Configuring User Permissions

If the Hadoop installation user is a common user, the HAF and OmniData installation user must be the same as the Hadoop installation user, and HAF and OmniOffload must be installed in the common user directory.

All commands in this section are for reference in the following scenarios. Change the values based on your requirements.

The installation user is omm.
The software package is stored in /home/omm/omnidata-software.
If the installation directory is /home/omm/omnidata-install, OmniData is installed in /home/omm/omnidata-install/omnidata. On compute nodes, HAF is installed in /home/omm/omnidata-install/haf-host; on offload nodes, HAF is installed in /home/omm/omnidata-install/haf-offload.
The cgroup subdirectory is omm. For details, see Prerequisites for Installing OmniData.

Prerequisites for Installing OmniData

Before installing OmniData on the offload node as a common user, perform the following operations as the root user first:

Grant the permission for creating scheduled tasks to the current user. If the current user is omm. Run the following command:
```
echo "omm"  >> /etc/cron.allow
```

To control the CPU used by applications running in OmniData, create a cgroup subdirectory for the current user. Assume that the current user is omm and the subdirectory is omm. Run the following commands:
```
cd /sys/fs/cgroup/cpu
mkdir omm
chown -R omm:omm omm
```

To ensure system security, disable remote login for user omm who installs and runs OmniData. That is, set the permission of user omm to nologin.
You do not need to perform the preceding operations when installing OmniOffload on compute nodes.
When using the root user for installation, you do not need to configure a scheduled task, but you need to create a subdirectory in /sys/fs/cgroup/cpu.
The cgroup subdirectory name must be the same as the current user name.

Parent topic: Preparations