33
votes
How do I get the pingable IPv6 address of my machine?
Any IPv6 address that starts with fe80: is the equivalent of IPv4 169.254.*.* address, i.e. it's a link-local address, reachable only in the network segment it's directly connected to, using the NIC ...
- 103k
24
votes
Accepted
How can I view IPv6 router advertisements that are being received by my computer for diagnostic purposes?
Using tcpdump which is installed by default on many distributions:
tcpdump -n -i eth0 icmp6
will show you all ICMPv6 packets of which - under usual conditions - almost all are neighbor discovery ...
- 7,633
22
votes
Meanings of ip address notation [::]:[someport]
[::] indicate all ipv6 addresses. 4443 is a port number. So if a service is bound to [::]:4443 it'll be listening to all ipv6 addresses available in your system. It's similar to listening 0.0.0.0 for ...
- 2,128
22
votes
Accepted
How to get Pi-Hole to work with IPv6?
I got it working. Here's what I did:
When I initially set up my Pi-Hole, I only had IPv4 on my system. Thus Pi-Hole only downloaded IPv4-capable blacklists.
So I turned IPv6 on on my home router, and ...
- 2,602
16
votes
Accepted
IPv6 addressing, dynamic prefix static local part
There are two ways to do this. One is the easy way and one is the hard way.
The easy way is to run a DHCPv6 server on your network and assign host addresses to each device yourself. Or let the server ...
- 8,908
15
votes
Accepted
Why does dig -6 google.com not work for me?
-4/-6 tells dig to only use IPv4/IPv6 connectivity to carry your query to the nameserver - it doesn't change whether to query for A records(IPv4) or AAAA records(IPv6) if that's what you intended. If ...
- 1,639
14
votes
How can I view IPv6 router advertisements that are being received by my computer for diagnostic purposes?
While not built in, I find the command-line tool radvdump (part of the radvd package on my distro) very informative as it fully decodes the router advertisements and displays them in detail, including ...
- 7,073
13
votes
Add IPv6 address to existing IPv4 interface not working
Your ifup probably doesn't run because the interface already has the IPv4 address and it can't add it twice. It will not even reach the IPv6 line. If you can you should bring the interface down so all ...
- 1,516
13
votes
Accepted
Is net.ipv6.conf.all.forwarding=1 equivalent to enabling forwarding for all individual interfaces?
Looks like indeed it is designed to work differently compared to IPv4's */forwarding and all/forwarding:
From https://www.kernel.org/doc/Documentation/networking/ip-sysctl.txt:
conf/all/forwarding - ...
- 5,853
13
votes
Accepted
wget uses ipv6 address and takes too long to complete
curl and wget do not use different mechanisms for resolving domains (they're using getaddrinfo()). However, curl implements a fast fallback algorithm to improve the user experience in cases where IPv6 ...
- 694
12
votes
Accepted
Is it possible to implement IPv6 on a virtual interface (eth0:1 interface) in Linux?
IPv4 implementations originally only supported one address per interface, which is why virtual interfaces were invented so you can add multiple addresses on the same physical interface.
IPv6 supports ...
- 1,516
12
votes
Accepted
Enable ipv6 on Debian 10 if there is no /proc/sys/net/ipv6 folder
There are many ways to disable IPv6 in Linux, so you'll have to check for them all.
First, your kernel version does not quite look like Debian 10 standard AMD64 kernel. If you are using a custom ...
- 103k
11
votes
Accepted
How do I get the pingable IPv6 address of my machine?
From man ping6, you must tell ping which interface you are using:
-I interface address
Set source address to specified interface address. Argument may be numeric IP address or name of device. When ...
- 34.4k
11
votes
Accepted
"deprecated" in ip addr sh?
deprecated address is an IPv6 concept described for example in
RFC4862:
deprecated address - An address assigned to an interface whose use is
discouraged, but not forbidden. A deprecated address ...
- 25.7k
11
votes
Accepted
What is this sit0 device?
Based on information I've found in this blog post from Red Hat, I think I understand the purpose. (I'm not a Linux networking expert, so if anyone more knowledgeable sees any mistakes, feel free to ...
- 885
10
votes
Why does dig -6 google.com not work for me?
Yes, that suggests that you do not have IPv6 connectivity.
If you want to obtain an IPv6 address for google rather than using IPv6 to obtain an address for google, you want
dig -t aaaa google.com
...
- 9,065
10
votes
Meanings of ip address notation [::]:[someport]
It's a bind designation to port 4443 of all interfaces that support IPv6. It is equivalent to [0000:0000:0000:0000:0000:0000:0000:0000]:4443.
- 46.1k
10
votes
Accepted
Linux assigns an fe80::/64 address to an interface. Shouldn't that be fe80::/10?
The address space allocated to link-local addresses is fe80::/10, but the next 54 bits are defined to be all zeroes, so the effective range is fe80::/64. Which puts it in line with the usual custom ...
- 142k
10
votes
What is the proper way to display IPv6 Addresses in /etc/hosts
The hosts file format consists of lines, each of which contains the IP address, followed by whitespace, then one or more hostnames, also separated by whitespace.
Nothing changes when the address is ...
- 8,908
10
votes
Accepted
Git push/pull taking too long - IPv6 issue
In order to make this permanent, open your /etc/sysctl.conf file using sudo
sudo nano /etc/sysctl.conf
Add the line at the bottom of the file:
net.ipv6.conf.all.disable_ipv6=1
After that you may ...
- 6,502
9
votes
Accepted
i don't get ipv6. Why cannot I ping ipv6.google.com?
You have only Link-Local, non routable ipv6 (fe80::/10).
So You have no public routable IPv6.
In this configuration You can make ipv6 connect only to Link-Local addresses in same L2 segment.
- 615
9
votes
Accepted
What is the difference between "all", "default" and "eth*" in /proc/sys/net/ipv[46]/conf/?
I'm going to supply a new answer to this question, since many Google search results lead here, and the internet has a lot of outdated information and misinformation about this.
net.ipv{4,6}.conf....
- 20.1k
9
votes
Accepted
does :::80 in netstat output means only ipv6 or ipv6+ipv4?
A listening socket that is bound to ::, i.e. any address IPv6 address (INADDR6_ANY), may or may not also listen to connections using IPv4. This depends from several things:
Some operating systems are ...
- 13.3k
9
votes
Accepted
How can you run OpenVPN client inside a docker container?
I got it working. It looks like I have to enable IPv6 manually:
docker run -it --rm --cap-add=NET_ADMIN --device /dev/net/tun \
--sysctl net.ipv6.conf.all.disable_ipv6=0 -v $PWD:$PWD \
...
- 163
9
votes
Accepted
sshd_config - "Match Address <IPv6>" not matching
After trying just about everything I could think of, I was able to find a solution that worked for me. I wanted to allow password auth to users on my LAN but only allow key based auth from outside the ...
- 106
8
votes
Accepted
Stable IPv6 address on Fedora
On Fedora 25 Workstation, NetworkManager (NM) configures all network interfaces, by default. That means also the wired ones. And the NetworkManager doesn't create EUI-64 derived IPv6 addresses. ...
- 58.2k
8
votes
IPv6 addressing, dynamic prefix static local part
Michael did a very good summary and plugwash's recent tip was the best I could find after hunting for several hours for a CentOS 7/RHEL (also systemd and network manager) solution. After getting used ...
- 81
8
votes
Accepted
Disabling IPv6 on Mint and Debian
One needs to edit the following file:
/etc/sysctl.conf
to add the following lines, preferably to the end of the file:
net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net....
- 29.3k
8
votes
What are the essential iptables rules for IPv6 to work properly?
The essential rules will depend on the network as a network might instead use SLAAC instead of DHCPv6, or there can be other complications depending on tunnels, ICMP handling, etc.
-A INPUT -m ...
- 35.2k
Only top scored, non community-wiki answers of a minimum length are eligible