Daily Uses Linux Command Related to Hana

Daily Uses Linux Command Related to Hana

🖥️ Focus: OS-Level Preparation, Commands, Configuration, Troubleshooting

📦 Platforms: SUSE Linux Enterprise Server (SLES), Red Hat Enterprise Linux (RHEL)

Section 1: Linux Basics for HANA (Q1–Q15)

Which Linux distributions are supported for HANA?
SUSE Linux Enterprise Server (SLES) and Red Hat Enterprise Linux (RHEL)
How to check the OS version?
cat /etc/os-release
Which command shows the kernel version?
uname -r
Which user is used for SAP HANA installation?
root
What command shows CPU info?
lscpu
How to check RAM in Linux?
free -g or cat /proc/meminfo
Which command lists running processes?
top or htop
How to check disk space usage?
df -h
How to check free inodes?
df -i
How to check mounted filesystems?
mount or cat /etc/fstab
How to check current hostname?
hostname or hostnamectl
How to set hostname permanently?
hostnamectl set-hostname <newname>
Which command shows all network interfaces?
ip addr or ifconfig
How to check system uptime?
uptime
How to check OS architecture (32/64-bit)?
uname -m

Section 2: File System & Storage (Q16–Q30)

What file system is recommended for /hana?
XFS
How to create a new XFS filesystem?
mkfs.xfs /dev/sdX
How to mount a file system?
mount /dev/sdX /mnt/hana
How to make a mount persistent?
Add entry in /etc/fstab
Which command checks filesystem usage?
df -Th
How to list block devices?
lsblk
What is LVM?
Logical Volume Manager – manages disk volumes.
How to extend a logical volume?
lvextend -L +10G /dev/mapper/vg-lv → xfs_growfs /mountpoint
Which command creates partitions?
fdisk or parted
How to check filesystem errors?
fsck
How to mount NFS share?
mount -t nfs <server>:/share /mnt
What is the purpose of /hana/data?
Stores HANA main data files.
Purpose of /hana/log?
Stores redo logs for HANA transactions.
Purpose of /hana/shared?
Stores binaries, configuration, and shared files.
How to create directories with specific permissions?
mkdir -p /path && chmod 755 /path

Section 3: Package Management (Q31–Q45)

What is the package manager in SLES?
zypper
How to install a package using zypper?
zypper install <package>
How to list installed packages?
zypper se --installed-only
How to update system packages?
zypper update
How to check repository status?
zypper lr
How to refresh repository metadata?
zypper refresh
What is the package manager in RHEL?
yum or dnf
How to install software in RHEL?
yum install <package> or dnf install
How to remove a package?
zypper rm <package>
How to install a local RPM file?
rpm -ivh <file>.rpm
How to list kernel packages?
rpm -qa | grep kernel
Which libraries are mandatory for HANA?
glibc, libaio1, libstdc++, numactl, uuidd
How to check if libaio is installed?
rpm -qa | grep libaio
How to install saptune?
zypper install saptune
Which SAP Note lists required packages for HANA?
Check SAP Note 2772999 or equivalent for your OS.

Section 4: System Tuning & Optimization (Q46–Q65)

What is saptune used for?
Applies SAP-recommended OS tuning.
How to apply HANA tuning profile?
saptune solution apply HANA
How to start saptune service?
systemctl start saptune
How to enable saptune on boot?
systemctl enable saptune
How to verify if tuning applied?
saptune note verify
Which file contains kernel parameters?
/etc/sysctl.conf
How to apply sysctl changes immediately?
sysctl -p
What is the vm.nr_hugepages parameter?
Defines hugepages for memory performance.
How to check hugepages allocation?
cat /proc/meminfo | grep Huge
How to calculate required hugepages?
Based on RAM size and page size (usually 2MB)
What is the use of numactl?
NUMA support for memory allocation optimization.
How to install numactl?
zypper install numactl
How to check NUMA node memory?
numactl --hardware
How to check CPU affinity for a process?
taskset -c -p <PID>
Why is swap needed in HANA?
As a safety buffer; recommended: 1x RAM.
How to check swap usage?
swapon -s and free -m
How to increase swap space?
Create a swap file → mkswap → swapon
What’s the purpose of limits.conf?
To control user resource limits (e.g., file descriptors)
Where is limits.conf located?
/etc/security/limits.conf
How to apply user limits for SAP?
Add entries for sidadm and sapadm in limits.conf

Section 5: Networking, Services, & Logs (Q66–Q80)

How to view open ports?
netstat -tulnp or ss -tuln
How to check DNS resolution?
nslookup <hostname>
How to restart network service?
systemctl restart network (SLES/RHEL 7+)
Which file configures hostname resolution?
/etc/hosts
How to disable firewall temporarily?
systemctl stop firewalld
How to check listening ports in HANA?
netstat -anp | grep hdb
How to configure static IP?
Edit files in /etc/sysconfig/network/ or use nmtui
Which service manages startup scripts?
systemd
How to enable service at boot?
systemctl enable <service>
How to disable a service?
systemctl disable <service>
Where are system logs stored?
/var/log/
What is the main system log file?
/var/log/messages
How to read journal logs?
journalctl
How to read SAP logs?
/usr/sap/<SID>/HDB<instance>/trace
How to check service status?
systemctl status <service>

Section 6: User Management & Permissions (Q81–Q95)

How to create a new user?
useradd <username>
How to set a user password?
passwd <username>
How to switch users?
su - <username>
Which users are created during HANA install?
sidadm and sapadm
What is the purpose of sapadm?
Admin user for SAP Host Agent.
How to list groups of a user?
groups <username>
Where are user accounts stored?
/etc/passwd
How to give sudo privileges to a user?
Add to /etc/sudoers
How to view currently logged-in users?
who or w
How to check user history?
cat ~/.bash_history
What is chown used for?
Change ownership of files.
How to set file permissions?
chmod 755 <file>
What is umask?
Default file permission setting for new files.
How to change user shell?
chsh -s /bin/bash <username>
How to check user’s environment variables?
env

Section 7: Troubleshooting HANA on Linux (Q96–Q100)

What causes HANA install failure on Linux?
Missing dependencies, wrong OS version, disk issues.
Where to find hdblcm logs?
/var/tmp/ and logs/ under install dir.
Which file controls memory limits?
/etc/security/limits.conf
How to troubleshoot failed systemd service?
systemctl status <service> and journalctl -xe
What to check if HANA doesn’t start?
Check logs in /usr/sap/<SID>/HDB<instance>/trace, permissions, disk space, and services.