IPv4 addresses ran out long ago; IPv6 offers a virtually inexhaustible address space. Many VPS now support "dual stack" (both IPv4 and IPv6) by default. Whether to use IPv6 depends on your workload.

1. Why IPv6 exists

IPv4 has only ~4.3 billion addresses — long insufficient — which keeps dedicated IPv4 getting pricier. IPv6's address count is astronomical, fixing the shortage at the root.

2. Benefits

  • Plentiful and usually free/cheap: many providers hand out large IPv6 blocks.
  • Sometimes better paths: some ISPs have higher-quality IPv6 peering.
  • Future-proof: IPv6 share keeps rising on mobile networks and new devices.

3. How to use it on a VPS

Most VPS are dual stack and assign both IPv4 and IPv6. To make a site IPv6-ready:

  • Add both A (IPv4) and AAAA (IPv6) DNS records.
  • Ensure services (e.g. Nginx) listen on IPv6: listen [::]:80;.
  • Don't forget IPv6 firewall rules (ip6tables / ufw handles it by default).

4. Who needs it

Mobile-facing, overseas, or IPv4-cost-sensitive workloads benefit. IPv6-only is still not universal, so don't drop IPv4 for IPv6-only or some users can't reach you.

5. Watch out

After enabling IPv6, verify your firewall locks down IPv6 ports too — a tight IPv4 but wide-open IPv6 is a common security hole. For dual-stack advice, contact sales @aliyun370.