Requirements

Server

Network size	CPU	RAM	Disk	Database
Up to 300 devices	2 vCPU	4 GB	40 GB	SQLite (default)
300 – 2,000 devices	4 vCPU	8 GB	100 GB	SQLite or PostgreSQL
More than 2,000 devices	8 vCPU	16 GB	200 GB+	PostgreSQL (see PostgreSQL)

Approximate values. Disk usage grows with the number of saved versions and firmware images; you can limit the versions kept per device in Administration → Settings → Change workflow.

• Ubuntu Server 22.04 LTS or 24.04 LTS, 64-bit, freshly installed (physical or virtual machine).
• A user account with sudo.
• Internet access during installation (Ubuntu and Python packages are downloaded).
• A fixed IP and a DNS name are recommended.

Network

From	To	Port	Purpose
Administrators’ browsers	Server	TCP 443 (and 80)	Web interface
Server	Network devices	TCP 22 (SSH) or 23 (Telnet)	Backups, changes, firmware (SCP over SSH)
Network devices	Server	UDP 514	Syslog: real-time change detection
Server	Internet	TCP 443	Optional: NVD (CVE), Cisco EoX API, Telegram, webhooks
Server	Mail server	TCP 587 / 465 / 25	Optional: alerts and reports by email

On the network devices

• SSH enabled and a user for OpenNCCM (ideally a dedicated one, with privileges to view and change the configuration).
• For firmware upgrades on Cisco: ip scp server enable.

Prepare the server

Connect to the server over SSH (from Windows you can use PowerShell, PuTTY or Windows Terminal):

ssh USER@SERVER_IP

There is nothing else to prepare: the installer updates Ubuntu, installs the dependencies and asks for the time zone. The time zone and clock can also be changed later in System → Date and time. Just check that the server clock is synchronized (timedatectl should show “NTP service: active”) and, if you like, change the host name:

timedatectl
sudo hostnamectl set-hostname opennccm     # optional

Recommendation

If the server is a virtual machine, take a snapshot now. It lets you return to this point if something goes wrong during the installation.