this post was submitted on 24 Jun 2024
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[–] [email protected] 114 points 4 months ago (4 children)

Actually, the Dutch government has mandated that all of its services need to be IPv6 compatible.

The longer you try to avoid IPv6, the harder you'll make your life when you eventually need to use it.

It's really not that hard, especially compared to the kludge of protocols that make up IPv4. I know change is scary and difficult, but if you can do IPv4, you can do IPv6.

[–] [email protected] 45 points 4 months ago (3 children)

My ISP doesn't support IPv6, now what?

It's really bullshit.

[–] [email protected] 22 points 4 months ago (1 children)

Hurricane Electric have a free tunnel broker that is super simple to set up if you really want to get on the bandwagon.

https://tunnelbroker.net/

Though honestly I'd say the benefits of setting it up aren't really worth the trouble unless you're keen.

[–] [email protected] 5 points 4 months ago (5 children)

Yeah it's a huge source of problems. If you are outside the US your IPv6 prefix is never gonna be correct in every GeoIP database, even if you send a request to have it corrected, so you sometimes get geoblocked and other sites just block you because it sometimes gets classified as VPN.

[–] [email protected] 8 points 4 months ago* (last edited 4 months ago)

I agree. GeoIP was never a good idea, but here we are. Any ASN could be broken up and routed wherever (and changed) but it's still far too prevalent.

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[–] [email protected] 17 points 4 months ago (1 children)

Hurricane Electric will give you a bunch of free /64s and a /48 to play with, which you can set up for tunneling on any IPv4 connection that doesn't block ICMP traffic to HE. You can set this up within a range of routers, but if your router doesn't support it, you can also set it up on most PCs (Windows and Linux for sure, for macOS you'll need to check, but I'm sure it'll be fine).

You can also use IPv6 locally by simply advertising a subnet from the right range (an ULA), which is also useful for maintaining internal addressing if you do get normal IPv6 but your ISP is a bunch of dickwads that rotate the subnets they hand out (likely to happen if they make you pay extra for a static IP right now).

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[–] [email protected] 10 points 4 months ago (3 children)

It also means you no longer need the kludge that is NAT. Full E2E connectivity is really nice -- though I've found some network admins dislike this idea because they're so used to thinking about it differently or (mistakenly) think it adds to their security.

[–] [email protected] 16 points 4 months ago (3 children)

NAT still has its place in obfuscating the internal network. Also, it's easier to think about firewall/routing when you segregate a network behind a router on its own subnet, IMO.

[–] [email protected] 10 points 4 months ago (1 children)

Given how large the address space is, it's super easy to segregate out your networks to the nth degree and apply proper firewall rules.

There's no reason your clients can't have public, world routeable IPs as well as security.

Security via obfuscation isn't security. It's a crutch.

[–] [email protected] 9 points 4 months ago* (last edited 4 months ago) (1 children)

There's no reason your clients can't have public, world routeable IPs as well as security.

There are a lot of valid reasons, other than security, for why you wouldn't want that though. You don't necessarily want to allow any client's activity to be traceable on an individual level, nor do you want to allow people to do things like count the number of clients at a particular location. Information like that is just unnecessary to expose, even if hiding it doesn't make anything more secure per se.

[–] [email protected] 12 points 4 months ago

Well good news. Because ipv6 has a thing called privacy extensions which has been switched on by default on every device I've used.

That generates random ipv6 addresses (which are regularly rotated) that are used for outgoing connections. Your router should block incoming connections to those ips but the os will too. The proper permanent ip address isn't used for outgoing connections and the address space allocated to each user makes a brute force scan more prohibitive than scanning the whole Ipv4 Internet.

So I'm going to say that using routable ipv6 addresses with privacy extensions is more secure than a single Ipv4 Nat address with dnat.

[–] [email protected] 6 points 4 months ago

That's what temporary privacy addresses are for. Clients can just keep generating new addresses in your /64, which is it's own subnet.

[–] [email protected] 6 points 4 months ago (3 children)

Obfuscation is not security, and not having IPv6 causes other issues. Including some security/privacy ones.

There is no problem having a border firewall in IPv6. NAT does not help that situation at all.

[–] [email protected] 6 points 4 months ago (3 children)

Obfuscation is not security

Yes, of course. But saying trite things like that doesn't get around the idea that giving out a map of the internal network by default isn't the best policy.

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[–] [email protected] 4 points 4 months ago

I think you'll find some ISPs will be reluctant to let go of CGNAT - they're doing quite nicely by charging extra for 'commercial' services where it's not in the way.

Fortunately, many of us know about cloudflare tunnelling and other services, so NAT really isn't a problem to self hosters and even SMEs any more.

[–] [email protected] 3 points 4 months ago (3 children)

Why do you say NAT doesn't make a network more secure?

[–] [email protected] 8 points 4 months ago (2 children)

This article is biased to selling you more F5 equipment but is a reasonable summary:

https://www.f5.com/resources/white-papers/the-myth-of-network-address-translation-as-security

Long story short is that NAT is eggshell security and you should be relying on actual firewall rules (I wouldn't recommend F5) instead of the implicit but not very good protections of NAT.

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[–] [email protected] 6 points 4 months ago (11 children)

It wasn't designed for a security purpose in the first place. So turn the question around: why does NAT make a network more secure at all?

The answer is that it doesn't. Firewalls work fine without NAT. Better, in fact, because NAT itself is a complication firewalls have to deal with, and complications are the enemy of security. The benefits of obfuscating hosts behind the firewall is speculative and doesn't outweigh other benefits of end to end addressing.

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[–] [email protected] 6 points 4 months ago (1 children)

Unless you've gone out of your way to disable the H.263 NAT ALG, NAT actually allows websites and other services to open either random ports on your machine (if using business firewalls) or ports on any device on your network (many consumer routers).

If your router allows you to disable SIP ALG and H.263 ALG, you should. If it doesn't, well, maybe they've been patched? If you've applied a kernel firmware update to your router the last 1-2 years you may be safe (though not many vendors will bother updating the kernel when updating their routers). You'll lose access to SIP phones and some video calling services over IPv4, but at least some Javascript on a random blog won't be able to hack your printer.

This wouldn't work with IPv6, as these two protocols just work with IPv6 (and IPv4, as it was designed). ALGs are hacks around protocols, rewriting packets to make all of the problems NAT causes go away.

More info on this here: https://www.armis.com/research/nat-slipstreaming-v2-0/

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[–] [email protected] 8 points 4 months ago (2 children)

I had network speed issues and the solution was literally to disable ipv6... Fiber 1gbit network still had issues. https://www.reddit.com/r/youtube/comments/owbjdl/anyone_else_getting_buffering_when_using_ipv6/

[–] [email protected] 32 points 4 months ago (1 children)

This has nothing to do with IPv6 itself. I pull in 4K YouTube videos over IPv6 just fine. My IPv6 routes actually have lower latency than my IPv4 routes, funnily enough.

Sounds like your ISP has broken their IPv6 routes, or your modem is outdated and can't do IPv6 hardware acceleration. Disabling IPv6 to downgrade your connection will work as a workaround, at least until your ISP switches over to something using IPv6 as the connection backbone (like DS-Lite, which would allow your ISP to significantly reduce their IPv4 space and make a quick profit selling off their allocations, which is unfortunately becoming more and more common).

Your ISP or modem manufacturer needs to fix the actual problem here.

[–] [email protected] 3 points 4 months ago

4k was fine until I tried watching 8k 60fps HDR on YouTube, disabling IPv6 fixed it. It was weird because speedtest and torrents were completely fine using full bandwidth, just YouTube needed me to disable ipv6

[–] [email protected] 9 points 4 months ago (1 children)

Weird. Ipv6 and YouTube stats for nerds shows between 140mbit and 600mbit depending on what's being watched and the time of day.

Is it possible your isp has problems with their ipv6 setup?

IPv6 overheads should only have a marginal impact on max speeds.

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[–] [email protected] 3 points 4 months ago (2 children)

ipv6 in companies... ipv6 is not hard, but for internal networking no company (really) "needs" more than rfc1918 address space. thus any decision in that direction is always "less" needed than any bonus for (da)magement personnel is crucial for the whole companies survival...

for companies services to be reachable from outside/ipv6 mostly "only" the loadbalancers/revproxies etc need to be ipv6 ready but ... this i.e. also produces logs that possibly break decades old regexes that no one understands any more (as the good engineers left due to too many boni payed to damagement personnel) while other access/deny rules that could break or worse let through where they should block (remember that 192.168. could the local part of ipv6 IF sone genious used a matching mech that treats the dot "." as a wildcard as overpayed damagement personnel made them rush too fast), could be hidden "somewhere". altogether technical debt is a huge blocker for everything, especially company growth, and if no customer "demands" ipv6, then it stays on the damagement personnels list as "fulfilling the whishes of engineers to keep them happy" instead of on the always deleted "cleaning up technical debt caused by damagement personnel" list.

setting up firewalls for ipv6 is quite easy and if you go the finegrained "whitelisted or drop/block" approach from the beginning it might take a bit for ipv6 specials to be known to you, but the much bigger thing is IMHO the then current state of firewall rules. and who knows every existing rule? what rules should be removed already and must not be ported to ipv6? usually firewalls and their rules are a big mess due to ... again too many boni payed to damagement personnel, hindering the company from the needed steps forward...

ipv6 adoption is slow for reasons that are driving huge cars that in turn speed up other problems ;-|

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[–] [email protected] 83 points 4 months ago (7 children)

I also know that I cannot tell the difference between two IPv6 addresses because they all merge into an indiscernible blur inside my head

[–] [email protected] 59 points 4 months ago

Back when we had to dial ipv4 addresses from memory

rotary phone with acoustic coupler

[–] [email protected] 15 points 4 months ago

However I can see when any IPv6 begins with 2a02:12xx:: then it's Swisscom (biggest swiss ISP). But I can't remember any of their hundreds of IPv4 prefixes.

[–] [email protected] 13 points 4 months ago

I have a feeling making it all CAPS would have made it just a bit easier.
That, or using monospace fonts for it everywhere.

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[–] [email protected] 43 points 4 months ago* (last edited 4 months ago) (1 children)

::1 is the new 127.0.0.1
:: abbreviates empty fields
ipv6 has more addresses
there is something going on with mac addresses (asside from arp)

thats all i remember

[–] [email protected] 34 points 4 months ago (1 children)
[–] [email protected] 11 points 4 months ago* (last edited 4 months ago) (9 children)

~~fc00::/7 are ULA (basically what RFC1918 was for IPv4)~~ not entirely true, fc00::/8 is part of ULA, but it is not yet defined. Use fd00::/8 instead.
2001:db8::/32 is for documentation purposes

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[–] [email protected] 26 points 4 months ago (1 children)

I keep hearing this, and I KNOW it's true at the enterprise level, but I've been running my home LAN IPv6 native for the last - 6+ years? Ever since I learned Comcat would vend it to you from their stock router.

Works great. No problems. Didn't used to be that way, but these days most (more?) of the stack bugs have been shaken out.

[–] [email protected] 7 points 4 months ago (1 children)

I'm a network engineer and I run ipv6 natively in all of our datacenters. There are even a handful of end systems that have ipv6 native networking stacks with ipv4 sockets for our non-ipv6 compatible applications. IPv6 issues are basically self-inflicted at this point by companies that see their IT systems as cost centers, or by basilisk directors who's knowledge stopped in the 90's.

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[–] [email protected] 21 points 4 months ago

I am hosting a few services on my LAN over IPv6, except for Plex, which I am tunneling through IPv4, since Plex itself used to have issues with IPv6.

It's always funny when friends complain that one of my services is down, it was 100% IPv6 not working/enabled/willingly disabled on their site yet.

[–] [email protected] 18 points 4 months ago

I made an effort to learn it. In 2000. Again in 2012 or whenever the last big push was. If past is prologue, I may need to learn it again soon. 😆

[–] [email protected] 10 points 4 months ago (2 children)

Ah, Dutch directness... Nothing says clear communication louder than the Dutch

[–] [email protected] 17 points 4 months ago (1 children)

It's an edited image, but you are darn right. Proper communication is great

[–] [email protected] 7 points 4 months ago* (last edited 4 months ago) (1 children)

It is in the style of the original, where during Covid the page on “Migrating to the Netherlands” simply just started with “Do not migrate to the Netherlands”, before expanding on the Covid restrictions on place and what foreign nationals currently in the Netherlands are to do.

On one hand: Now that's loud & clear communication. On the other hand, “Just don't” really ties in to the stereotype of Dutch directness/rudeness.

[–] [email protected] 3 points 4 months ago

Being direct is not rude, in my opinion. I don't know why people need things so sugarcoated. Being direct, to me, is a sign of respect

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