Your Host Dada Unmanaged VPS is a Linux server that you control as root. This guide covers the essential first steps: logging in over SSH, checking your VPS's RAM, disk, CPU and IP address, installing updates, creating a sudo user, switching to SSH keys, turning on a firewall and rebooting safely.
Before you start
- Find your VPS's IP address and root password. These are in your VPS welcome email and on the VPS's page under Services in the Client Area.
- You'll need an SSH program. Windows 10 and 11, macOS and Linux all include the
sshcommand: open Terminal (Mac and Linux) or Windows Terminal / PowerShell (Windows). - Commands below are shown for both families. AlmaLinux uses
dnf; Ubuntu and Debian useapt. Replace203.0.113.10with your VPS's IP address andalexwith the username you want.
1. Log in as root
ssh root@203.0.113.10The first time, you'll be asked to confirm the server's fingerprint. Type yes, then enter the root password (nothing appears as you type, which is normal). If you've just received the VPS, change the root password straight away with passwd.
2. Check your VPS's RAM, disk, CPU and IP address
| To check | Command | What to look at |
|---|---|---|
| Memory (RAM) and swap | free -h | The total and available columns |
| Disk space | df -h | The line mounted on /: size, used and available |
| CPU cores | nproc or lscpu | Number of cores and CPU model |
| IP addresses | ip a or hostname -I | The inet address on your main network interface (for example eth0 or ens3) |
| Operating system | cat /etc/os-release | The PRETTY_NAME line |
| Virtualisation type | systemd-detect-virt | For example kvm |
| Uptime and load | uptime | How long since the last reboot and the load averages |
3. Install updates
AlmaLinux 9:
dnf -y updateUbuntu 22.04 and Debian 12:
apt update && apt -y upgradeIf the kernel was updated, reboot afterwards (see step 7).
4. Create a user with sudo rights
Working as root all the time is risky. Create your own user and give it administrator (sudo) rights.
AlmaLinux 9:
adduser alex
passwd alex
usermod -aG wheel alexUbuntu 22.04 and Debian 12:
adduser alex
usermod -aG sudo alexOn a minimal Debian install, sudo may not be installed yet. Add it with apt install sudo. Open a second terminal and check you can log in as the new user and run sudo whoami (it should print root) before carrying on.
5. Switch to SSH keys
SSH keys are far harder to break than passwords. On your own computer (not the VPS), create a key pair if you don't already have one:
ssh-keygen -t ed25519Copy the public key to the VPS. On Mac and Linux:
ssh-copy-id alex@203.0.113.10On Windows, ssh-copy-id isn't available, so run this in PowerShell instead:
type $env:USERPROFILE\.ssh\id_ed25519.pub | ssh alex@203.0.113.10 "mkdir -p ~/.ssh && chmod 700 ~/.ssh && cat >> ~/.ssh/authorized_keys && chmod 600 ~/.ssh/authorized_keys"Check that ssh alex@203.0.113.10 now logs you in without asking for the account password. Then, on the VPS, turn off password logins and direct root logins by creating a settings file:
sudo nano /etc/ssh/sshd_config.d/01-hardening.confAdd these two lines and save:
PasswordAuthentication no
PermitRootLogin noApply the change. On AlmaLinux: sudo systemctl restart sshd. On Ubuntu and Debian: sudo systemctl restart ssh.
6. Turn on a firewall
Allow SSH first, then any services you run, such as a website on ports 80 and 443.
AlmaLinux 9 (firewalld):
sudo dnf -y install firewalld
sudo systemctl enable --now firewalld
sudo firewall-cmd --permanent --add-service=ssh
sudo firewall-cmd --permanent --add-service=http --add-service=https
sudo firewall-cmd --reload
sudo firewall-cmd --list-allUbuntu 22.04 and Debian 12 (ufw):
sudo apt -y install ufw
sudo ufw allow 22/tcp
sudo ufw allow 80,443/tcp
sudo ufw enable
sudo ufw status7. Reboot safely
Reboot after kernel updates, and whenever the server tells you a restart is needed:
- Ubuntu and Debian: if the file
/var/run/reboot-requiredexists, a reboot is needed. - AlmaLinux:
sudo dnf needs-restarting -rtells you whether a reboot is needed.
sudo rebootYour SSH session will disconnect. Wait a minute or two, then log back in. Check that your services started again with systemctl --failed (it should list nothing).
Reboot, reinstall or reset the root password from outside the server
If you can't log in over SSH, for example after a firewall mistake or a lost password, open your VPS under Services in the Client Area. Where the page offers power, reinstall or password options, you can use them there. Otherwise open a ticket and we'll reboot the VPS, reset the root password or reinstall the operating system for you.
Next steps
- Automatic security updates: on Ubuntu and Debian, install
unattended-upgrades. On AlmaLinux, installdnf-automaticand enable its timer. - Backups: an unmanaged VPS isn't backed up by us. Copy important data off the server regularly.
- Brute-force protection: consider a tool such as Fail2ban to block repeated failed logins.
Troubleshooting
"Connection refused" or "Connection timed out"
Check you're using the right IP address. If it worked before, a firewall rule may be blocking SSH, or the VPS may be off. Ask us to reboot it or check it from outside.
"Permission denied (publickey)"
Password logins are switched off and your key isn't being offered. Make sure you're logging in as the user whose ~/.ssh/authorized_keys holds your key, from the computer that has the matching private key.
"WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED"
This is expected after a reinstall, because the server has new keys. Remove the old entry on your computer with ssh-keygen -R 203.0.113.10 and connect again. If you haven't reinstalled, contact us before continuing.
Last reviewed: October 2026
