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IPv6 adoption continues to grow, and many VPS providers now offer IPv6 addresses alongside IPv4. This guide covers configuring IPv6 correctly on your server for dual-stack operation.

Why IPv6 Matters

• IPv4 address exhaustion makes IPv6 increasingly important for future-proofing
• Some networks/ISPs are IPv6-preferred or IPv6-only, and having both ensures maximum reachability
• Often provided free alongside IPv4 by hosting providers, with no reason not to enable it

Step 1 — Check Whether Your VPS Has an IPv6 Address Assigned

ip -6 addr show

If nothing appears, check your hosting provider's control panel — IPv6 may need to be explicitly enabled/assigned for your instance.

Step 2 — Configure the IPv6 Address (If Not Automatic)

sudo nano /etc/netplan/50-cloud-init.yaml

network:
  ethernets:
    eth0:
      addresses:
        - 2001:db8::2/64
      gateway6: 2001:db8::1
      nameservers:
        addresses: [2606:4700:4700::1111]

Use the exact IPv6 address, prefix, and gateway values provided by your hosting provider.

sudo netplan apply

Step 3 — Verify Connectivity

ping6 google.com

Step 4 — Add an AAAA DNS Record

In your domain's DNS settings, add an AAAA record pointing to your VPS's IPv6 address, alongside the existing A record for IPv4 — see How to Point a Domain to Your VPS (A/AAAA Records).

Step 5 — Configure Nginx/Apache to Listen on IPv6

server {
    listen 80;
    listen [::]:80;
    listen 443 ssl;
    listen [::]:443 ssl;
    server_name yourdomain.com;
}

The [::]: syntax specifies the IPv6 wildcard address — without this, your web server only accepts IPv4 connections even if the DNS AAAA record exists.

Step 6 — Configure the Firewall for IPv6

UFW automatically applies most rules to both IPv4 and IPv6 if IPV6=yes is set in /etc/default/ufw (the default in most modern distributions) — verify this:

sudo cat /etc/default/ufw | grep IPV6

Testing IPv6 Access to Your Website

curl -6 https://yourdomain.com

Or use an online IPv6 connectivity checker to confirm your site is reachable over IPv6 from the public internet.

Common Errors

Site unreachable over IPv6 despite AAAA record — verify the web server is explicitly listening on [::], not just the IPv4 wildcard.

IPv6 configured but no connectivity — verify the gateway address and prefix length exactly match what your provider specified; a small typo in IPv6 addressing is a very common cause of connectivity failure.

Best Practices

• Enable IPv6 if your provider offers it at no additional cost — there's little downside
• Ensure firewall rules apply consistently to both IPv4 and IPv6
• Test connectivity explicitly over IPv6, don't assume dual-stack works just because IPv4 does

Continue Reading

• How to Point a Domain to Your VPS (A/AAAA Records)
• How to Configure UFW (Uncomplicated Firewall) on Ubuntu & Debian
• DNS Records Explained: A, AAAA, CNAME, MX, TXT & More

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