-
-The steps in this section use the following prefixes:
-
-* **[A]**: The step applies to all nodes.
-* **[1]**: The step applies to node 1 only.
-* **[2]**: The step applies to node 2 of the Pacemaker cluster only.
-
-1. **[A]** Configure the firewall.
-
-   Create firewall rules to allow HANA System Replication and client traffic. The required ports are listed on [TCP/IP Ports of All SAP Products](https://help.sap.com/viewer/ports). The following commands are just an example to allow HANA 2.0 System Replication. Adapt it to your SAP HANA 1.0 installation.
-
-   ```bash
-   sudo firewall-cmd --zone=public --add-port=40302/tcp --permanent
-   sudo firewall-cmd --zone=public --add-port=40302/tcp
-   ```
-
-1. **[1]** Create the required users.
-
-   Run the following command as root. Make sure to replace the values for HANA System ID (for example, **HN1**), instance number (**03**), and any usernames, with the values of your SAP HANA installation:
-
-   ```bash
-   PATH="$PATH:/usr/sap/HN1/HDB03/exe"
-   hdbsql -u system -i 03 'CREATE USER hdbhasync PASSWORD "passwd"'
-   hdbsql -u system -i 03 'GRANT DATA ADMIN TO hdbhasync'
-   hdbsql -u system -i 03 'ALTER USER hdbhasync DISABLE PASSWORD LIFETIME'
-   ```
-
-1. **[A]** Create the keystore entry.
-
-   Run the following command as root to create a new keystore entry:
-
-   ```bash
-   PATH="$PATH:/usr/sap/HN1/HDB03/exe"
-   hdbuserstore SET hdbhaloc localhost:30315 hdbhasync passwd
-   ```
-
-1. **[1]** Back up the database.
-
-   Back up the databases as root:
-
-   ```bash
-   PATH="$PATH:/usr/sap/HN1/HDB03/exe"
-   hdbsql -d SYSTEMDB -u system -i 03 "BACKUP DATA USING FILE ('initialbackup')"
-   ```
-
-   If you use a multitenant installation, also back up the tenant database:
-
-   ```bash
-   hdbsql -d HN1 -u system -i 03 "BACKUP DATA USING FILE ('initialbackup')"
-   ```
-
-1. **[1]** Configure system replication on the first node.
-
-   Create the primary site as <hanasid\>adm:
-
-   ```bash
-   su - hdbadm
-   hdbnsutil -sr_enable –-name=SITE1
-   ```
-
-1. **[2]** Configure system replication on the secondary node.
-
-   Register the secondary site as <hanasid\>adm:
-
-   ```bash
-   HDB stop
-   hdbnsutil -sr_register --remoteHost=hn1-db-0 --remoteInstance=03 --replicationMode=sync --name=SITE2
-   HDB start
-   ```
-
 ## Create a Pacemaker cluster
 
 Follow the steps in [Setting up Pacemaker on Red Hat Enterprise Linux in Azure](high-availability-guide-rhel-pacemaker.md) to create a basic Pacemaker cluster for this HANA server.
@@ -430,34 +320,23 @@ Follow the steps in [Setting up Pacemaker on Red Hat Enterprise Linux in Azure](
 >
 > When using HA solutions to manage SAP HANA system replication in combination with systemd-enabled SAP HANA instances (refer to SAP Note [3189534](https://me.sap.com/notes/3189534)), additional steps are necessary to ensure that the HA cluster can manage the SAP instance without systemd interference. So, for SAP HANA system integrated with systemd, additional steps outlined in [Red Hat KBA 7029705](https://access.redhat.com/solutions/7029705) must be followed on all cluster nodes.
 
-## Implement the Python system replication hook SAPHanaSR
+## Implement SAP HANA system replication hooks
 
-This important step optimizes the integration with the cluster and improves the detection when a cluster failover is needed. We highly recommend that you configure the SAPHanaSR Python hook.
+This important step optimizes the integration with the cluster and improves the detection when a cluster failover is needed. It is mandatory for correct cluster operation to enable the SAPHanaSR hook. We highly recommend that you configure both SAPHanaSR and ChkSrv Python hooks. 
 
-1. **[A]** Install the SAP HANA resource agents on **all nodes**. Make sure to enable a repository that contains the package. You don't need to enable more repositories, if you're using an RHEL 8.x HA-enabled image.
+1. **[A]** Install the SAP HANA resource agents on **all nodes**. Make sure to enable a repository that contains the package. You don't need to enable more repositories, if you're using an RHEL 8.x or higher HA-enabled image.
 
    ```bash
    # Enable repository that contains SAP HANA resource agents
    sudo subscription-manager repos --enable="rhel-sap-hana-for-rhel-7-server-rpms"
    
-   sudo yum install -y resource-agents-sap-hana
+   sudo dnf install -y resource-agents-sap-hana
    ```
 
    > [!NOTE]
    > For RHEL 8.x and RHEL 9.x, verify that the installed resource-agents-sap-hana package is version 0.162.3-5 or later.
 
-1. **[A]** Install the HANA `system replication hook`. The hook needs to be installed on both HANA DB nodes.
-
-   > [!TIP]
-   > The Python hook can only be implemented for HANA 2.0.
-
-   1. Prepare the hook as `root`.
-
-       ```bash
-        mkdir -p /hana/shared/myHooks
-        cp /usr/share/SAPHanaSR/srHook/SAPHanaSR.py /hana/shared/myHooks
-        chown -R hn1adm:sapsys /hana/shared/myHooks
-       ```
+1. **[A]** Install the HANA `system replication hooks`. The configuration for the replication hooks needs to be installed on both HANA DB nodes.
 
    1. Stop HANA on both nodes. Run as <sid\>adm.
 
@@ -470,13 +349,24 @@ This important step optimizes the integration with the cluster and improves the
        ```output
        [ha_dr_provider_SAPHanaSR]
        provider = SAPHanaSR
-       path = /hana/shared/myHooks
+       path = /usr/share/SAPHanaSR/srHook
        execution_order = 1
-        
+
+       [ha_dr_provider_chksrv]
+       provider = ChkSrv
+       path = /usr/share/SAPHanaSR/srHook
+       execution_order = 2
+       action_on_lost = kill
+    
        [trace]
        ha_dr_saphanasr = info
+       ha_dr_chksrv = info
        ```
 
+   If you point parameter `path` to the default `/usr/share/SAPHanaSR/srHook` location, the Python hook code updates automatically through OS updates or package updates. HANA uses the hook code updates when it next restarts. With an optional own path like `/hana/shared/myHooks`, you can decouple OS updates from the hook version that HANA will use.
+
+   You can adjust the behavior of `ChkSrv` hook by using the `action_on_lost` parameter. Valid values are [ `ignore` | `stop` | `kill` ].
+
 1. **[A]** The cluster requires `sudoers` configuration on each cluster node for <sid\>adm. In this example, that's achieved by creating a new file. Use the `visudo` command to edit the `20-saphana` drop-in file as `root`.
 
     ```bash
@@ -500,7 +390,7 @@ This important step optimizes the integration with the cluster and improves the
     sapcontrol -nr 03 -function StartSystem 
     ```
 
-1. **[1]** Verify the hook installation. Run as <sid\>adm on the active HANA system replication site.
+1. **[1]** Verify the SRHanaSR hook installation. Run as <sid\>adm on the active HANA system replication site.
 
     ```bash
      cdtrace
@@ -514,7 +404,14 @@ This important step optimizes the integration with the cluster and improves the
      # 2021-04-12 21:37:04.898680 ha_dr_SAPHanaSR SOK
     ```
 
-For more information on the implementation of the SAP HANA System Replication hook, see [Enable the SAP HA/DR provider hook](https://access.redhat.com/articles/3004101#enable-srhook).
+1. **[1]** Verify the ChkSrv hook installation. Run as <sid\>adm on the active HANA system replication site.
+
+    ```bash
+     cdtrace
+     tail -20 nameserver_chksrv.trc
+    ```
+
+For more information on the implementation of the SAP HANA hooks, see [Enabling the SAP HANA srConnectionChanged() hook](https://docs.redhat.com/en/documentation/red_hat_enterprise_linux_for_sap_solutions/8/html-single/automating_sap_hana_scale-up_system_replication_using_the_rhel_ha_add-on/index#con_enable_hook_automating-sap-hana-scale-up-system-replication) and [Enabling the SAP HANA srServiceStateChanged() hook for hdbindexserver process failure action (optional)](https://docs.redhat.com/en/documentation/red_hat_enterprise_linux_for_sap_solutions/8/html-single/automating_sap_hana_scale-up_system_replication_using_the_rhel_ha_add-on/index#con_enable_hdbindexserver_automating-sap-hana-scale-up-system-replication).
 
 ## Create SAP HANA cluster resources
 
