The question above for the most part, been reading up on it. Also want to it for learning purposes.
Definitely dual stack if you do. The real benefit of IPv6 is that, supposedly, each of your internal devices can have its own address and be directly accessible, but I don’t think anyone actually wants all of their internal network exposed to the internet. My ISP provides IPv6, but only a single /128 address, so everything still goes through NAT.
Setting it up was definitely a learning process - SLAAC vs DHCP; isc’s dhcpd uses all different keywords for 6 vs 4, you have to run 6 and 4 in separate processes. It’s definitely doable, but I think the main benefit is the knowledge you gain.
Your ISP is doing it wrong, which I guess you already know. I get a /64 net via DHCPv6 for my LAN which is pretty standard.
+1 to dual stack. Too much of the internet is v4 only, missing AAAA, or various other issues. I’ve also had weird issues where a Google/Nest speaker device would fail 50% of the time and other streaming devices act slow/funky. Now I know that means the V6 net is busted and usually I have to manually release/renew. Happens once every few months, but not in a predictable interval.
Security is different, but not worse IMO. It’s just a firewall and router instead of a NAT being added in. A misconfigured firewall or enabling UPnP is still a bad idea with potentially worse consequences.
Privacy OTOH is worse. It used to be that each device included a hardware MAC as part of a statelessly generated address. They fixed that on most devices. Still, each device in your house may end up with a long lived (at least as long as your WAN lease time) unique IP that is exposed to whatever sites you visit. So instead of a unique IP per household with IPv4 and NAT, it’s per network device. Tracking sites can differentiate multiple devices in the house across sites.
This has me thinking I need to investigate more on how often my device IPv6 (or WAN lease subnet) addresses change.
I get a fat /48 network, just in case I need one septillion, two hundred and eight sextillion, nine hundred and twenty-five quintillion, eight hundred and nineteen quadrillion, six hundred and fourteen trillion, six hundred and twenty-nine billion, one hundred and seventy-four million, seven hundred and six thousand and one hundred and seventy-six individual IPs.
IPV6 is pretty wild, we could effectively give every service connecting to every client, in every direction, for every single individual bit its own dedicated address without getting anywhere near using that address space.
And the biggest disadvantage of IPv6 is that each of your internal devices has its own address and can be directly accessible from outside. So you need to completely rethink how you do security.
Isn’t that what tburkhol addressed in their first paragraph? Or are you suggesting further steps than just putting those devices behind NAT? I am not at all trying to be snarky, I actually want to know more about this.
You don’t need to use nat on ipv6. Most routers are based on Linux and there you have conntrack.
With that you can configure by default outgoing only connections just like nat and poke holes in the firewall for the ports you want specifically.
Also windows and I think Linux use ipv6 privacy extensions by default. That means that while you can assign a fixed address and run services, it will assign random ip addresses within your (usually) /64 allocation for outgoing connections. So people can’t identify you and try to connect back to your ip with a port scanner etc.
All the benefits of nat with none of the drawbacks.
And can be identified/tracked individually by outside entities. In IPv4, a website sees both my device and my kid’s device as the same IP. In IPv6 they’re different so this just provides more ways for them to track you.
First of all they use much more than the device IP to identify individual devices. IPv4 is no longer all that useful for identification with things like CGNAT being common.
But with IPv6 they’ll see my device IP, then they’ll see the same device with completely different IP, then again. Same for my kid’s device. But again, all of the above applies. It is a concern, but there are much better ways of tracking you anyways.
That’s the reason for rcf 4941. It randomises the host part of your IPv6 address.
There’s a bunch of advantages. IPv6 can be useful since your devices can have the same IP both internally and externally. No dealing with port forwarding. No split horizon DNS (where you have different DNS entries for internal vs external). No NAT. No DHCP required for client systems (can just use SLAAC to auto-generate addresses). Much simpler routing. It’s a bit faster. Proper QoS.
I used to use Comcast, who actually have very good IPv6 support. They were the first major US ISP to roll out IPv6 to everyone, around 10 years ago. Unfortunately my current ISP doesn’t have IPv6, but they’re aiming to roll it out this year.
A good ISP that supports IPv6 will give you a /64 range. That’s a huge number of IPs, 2^64. Easily enough for every device on your network to have a lot of public IPs. If you use Docker or VMs, you could give each one a public IPv6 address.
When every device on your network can have a public IP, there’s no longer a reason to have private IPs. Instead, you’d use firewall rules for internal-only stuff (ie allow access only if the source IP is in your IPv6 range).
This is how the internet used to work in the old days - universities would have a large IP range, and every computer on campus would have a public IP.
Of course, you’d still have a firewall on your router (and probably on your computers too) that blocks incoming connections for things you don’t want to expose publicly.
A good isp would give you something bigger than a /64 - /56 or /48. something that you can subnet.
For LAN, no. If you have a router NAT’ting traffic and providing DHCP service there’s really no need for ipv6. Almost every ipv6 enabled service provides both 6 and 4 usually and NAT figures it out, and many still provide only 4, meaning you can’t just get rid of ipv4 entirely.
If your ISP has modernized and is actually providing an ipv6 address, I suppose there’s probably a tiny benefit of being able to go ipv6>ipv6 when routing, bust most all devices nowadays can handle NAT translation from ipv4 to ipv6 and vice versa with no routing penalty. I don’t know if there are any ISP’s out there who can provide static ipv6 addresses without a NAT router to your entire LAN though.
If you’re buying a vps or something ipv6 is easier to get a static address for.
That of course leaves the last good reason: why not? If you’re doing homelab hosting stuff why not experiment with ipv6 and fully modernize your network. They suck to type in but it’s fun to know your stuff is brand new and using the “best”.
Depends on how you define “worth it”. Most selfhosting is done not for worth, but for a hobby.
Hobbies are often worthwhile. Maybe not financially, but often psychologically.
It’s good to learn, because it will become more common as time moves on, particularly if you get into the datacenter/cloud/ISP industry. It’s less important for the general home user, but it is important to understand how it works and how to use it safely.
Just treating it like IPV4 with more address space is dangerous though. you need to think differently about security and firewalls as it is as if every device has its own dedicated WAN address and could be open to the internet without you knowing.
Indeed it is good to learn: ipv6.he.net/certification is a free course everybody should take the first 2-3 levels of.
The login credentials you create for that website will allow you to login to their sister site tunnelbroker.net and claim a /48 delegation for your DDNS tunnel, also free, to promote the changeover to v6 from v4, especially for people with dynamic WAN IPS from their ISP and no IPv6.
Can confirm that HE course is good. They’ve even sent me a free t-shirt after I’ve completed it.
