VEOS Administrator Guide

VEOS is a multi-user Linux-based operating system for managing telecom services.
This guide contains basic operating principles, administration commands, and configuration examples.

Key VEOS features:

• Compatibility with standard Linux commands and utilities
• Management through the bash command shell (default)
• File system compliant with the FHS standard
• Initialization through systemd
• Access control based on users and groups

A process is a program loaded into the server memory and currently being executed. Processes are divided into two types:

Commands for process management:

A process can run without user interaction (in the background). Use & to move it to the background. If the process requires input, it will be stopped by the kernel until returned to normal mode.

# Run a script in the background
./backup.sh &
 
# View background jobs in the current session
jobs

VEOS uses a hierarchical Linux file system — a single tree starting from the root /. Different partitions and devices are mounted into directories (mount points).

Most important directories:

Devices are displayed in /dev/:

Minimum partitions required for VEOS installation:

• Root partition /
• swap partition (recommended size — from one to two times the amount of RAM)
• Optional: separate partitions for /home, /var, /usr

Bash (Bourne Again Shell) is the primary shell in VEOS.

Example of a pipe with sorting:

# Sort the list of files in /etc in reverse order
ls -la /etc | sort -r

Users are identified by UID (numeric identifier), groups by GID.

Each user belongs to at least one group (with the same name).
Additional groups are assigned using usermod -G.

Example of adding a user to the wheel group (for sudo access):

usermod -G wheel test

View user groups:

id test

The superuser (root) has unrestricted access to all files and processes.

Why su - is important:
Without the hyphen, the $PATH and $HOME variables remain from the regular user, and commands from /sbin and /usr/sbin may be unavailable.

Allows executing individual commands as root without fully switching users.
To use sudo, the user must belong to the wheel group.

systemd is the primary initialization system in VEOS. It starts services in parallel and tracks dependencies.

Example for the fastdpi service:

systemctl start fastdpi.service
systemctl status fastdpi.service
systemctl enable fastdpi.service

Example:

journalctl -u fastdpi.service -b

Question: Which command shell is used in VEOS by default?
Answer: bash. You can check it using echo $SHELL.

Question: How do I obtain root privileges with the full environment?
Answer: Run su -. Make sure to include the hyphen.

Question: What is systemd and how is it better than sysvinit?
Answer: systemd starts services in parallel, which speeds up boot time, and it does not stop the entire process if one service hangs.

Question: Which two hard disk partitions are required for VEOS?
Answer: The root partition / and the swap partition.

Question: How do I view logs for a specific service?
Answer: Use journalctl -u service_name.service.

Question: Can sudo be used in VEOS?
Answer: Yes, if the user is added to the wheel group. Example: sudo systemctl restart fastdpi.