Configure SLES 12/15 for SAP

To configure SLES 12/15 for SAP

1. After your instance is up and running, connect to the instance by using Secure Shell (SSH) and the key pair that you used to launch the instance.

   Note

   Depending on your network and security settings, you might have to first connect by using SSH to a bastion host before accessing your SAP HANA instance, or you might have to add IP addresses or ports to the security group to allow SSH access.

2. Switch to root user.

   Alternatively, you can use sudo to execute the following commands as ec2-user.

3. Set a hostname and fully qualified domain name (FQDN) for your instance by executing the hostnamectl command and updating the /etc/hostname file.

     # hostnamectl set-hostname --static your_hostname
     # echo your_hostname.example.com > /etc/hostname

   Open a new session to verify the hostname change.

4. Ensure that the DHCLIENT_SET_HOSTNAME parameter is set to no to prevent DHCP from changing the hostname during restart.

     # grep DHCLIENT_SET_HOSTNAME /etc/sysconfig/network/dhcp

5. Set the preserve_hostname parameter to true to ensure your hostname is preserved during restart.

     # sed -i '/preserve_hostname/ c\preserve_hostname: true' /etc/cloud/cloud.cfg

6. Add an entry to the /etc/hosts file with the new hostname and IP address.

     ip_address hostname.example.com hostname

7. If you are using a BYOS SLES for SAP image, register your instance with SUSE. Ensure that your subscription is for SLES for SAP.

     # SUSEConnect -r Your_Registration_Code
     # SUSEConnect -s

8. Ensure that the following packages are installed:

   systemd, tuned, saptune, libgcc_s1, libstdc++6, cpupower, autofs, nvme-cli, libssh2-1, libopenssl1_0_0

   You can use the rpm command to check whether a package is installed.

     # rpm -qi package_name

   You can then use the zypper install command to install the missing packages.

     # zypper install package_name

   Note

   If you are importing your own SLES image, additional packages might be required to ensure that your instance is optimally setup. For the latest information, refer to the Package List section in the SLES for SAP Application Configuration Guide for SAP HANA, which is attached to SAP OSS Note 1944799

9. Ensure that your instance is running on a kernel version that is recommended in SAP OSS Note 2205917 or 2684254 depending on your version. If needed, update your system to meet the minimum kernel version. You can check the version of the kernel and other packages by using the following command:

     # rpm -qi kernel*

10. Start saptune daemon and use the following command to set it to automatically start when the system reboots.

      # saptune daemon start

11. Check whether the force_latency parameter is set in the saptune configuration file.

      # grep force_latency /usr/lib/tuned/saptune/tuned.conf

    If the parameter is set, skip the next step and proceed with activating the HANA profile with saptune.

12. Update the saptune HANA profile according to SAP OSS Note 2205917, and then run the following commands to create a custom profile for SAP HANA. This step is not required if the force_latency parameter is already set.

      # mkdir /etc/tuned/saptune
      # cp /usr/lib/tuned/saptune/tuned.conf /etc/tuned/saptune/tuned.conf
      # sed -i "/\[cpu\]/ a force_latency=70" /etc/tuned/saptune/tuned.conf
      # sed -i "s/script.sh/\/usr\/lib\/tuned\/saptune\/script.sh/"

13. Switch the tuned profile to HANA and verify that all settings are configured appropriately.

      # saptune solution apply HANA
      # saptune solution verify HANA

14. Configure and start the Network Time Protocol (NTP) service. You can adjust the NTP server pool based on your requirements; for example:

    Note

    Remove any existing invalid NTP server pools from /etc/ntp.conf before adding the following.

      # echo "server 0.pool.ntp.org" >> /etc/ntp.conf
      # echo "server 1.pool.ntp.org" >> /etc/ntp.conf
      # echo "server 2.pool.ntp.org" >> /etc/ntp.conf
      # echo "server 3.pool.ntp.org" >> /etc/ntp.conf
      # systemctl enable ntpd.service
      # systemctl start ntpd.service
          

    Tip

    Instead of connecting to the global NTP server pool, you can connect to your internal NTP server if needed. Or you can use Amazon Time Sync Service to keep your system time in sync.

15. Set the clocksource to tsc by updating the current_clocksource file and the GRUB2 boot loader.

      # echo "tsc" > /sys/devices/system/clocksource/*/current_clocksource
      # cp /etc/default/grub /etc/default/grub.backup
      # sed -i '/GRUB_CMDLINE_LINUX/ s|"| clocksource=tsc"|2' /etc/default/grub
      # grub2-mkconfig -o /boot/grub2/grub.cfg

16. Reboot your system for the changes to take effect.

17. Continue with storage configuration for SAP HANA.