IPv6: A hosting and developer perspective
Paul Waring
October 8, 2020
Introduction
- Freelance PHP developer and Linux system administrator
- Work on the hosting and development side
- Different challenges to ISP deployment
Why deploy IPv6?
- Not enough IPv4 addresses
- Allocation pools exhausted in many areas
- RIPE 733: You might get a /24 if you’re lucky (waiting list)
- Every VPS, container etc. wants an IP address
- IPv6 fix: more addresses (and a few other shiny things)
Current state of play
- Some hosting providers don’t offer IPv6 at all
- Very few big providers offer IPv6 with feature parity with IPv4
- Facebook/Google: 25-30% of incoming traffic on IPv6 (with wide deployment)
- Alexa top 1000 websites: 25-30% available over IPv6
- Probably need dual-stack for now
Squeezing the last drops from IPv4
- Make the most of the addresses we do have
- HTTP/1.1 - Host: header
- Server Name Indication (broke lots of clients, esp. IE/XP)
- Don’t really work across servers
- Proxy - complicates infrastructure, SPoF
Problems deploying IPv6 (internal, fixable)
- Services not listening on IPv6 (e.g. SSH/firewall)
- Database schema only supports IPv4 addresses
- Application logic assumes IPv4 (e.g. ACLs)
- Monitor both protocols - some software defaults to IPv4
- More things to go wrong
Problems deploying IPv6 (external, not always fixable)
- Third party APIs requiring IPv4 addresses
- Stricter spam detection on email over IPv6
- Proprietary or undocumented applications
- Hardcoded IP addresses
- Lack of feature parity with IPv4 (e.g. no load balancers)
- No immediate benefit for most customers
How can we solve this?
- Technical: Deploy, debug, fix (repeat ad infinitum)
- Policy: Regulatory requirement to deploy IPv6
- Market: IPv6 SEO boost, browser warnings (c.f. HTTPS)
Takeaways
- Deploying IPv6 at the hosting side can be a lot of work
- You will break something
- But you should still do it
- Forget starting a hosting provider (for now)
- Buy
land IPv4, they’re not making it anymore
Thanks for listening
- Slides (+ extra resources): phpdev.uk/talks
- Email: paul@phpdeveloper.org.uk
- Twitter: @pwaring
- Questions?