How to Install ISPConfig 3 on Ubuntu 24.04 VPS: Multi-Server Hosting Control Panel

ISPConfig 3 is the only free, open-source hosting control panel that natively supports splitting web, mail, DNS, and database roles across dedicated servers from a single web UI. That makes it the panel of choice for independent hosting providers, agencies running dozens of customer sites, and internal platform teams who want the capabilities of cPanel or Plesk without the per-server license fees. This guide walks you through a production-ready install of ISPConfig 3.2 on Ubuntu 24.04 LTS, covering the auto-installer, manual Perfect Server path, mail stack with Postfix and Dovecot, DNS with BIND9, Let's Encrypt, backups, and the jump to full multi-server mode.

Prefer a pre-built panel? Deploy the CloudCore Professional VPS and follow this guide end-to-end on hardware sized for ISPConfig's full mail-filtering stack.

Table of Contents

What is ISPConfig 3?

ISPConfig is an open-source multi-server hosting control panel maintained by Projektfarm GmbH since 2005. Unlike panels that assume all services run on a single box, ISPConfig was built from day one around the idea of a central master node that orchestrates configuration across independent web, mail, DNS, database, and mirror servers. When you create a website in the UI, the master writes the vhost to the correct web node; when you add a mailbox, it pushes the user to the dedicated mail node; when you publish a DNS zone, it replicates to every DNS node in the cluster.

The panel supports Apache 2.4 and Nginx as web servers, PHP 7.4 through 8.3 via PHP-FPM with per-site version switching, MariaDB or MySQL as the database engine, Postfix with Dovecot for SMTP and IMAP, Amavis + SpamAssassin + ClamAV for mail filtering, BIND9 or PowerDNS as the DNS server, PureFTPd for FTP with per-site quotas, and Jailkit for chrooted SSH. Everything is stitched together by a config queue that each node polls every minute, so the system is resilient to temporary network partitions.

ISPConfig 3.2 brought native Let's Encrypt integration via acme.sh, rspamd as an alternative to Amavis, modern UI themes, a REST API for automation, and better support for containerised installs. The 3.3 line (currently in development) is focused on FastCGI improvements and richer quota reporting.

Why Self-Host a Control Panel?

Running your own panel on a VPS you control, rather than paying for managed hosting or a commercial panel license, unlocks a handful of concrete advantages.

• No per-server license fee. cPanel costs USD 17+ per month per server for a modest account tier and scales upward steeply. Plesk is in a similar range. ISPConfig is free for unlimited servers, domains, and mailboxes.
• Full root access. You own the kernel, the firewall, and the backup policy. There is no hosting provider sitting above your OS limiting what you can install or how you tune the mail stack.
• Predictable, flat-rate cost. A single VPS priced at EUR 19.99 per month hosts dozens of small sites. Shared hosting that bundles a panel often caps you at 10-20 sites and charges per mailbox.
• Multi-tenant by design. ISPConfig's client/reseller model is built for agencies and resellers. Each client gets their own login with resource limits you define, without you ever exposing root.
• Native multi-server scaling. When your single box gets full, you add a second node, assign it the mail role, and move customers across with a few clicks. No panel rebuild, no data export.
• Privacy and GDPR. Your customer data, mailboxes, and DNS zones live on hardware you choose, in a region you choose, under a log retention policy you set.
• Automation-friendly. Every feature in the UI is backed by a JSON-RPC and REST API, so you can plug ISPConfig into provisioning systems, billing software, or CI pipelines.

Cost Comparison: ISPConfig vs Managed Panels

ISPConfig vs cPanel, Plesk, HestiaCP, CyberPanel

Each panel has a niche. ISPConfig wins on cost, multi-server, and openness. The others have their strengths too:

• HestiaCP - modern fork of VestaCP, excellent single-server experience, simpler UI, no multi-server mode.
• CyberPanel - built on OpenLiteSpeed, fastest WordPress performance out of the box, good for WP-heavy hosts.
• Plesk - polished UX, huge extension marketplace, commercial license, stronger Windows support.

Prerequisites

Before you begin, make sure you have:

• A VPS running Ubuntu 24.04 LTS (Noble Numbat) with root SSH access.
• At least 4 GB of RAM and 2 vCPU for a single-server install. 6 vCPU and 12 GB RAM is realistic for production with active mail filtering.
• At least 40 GB of disk space to hold the OS, the panel, customer sites, mailboxes, and ClamAV virus definitions (which alone occupy 3-4 GB in memory).
• A fully-qualified domain name you control, with DNS pointing an A record (and ideally a PTR record at your provider) to the server's public IP. Example: panel.example.com.
• Port 25 unblocked outbound. Many low-cost cloud providers block outbound SMTP by default. Confirm with support before installing.

Recommended Plan: CloudCore Professional

For a single-server ISPConfig install that hosts 15-30 active sites with mail filtering turned on, we recommend the CloudCore Professional plan:

- 6 vCPU cores

- 12 GB RAM

- 100 GB NVMe SSD

- Unmetered bandwidth

- EUR 19.99/month

The 12 GB of RAM matters because ClamAV loads its full signature database into memory on startup, and Amavis forks workers that each carry their own Perl interpreter. Underspec and your mail queue will stall under load.

Connect to your server via SSH to get started:

ssh root@your-server-ip

Step 1: Prepare the Server

ISPConfig is fussy about hostname and /etc/hosts entries because it uses the FQDN to identify nodes in the cluster. Get this right on day one.

Set the hostname to a fully-qualified subdomain:

sudo hostnamectl set-hostname panel.example.com

Edit /etc/hosts so the hostname resolves correctly locally:

sudo nano /etc/hosts

Ensure a line like the following exists, substituting your public IP and FQDN:

127.0.0.1       localhost
203.0.113.10    panel.example.com panel

Verify the FQDN resolves correctly:

hostname -f

Expected output:

panel.example.com

Update the package index and upgrade everything to current:

sudo apt update && sudo apt upgrade -y

Install the essentials the installer expects:

sudo apt install -y curl wget sudo gnupg2 lsb-release software-properties-common rsyslog ufw

Set the timezone (adjust to your region):

sudo timedatectl set-timezone UTC

Enable the firewall with the ports ISPConfig needs:

sudo ufw allow OpenSSH
sudo ufw allow 20,21,22,25,53,80,110,143,443,465,587,993,995,8080,8081,53/tcp
sudo ufw allow 53/udp
sudo ufw --force enable

Reboot to ensure the kernel and hostname are clean:

sudo reboot

Reconnect after a minute and confirm the hostname:

hostname -f

Step 2: Install with the Official Auto-Installer

The ISPConfig team maintains an official one-command installer that provisions the full stack on a clean Ubuntu 24.04 server. This is the recommended path unless you need specific customisation.

Run the auto-installer:

wget -O - https://get.ispconfig.org | sh -s -- --use-ftp-ports=40110-40210 --unattended-upgrades

The script will prompt for a handful of choices early on:

The installer takes 10-20 minutes depending on your bandwidth. Expected end-of-run output:

[INFO] ISPConfig installation complete.
[INFO] Panel URL: https://panel.example.com:8080
[INFO] Admin username: admin
[INFO] Admin password: <random 16-char string>
[INFO] MariaDB root password: <random 16-char string>
[INFO] Credentials also saved to /root/.ispconfig_install.log

Write the credentials down immediately. The log file is root-readable only.

What the Auto-Installer Does

Under the hood the installer performs these actions on your behalf:

Skip to Step 4 if the auto-installer completed successfully. The manual path below is only for users who need component-level control.

Step 3: Manual Install (Perfect Server Path)

If you prefer a hands-on install, the ISPConfig team maintains a detailed Perfect Server guide. The short form is reproduced below for reference. Skip this section if you ran the auto-installer.

3.1 Install MariaDB

sudo apt install -y mariadb-server mariadb-client
sudo mysql_secure_installation

Answer Y to all hardening prompts and set a strong root password.

3.2 Install Postfix and Dovecot

sudo apt install -y postfix postfix-mysql postfix-doc dovecot-core dovecot-imapd dovecot-pop3d dovecot-lmtpd dovecot-mysql dovecot-sieve dovecot-managesieved

When prompted for the Postfix configuration type, choose Internet Site and set the mail name to your FQDN (panel.example.com).

3.3 Install Amavis, SpamAssassin, and ClamAV

sudo apt install -y amavisd-new spamassassin clamav clamav-daemon opendkim opendkim-tools
sudo systemctl enable --now clamav-daemon clamav-freshclam amavis

3.4 Install Apache with PHP

sudo apt install -y apache2 apache2-doc apache2-utils libapache2-mod-fcgid php-common php-cli php-fpm php-mysql php-gd php-curl php-imagick php-intl php-mbstring php-xml php-zip php-bcmath php-imap
sudo a2enmod rewrite ssl actions suexec fcgid proxy_fcgi
sudo systemctl restart apache2

For Nginx instead, install nginx and php8.3-fpm and skip the Apache modules.

3.5 Install BIND9 or PowerDNS

For BIND9 (default choice):

sudo apt install -y bind9 bind9utils bind9-doc dnsutils haveged

For PowerDNS with a MySQL backend:

sudo apt install -y pdns-server pdns-backend-mysql

3.6 Install PureFTPd and Jailkit

sudo apt install -y pure-ftpd-common pure-ftpd-mysql quota quotatool
sudo apt install -y build-essential autoconf automake libtool flex bison debhelper binutils

Jailkit is not in the Ubuntu repositories, so build from source:

cd /tmp
wget https://olivier.sessink.nl/jailkit/jailkit-3.3.1.tar.gz
tar xvzf jailkit-3.3.1.tar.gz
cd jailkit-3.3.1
echo 5 > debian/compat
./debian/rules binary
cd ..
sudo dpkg -i jailkit_*.deb
rm -rf jailkit-3.3.1*

3.7 Install ISPConfig 3.2

cd /tmp
wget https://www.ispconfig.org/downloads/ISPConfig-3.2.12.tar.gz
tar xfz ISPConfig-3.2.12.tar.gz
cd ispconfig3_install/install/
sudo php -q install.php

Answer the prompts (language, country, MariaDB credentials, SSL for the panel), and the installer will wire everything together. Expect a 5-10 minute run.

Step 4: Choose Apache or Nginx

Both web servers are first-class citizens in ISPConfig. The choice matters for how you configure websites later.

Choose Apache when:

• You host mixed PHP apps that rely on .htaccess files (classic WordPress, Laravel, custom legacy stacks).
• You want per-site FastCGI sandboxing with mpm_itk or suEXEC.
• Your team is more familiar with Apache rewrite rules.

• You prioritise raw static-file throughput and concurrent connections.
• You are running mostly CMS apps with server-side routing you can express in Nginx location blocks.
• You plan to offload TLS termination to Nginx in front of an application backend.

Verify the web server is running:

sudo systemctl status apache2    # or nginx

Confirm PHP-FPM pools are live:

sudo systemctl status php8.3-fpm

Step 5: Verify the Mail Stack

Check each mail component:

sudo systemctl status postfix dovecot amavis clamav-daemon

All four should show active (running). Verify Postfix is listening on ports 25, 465, and 587:

sudo ss -tlnp | grep master

Expected output:

LISTEN 0  100  0.0.0.0:25   0.0.0.0:*  users:(("master",pid=1234,fd=13))
LISTEN 0  100  0.0.0.0:465  0.0.0.0:*  users:(("master",pid=1234,fd=64))
LISTEN 0  100  0.0.0.0:587  0.0.0.0:*  users:(("master",pid=1234,fd=69))

Verify Dovecot is listening on 143, 993, 110, and 995:

sudo ss -tlnp | grep dovecot

Check the SpamAssassin and ClamAV handoff by sending a test message after you create your first mailbox in Step 9.

Step 6: Configure DNS (BIND9 or PowerDNS)

ISPConfig manages DNS zones through the Sites module and pushes them to BIND9 or PowerDNS on the selected DNS nodes.

For BIND9, confirm the daemon is running and listening on port 53:

sudo systemctl status bind9
sudo ss -tulnp | grep ':53'

Set up a forwarder or root hints as required. The default Ubuntu BIND9 ships with root hints baked in, which is fine.

If you plan to use this server as an authoritative DNS server for customer domains, you also need:

For PowerDNS, verify the MySQL backend is populated:

sudo mysql -e "USE powerdns; SHOW TABLES;"

You should see domains, records, supermasters, and other PowerDNS-specific tables.

Step 7: PureFTPd and Jailkit SSH

FTP via PureFTPd and chrooted SSH via Jailkit are both installed by the auto-installer.

Verify PureFTPd:

sudo systemctl status pure-ftpd-mysql

Verify Jailkit is available:

which jk_init jk_chrootsh

Expected output:

/usr/sbin/jk_init
/usr/sbin/jk_chrootsh

When you create a shell user in ISPConfig later, the panel copies the necessary binaries into the chroot using jk_init. You do not need to configure anything manually.

Step 8: First Admin Login

Open the panel in your browser:

https://panel.example.com:8080

You may see a self-signed certificate warning if Let's Encrypt did not complete during install. Accept the warning temporarily; we will fix it in Step 10.

Log in with:

• Username: admin
• Password: the random password printed at the end of the installer (check /root/.ispconfig_install.log if you missed it).

Change the Admin Password

Immediately navigate to Tools -> User Settings -> Password and Language. Enter a strong password and save. ISPConfig logs password changes in the admin audit log.

Tour the Main Modules

The top navigation exposes the core modules:

• Dashboard - server stats, disk quotas, mail queue status.
• Client - add customers, set limits, manage reseller hierarchy.
• Sites - websites, FTP users, shell users, databases, subdomains.
• Email - domains, mailboxes, forwards, filters, whitelists, blacklists.
• DNS - zones, records, templates.
• System - server config, CLI, firewall, cron, remote users for API.
• Monitor - logs, server health, mail queue, RAID status.
• Help - support request form that emails the master admin.

Step 9: Create a Client, Site, Mailbox, and DNS Zone

Walk through the full customer creation flow once to confirm every module works end to end.

9.1 Create a Client

Go to Client -> Add new client. Fill in:

• Company name and contact name.
• Username (this becomes the panel login for the customer).
• A secure password.
• Limits: number of websites, mailboxes, FTP users, databases, DNS zones, disk quota, traffic quota.

9.2 Create a Website

Go to Sites -> Website -> Add new website:

• Server: the current host (or a specific web node in multi-server mode).
• IPv4 address: * to listen on all IPs.
• Domain: customer-domain.com.
• Client: select the client you just created.
• Document root is generated automatically as /var/www/customer-domain.com/web.
• PHP: select PHP-FPM and the version (7.4 through 8.3).
• Check Auto-subdomain: www so www.customer-domain.com also works.

9.3 Create a Mail Domain and Mailbox

Go to Email -> Domain -> Add new Domain:

• Server: the current host (or a dedicated mail node).
• Client: the client account.
• Domain: customer-domain.com.
• Check Active.

• Email: [email protected].
• Password: strong random string.
• Quota: 1024 MB (adjust per customer plan).
• Spam filter: Normal (uses SpamAssassin scoring).

9.4 Create a DNS Zone

Go to DNS -> Add DNS Zone with Wizard:

• Select the template Default (creates SOA, NS, and MX records automatically).
• Domain: customer-domain.com.
• IP: the server's public IP.
• NS1 and NS2: your nameserver FQDNs.
• Client: the client account.

dig @127.0.0.1 customer-domain.com NS +short

Expected output:

ns1.example.com.
ns2.example.com.

9.5 Test Mail End-to-End

From any external mail account send a test to [email protected]. Then log into the Roundcube webmail (installed by the auto-installer) at:

https://panel.example.com:8081

Log in as [email protected]. The test message should be in the inbox within a minute. Check that SpamAssassin has added X-Spam-* headers.

Step 10: Enable Let's Encrypt SSL

ISPConfig uses acme.sh as its ACME client. To issue a certificate for a site:

Within 60-120 seconds acme.sh issues the certificate, installs it into the vhost, and reloads the web server. Verify with:

curl -I https://customer-domain.com

You should see HTTP/2 200 and a valid certificate chain.

For the panel itself, edit /usr/local/ispconfig/interface/ssl/ after pointing the FQDN correctly and run:

sudo /usr/local/ispconfig/server/scripts/letsencrypt.sh

Then restart the panel:

sudo systemctl restart apache2    # or nginx

Certificates renew automatically via the system cron; no further action is needed.

Step 11: Configure Automated Backups

ISPConfig has a built-in backup module that snapshots websites and databases on a configurable rotation.

Go to System -> Server Config -> select your server -> Web tab:

• Backup directory: /var/backup.
• Backup mode: zip.
• Retention: 7 daily, 4 weekly, 6 monthly.

• Tick Backup interval: daily.
• Set copies to keep: 7.

sudo tee /etc/cron.daily/offsite-backup > /dev/null <<'EOF'
#!/bin/bash
rclone sync /var/backup b2:mycompany-ispconfig-backups \
  --log-file /var/log/offsite-backup.log
EOF
sudo chmod +x /etc/cron.daily/offsite-backup

Pair this with rclone or restic for deduplicated encrypted offsite copies.

Step 12: Scale to Multi-Server Mode

The killer feature of ISPConfig is true multi-server orchestration. Here is how to split mail, web, and database onto dedicated nodes.

12.1 Provision Additional VPS Instances

Spin up three additional Ubuntu 24.04 servers on CloudCore Professional plans. Set their FQDNs:

• web1.example.com
• mail1.example.com
• db1.example.com

12.2 Install ISPConfig in Slave Mode

On each slave, run the auto-installer with the slave flag:

wget -O - https://get.ispconfig.org | sh -s -- --no-mail --no-dns --use-ftp-ports=40110-40210

Adjust --no-mail, --no-dns, --no-mailman to disable the services you do not want on that slave. For example, the database node should skip web, mail, and DNS entirely.

12.3 Grant MySQL Access from Slaves to Master

On the master, create a remote MySQL user for each slave:

sudo mysql -e "CREATE USER 'ispcsrv2'@'web1.example.com' IDENTIFIED BY 'strongpassword';"
sudo mysql -e "GRANT SELECT ON dbispconfig.* TO 'ispcsrv2'@'web1.example.com';"
sudo mysql -e "FLUSH PRIVILEGES;"

Open MySQL port 3306 on the master firewall only to the slave IPs:

sudo ufw allow from 203.0.113.20 to any port 3306

12.4 Join the Slave to the Master

On the slave, edit /usr/local/ispconfig/server/lib/config.inc.php:

$conf['db_host']     = 'master.example.com';
$conf['db_user']     = 'ispcsrv2';
$conf['db_password'] = 'strongpassword';
$conf['db_database'] = 'dbispconfig';

Restart the ISPConfig server agent:

sudo systemctl restart ispconfig_server

Within two minutes the slave shows up in System -> Server services on the master. Tick the roles you want it to serve (Web, Mail, DNS, DB, FTP), save, and assign new customer resources to it.

12.5 Mirror and Failover

For HA, assign a mirror server to each primary role. The master replicates config to both, and you can switch clients between primary and mirror with a single dropdown change. Full HA requires shared storage or rsync of document roots; the panel manages the config layer, not the data layer.

Hardening Checklist

Production panels should go through this hardening checklist on day one.

• SSH: disable root password login, enforce key-based auth, change the default port away from 22.
• Fail2ban: confirm the ispconfig jail is enabled and banning brute-force attempts on port 8080.
• UFW: review allowed ports and trim anything you do not use.
• Amavis: enable DKIM signing for every mail domain.
• SPF, DKIM, DMARC: publish DNS records for every mail domain. ISPConfig generates the DKIM selector and records automatically.
• rspamd: consider swapping Amavis for rspamd for a 3-5x performance boost.
• Panel access: bind port 8080 to a VPN or whitelist office IPs via UFW.
• System updates: unattended-upgrades is on by default via the auto-installer; confirm with sudo systemctl status unattended-upgrades.
• Monitoring: deploy Uptime Kuma externally to watch port 8080, port 25, and port 443.
• Backup verification: restore a test site from backup monthly to confirm the pipeline works.

Troubleshooting

Useful Log Locations

• Panel: /var/log/ispconfig/ (cron.log, auth.log, httpd_error.log).
• Apache: /var/log/apache2/.
• Nginx: /var/log/nginx/.
• Postfix / Dovecot: /var/log/mail.log and /var/log/mail.err.
• BIND9: /var/log/syslog filtered by named.
• MariaDB: /var/log/mysql/error.log.

sudo multitail /var/log/ispconfig/cron.log /var/log/mail.log /var/log/apache2/error.log

FAQ

Is ISPConfig free?

Yes. ISPConfig 3 is open-source under the BSD license and free for unlimited clients, domains, mailboxes, and servers. The maintainers sell optional commercial products - a migration toolkit from cPanel and Plesk, a detailed manual, and a billing module - but the panel itself is free forever. No phone home, no license key.

What is the difference between ISPConfig and cPanel?

The largest differences are cost and architecture. cPanel is a paid commercial product with a license fee of roughly USD 17-30 per server per month, and it assumes a single-server deployment by default (multi-server is an upsold tier). ISPConfig is free, open-source, and was built from day one around multi-server orchestration. cPanel's end-user UX is more polished and has a larger marketplace of one-click app installers. ISPConfig trades that polish for zero license cost, full root control, and native scaling to dedicated mail, web, DNS, and database nodes.

Can I migrate from cPanel to ISPConfig?

Yes. ISPConfig publishes a commercial migration toolkit that imports cPanel and Plesk backups including websites, databases, mailboxes, DNS zones, FTP accounts, and SSL certificates. For small installs with a handful of sites, manual recreation through the ISPConfig UI plus rsync of document roots and mysqldump of databases works fine. For larger migrations the toolkit is worth the one-time cost because it preserves cron jobs, email filters, and quota settings that are tedious to redo by hand. See our WHMCS migration patterns for adjacent workflows.

What resources does ISPConfig need?

A single-server install with the full mail filtering stack (Amavis plus ClamAV plus SpamAssassin) needs 4 GB RAM, 2 vCPU, and 40 GB disk at absolute minimum. ClamAV alone loads 3-4 GB of signatures into memory at startup, and Amavis forks Perl workers that each consume 100-200 MB. For production hosting of 15-30 active sites with live mail traffic, plan for 6 vCPU and 12 GB RAM on a CloudCore Professional plan. Multi-server setups split these requirements across dedicated nodes: a web node can get by on 4 GB, a mail node wants 8 GB minimum, and a DB node scales with customer database size.

Does ISPConfig support Let's Encrypt?

Yes, natively via acme.sh since version 3.2. Enable it per site with a single checkbox in the Sites module and the panel handles issuance, installation, and renewal automatically. The panel itself also gets a Let's Encrypt certificate during the auto-installer run if the FQDN is publicly resolvable. Renewals run via cron twice daily and reload Apache, Nginx, Postfix, and Dovecot when new certs are installed.

Can ISPConfig run on a low-cost VPS?

ISPConfig runs on VPS plans from 4 GB RAM upward, but you will feel the pinch with ClamAV and Amavis enabled. A 2 GB plan can run the panel with mail disabled, but that defeats one of the core reasons to use ISPConfig. CloudCore Professional at EUR 19.99 per month delivers the 6 vCPU and 12 GB RAM headroom that a single-server install with mail filtering really needs, and leaves room for 20-30 active customer sites. If you are budget-constrained, consider swapping Amavis plus ClamAV for rspamd, which uses roughly a third of the memory for equivalent protection.

Can I run ISPConfig alongside Docker?

Yes, but carefully. The panel manages ports 80, 443, 25, 465, 587, 110, 143, 993, 995, 53, 21, 20, and 8080 on the host. If you run Docker containers that also want those ports, bind them to a different interface or a non-standard host port. The safest pattern is to run ISPConfig on the host and expose Docker services behind ISPConfig's Apache or Nginx via a reverse proxy vhost configured in the panel.

Does ISPConfig have an API?

Yes. ISPConfig exposes a JSON-RPC API and a newer REST API covering essentially every action in the UI - creating clients, sites, mailboxes, DNS records, databases, FTP users, and cron jobs. The API is documented in the official manual and is the standard way to integrate ISPConfig with billing systems like WHMCS, Blesta, or Invoice Ninja. Create a Remote User under System -> Remote Users and grant the specific function groups the integration needs.

Next Steps

Now that ISPConfig is running on your VPS, here are recommended next steps to build on your setup:

• Compare other panels - evaluate HestiaCP for a simpler single-server experience, CyberPanel for OpenLiteSpeed performance, or Plesk if you need a commercial extension ecosystem.
• Add a monitoring stack - deploy Prometheus, Grafana, and node_exporter with our monitoring stack guide to track ISPConfig server health, mail queue depth, and SSL expiry.
• Automate with the ISPConfig API - generate API keys under System -> Remote Users and script customer provisioning. See the official API reference for function lists.
• Harden mail deliverability - publish SPF, DKIM, and DMARC records for every hosted domain, set up reverse DNS (PTR) at your provider, and submit your IP to mail-tester.com to catch spam-score issues.
• Build a redundant DNS cluster - join a second Ubuntu VPS as a DNS mirror to ISPConfig, then publish ns1.yourhost.com and ns2.yourhost.com as customer-facing nameservers.
• Scale to multi-server - when the single box nears capacity, add dedicated mail and database nodes via the flow in Step 12 and migrate customers incrementally.

Skip the Manual Install - Get a Pre-Sized Hosting VPS

Our CloudCore Professional VPS is sized exactly for ISPConfig's full mail-filtering stack, so you can run the auto-installer in this guide end-to-end without hitting memory ceilings.

- 6 vCPU cores and 12 GB RAM - enough for ClamAV plus Amavis plus 20-30 active sites

- 100 GB NVMe SSD - fits customer sites, mailboxes, and a 30-day backup rotation

- Unmetered bandwidth - no surprise traffic bills when a site goes viral

- Instant provisioning - Ubuntu 24.04 ready for SSH in under 60 seconds

- Optional private networking for multi-server ISPConfig clusters

Deploy Your Hosting VPS Now - Plans start at EUR 19.99/month.

For the authoritative reference on every ISPConfig module, flag, and API call, see the official ISPConfig documentation.