7 votes
Accepted

Why does peer-discovery work for IPv6 but not IPv4?

And the peer-discovery functionality that I've built works by simply sharing the IP address of connected nodes along with their announced port for incoming connections. There are a few issues with ...
u1686_grawity's user avatar
4 votes
Accepted

How to configure VirtualBox NAT network with IPv6?

While it might be in theory possible for VirtualBox's NAT implementation to forward IPv6 connections to an IPv4 host, such protocol translation tends to introduce a lot of complications, such as "...
u1686_grawity's user avatar
4 votes
Accepted

How can I tell ssh to connect using the non-temporary IPv6 address?

On Linux, ssh would need to call setsockopt(IPV6_ADDR_PREFERENCES) to request a specific address type. (This is not mentioned in Linux setsockopt docs, but the code is present in the kernel and seems ...
u1686_grawity's user avatar
4 votes

How to turn on IPv6 on an Amazon EC2 instance?

According to https://aws.amazon.com/blogs/networking-and-content-delivery/dual-stack-ipv6-architectures-for-aws-and-hybrid-networks/: Go to your VPC settings and assign a /56 prefix. Go to subnet ...
u1686_grawity's user avatar
4 votes

Make socat listen on both IPv4 and IPv6 stacks

You can configure socat to listen on both IPv4 and IPv6 by, counter-intuitively, always use the "TCP6-LISTENER" or "UDP6-LISTENER" address forms. This causes socat to listen in a ...
terinjokes's user avatar
3 votes
Accepted

How does one create nftables rule that accepts connections from the same IPv6 subnet, when the IPv6 prefix is dynamic?

The feature doesn't exist ... yet? Currently, nftables can only use one register (in its virtual state machine): it applies bitwise operations on the left hand side (LHS) to compare the result with a ...
A.B's user avatar
  • 5,876
2 votes
Accepted

Ubuntu ipv6 link-local not set

I found that my RPI had addr_gen_mode set to 1, and I was not running network-manager, so nothing setup the address. I restored it to 0 in sysctl.conf, and it worked. This article helped me ...
mcr's user avatar
  • 136
2 votes
Accepted

How to check which IPv6 is being announced in my network on Linux

Use rdisc6 (from "ndisc6") to send a Router Solicitation, which will immediately show the advertisements. # rdisc6 -m wlan0 (The -m option tells rdisc6 to continue waiting after the first ...
u1686_grawity's user avatar
2 votes
Accepted

Set ufw to allow incoming traffic from common IPv6 prefix

While UFW could dynamically update its firewall rules according to the currently received prefix, as far as I know it doesn't have such functionality right now. At the underlying iptables/nftables ...
u1686_grawity's user avatar
2 votes

How can I add an IPv6 address with a scope ID to the ssh config file?

In case you are still trying to do proxy commands on the command line in zsh, here is an example of how to use it with ipv6 addresses ssh -v -o "ProxyCommand sush -W \[%h\]:%p your_jump_server&...
Ob200's user avatar
  • 21
2 votes

Two ULA addresses on one interface

The valid_lft value on the first IPv6 address means it was acquired through a DHCP lease. It shows a /128 mask because it's a single host IP (compare it to /32 in IPv4). ip -6 route should show the /...
Cpt.Whale's user avatar
  • 7,661
1 vote

Minecraft Server doesn't let others connect when running the .jar using java (instead of javaw)

Update: My firewall was messing with java.exe, but not with javaw. Pretty obvious in hindsight. I fixed it by just creating a new rule.
Aze0n's user avatar
  • 11
1 vote
Accepted

How to utilize an IPv6 address on Windows Server for a service

Except in advanced use cases (high availability with failover), software can only bind to local addresses. A local address is an address that is assigned to one of the network interfaces of the ...
Daniel B's user avatar
  • 62.8k
1 vote
Accepted

hide output of nmcli network command

None of that is actually the output of the nmcli command. All four lines are kernel log messages that are being output to the system console ("out of band" if you like) – basically the same ...
u1686_grawity's user avatar
1 vote

How to remote access CCTV's device behind CGNAT for IPv4, and device doesn't have support for DDNS IPv6?

There is more then one way of solving this, but the one I would consider is building a VPN network. I'd start by getting a VM with a cloud provider and running a VPN server on it (I'd choose OpenVPN ...
davidgo's user avatar
  • 70.6k
1 vote

IPv6 and Privacy Extensions in Linux not working as expected with dhcpv6

OK, the problem is solved. Reason was the incorrect ra from my cable box which was setup by my provider, the culprit is: AdvValidLifetime 0; AdvPreferredLifetime 0; which leads to continuos ...
trupf's user avatar
  • 31
1 vote
Accepted

Is using WireGuard keep-alive feature going to create issues when connected for long time?

They certainly can detect it (NAT state tables could easily have a timestamp and often do), but they probably won't bother unless you're using much more than just one port... or unless they're ...
u1686_grawity's user avatar
1 vote
Accepted

Chrome and Edge MDNS/IPv6 operation

Chrome does not query for IPv6 addresses (AAAA records) if it knows that it doesn't have global IPv6 connectivity. As your device doesn't have a global address, that strongly implies the PC doesn't ...
u1686_grawity's user avatar
1 vote
Accepted

Are link-local networks considered "public" by Windows?

"Public" vs "Private" in Windows Firewall doesn't classify IP network prefixes – it classifies the state of the entire network interface. (That is, all traffic from a given network ...
u1686_grawity's user avatar
1 vote

Lag on internet connection in terminal programs

The question is how can I diagnose the problem? First I would suggest to un-disable everything that you tried disabling. Diagnose the problem when the system is in its normal state. Since this looks ...
u1686_grawity's user avatar
1 vote

Why doesn't this /120 ipv6 subnet route?

Answering my own question as I figured out the issue. The VPS provider connects my VPS to a virtual ethernet network and the VPS relies on Network Discovery Protocol to find the router. A similar ...
Jaredo Mills's user avatar
1 vote

`IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready` message repeating every minute

It means the actual Ethernet link is being lost, then re-established, every minute. It's most likely the same issue that caused the earlier network outage – normally I would say either your machine's ...
u1686_grawity's user avatar
1 vote

How to prevent Windows 10 from reverting skipped DHCPv6 IPv6 address? Or how to disable DHCPv6?

I found that I can disable DHCPv6 for a net card by Set-NetIPInterface -Dhcp Disable -InterfaceAlias Wi-Fi -AddressFamily IPv6. After executing that, my net card had only 2 public IPv6 addresses, ...
Hertz Hu's user avatar
1 vote
Accepted

How can a faulty DNS entry in the router's RA cause WiFi disconnections on a phone?

This behavior seems logical from a phone that doesn't give up. As the router was still the source of the internet, the Pixel 6 phone was correctly trying to get IPv6 internet from an IP that however ...
harrymc's user avatar
  • 479k
1 vote

How can I overwrite the default gateway which radvd is advertising

You cannot; the host that issues the Router Advertisement must be the router itself (unlike DHCP, there is no option to send RAs on behalf of another gateway), and per RFC 4861 section 4.2, Router ...
u1686_grawity's user avatar
1 vote

What causes IPv6 ping of linux guest to drop packets in cyclical fashion on Win 10?

TL;DR I unwittingly "booby-trapped" the system in regards to IPv6 connectivity a long time ago by telling the windows firewall to Block all incoming connections on public networks. This ...
T Nierath's user avatar
  • 527
1 vote
Accepted

How do I prevent ipv6 addresses being used in a mixed ipv4 ipv6 environment?

If the Pi is still using an IPv6 address after being rebooted, that means one of two things: Someone configured that address (and gateway) statically. Take a look at the NetworkManager connection ...
u1686_grawity's user avatar
1 vote

IPv6 masquerading on linux

This is likely due to the IPv6 masquerading feature being disabled in your kernel. It is a build-time feature switch: https://www.kernelconfig.io/config_nf_nat_masquerade_ipv6?q=&kernelversion=5....
Christoph Sarnowski's user avatar
1 vote

Force Google Chrome to visit a website with IPv4 (instead of IPv6), possible?

Use nslookup, such as nslookup MySite.com. When used as nslookup google.com, the reply is: Name: google.com Addresses: 2607:f8b0:4009:808::200e 142.250.190.14 So enter https://142....
eewiz's user avatar
  • 11
1 vote

Implementing an OpenVPN "kill switch" with iptables

A short solution Add an empty group tunnel Run OpenVPN within this group (with sg tunnel or Group=tunnel for systemd unit) Use the following rules # Local traffic is allowed iptables -A INPUT -i lo ...
andreoss's user avatar
  • 111

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