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Questions tagged [ipv6]

Questions about IPv6, the newest version of the Internet Protocol. This tag should be used when asking about personal/home network IPv6 addressing, or basic IPv6 knowledge. Questions related to company-grade IPv6 networks are off-topic and should be asked on Network engineering SE.

The length of an IPv6 address is 128 bits, compared to 32 bits in IPv4. Therefore the address space supports 2128 or approximately 3.4×1038 addresses. This means that many more devices can be connected directly to the Internet.

A typical IPv6 address would be represented like this:

fe80:0000:0000:0000:0202:b3ff:fe1e:8329

but there are rules for shortening the address such as removing leading zeros:

fe80:0:0:0:202:b3ff:fe1e:8329

or replacing consecutive groups of zeros with a double colon:

fe80::202:b3ff:fe1e:8329

IPv6 on Wikipedia

1331 questions
296
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3 answers

How to connect to a website that has only IPv6 addresses without a domain name?

If a server has only IPv6 addresses without a domain name, how can I connect to the server from my web-browser?
Eonil
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190
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3 answers

Why is there a percent sign '%' in the IPv6 address?

I am using the .NET Framework classes to get the IP addresses for my machine: Dns.GetHostAddresses(Dns.GetHostName()) I have a VirtualBox adapter which has both an IPv4 and IPv6 address. Using the .NET code, I am getting the IPv6 address as…
Amith George
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160
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2 answers

How to avoid exposing my MAC address when using IPv6?

On my Macs, each IPv6 address includes the MAC address of a specific computer (not of my router). Sites such as ipv6-test.com not only show it, but even tell me it belongs to an Apple computer. This feels like a super cookie, and might apply to…
Arjan
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86
votes
7 answers

Is there any benefit to using IPv6 on my home network?

I know that IPv6 is the future because there is only 4 billion IPv4 address, but on a home network, you are not going to have 4 billion users. So are there any other benefits that would make IPv6 on a home network better than using IPv4?
Macha
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79
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3 answers

how to ssh to a ipv6 ubuntu in a LAN?

I'm able to ping my Ubuntu box via command: (where c2h2ttt is listed in /etc/hosts) c2h2@c2h2crawler:~/ttt$ ping6 -I eth1 c2h2ttt PING c2h2ttt(c2h2ttt) from fe80::21b:21ff:fe22:e865 eth1: 56 data bytes 64 bytes from c2h2ttt: icmp_seq=1 ttl=64…
c2h2
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69
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14 answers

How to get the IPv6 IP address in Linux

I have a Linux server and I want to find the main IPv6 address via one single command line. My command so far: $ ip addr show dev eth0 | sed -e's/^.*inet6 \([^ ]*\)\/.*$/\1/;t;d' which…
Ankit Goyal
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56
votes
2 answers

How to force Java to use IPv4 instead IPv6?

My Java browser plug-in is no longer working. When I open a page that has a Java element, Java cannot connect to the server. After investigation, I found that Java was trying to use IPv6, while my network does not support IPv6, so Java always fails…
nyongrand
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56
votes
6 answers

Is IPv6 'faster' than IPv4?

Are there any practical speed/latency gains from using IPv6, or is it just to make room for more IPs?
Jane Panda
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55
votes
3 answers

Why is ARP replaced by NDP in IPv6?

ARP was replaced by the NDP (Neighbour Discovery Protocol). But I don't know the exact reason for this. Are there any security issues in ARP? Why ARP is replaced by NDP? What are the advantages of ARP? Can anyone explain this in simple terms?
Ganeshgm7
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How can I use curl with ::1 for ipv6 based loopback?

I tried a few ways but they seem to be confusing curl. root@testt:~# curl localhost:8080

Hello world!

Boom Bam Splat

root@testt:~# curl ::1:8080 curl: (3) IPv6 numerical address used in URL without brackets root@testt:~# curl…
hak8or
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43
votes
5 answers

IPv4 vs IPv6 priority in Windows 7

I have IPv6 connectivity through Hurricane Electric tunnel. Since IPv6 day this year, many services (google.com, facebook.com, etc.) enabled IPv6 on their main domains. On my Windows machine, IPv6 is preferred over IPv4. This means that whenever I…
haimg
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39
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6 answers

How to disable ipv6 on a specific interface in Linux?

Could someone tell me how to disable ipv6 auto-config on a specific network interface in CentOS? The current situation is: A PC has two network adapters eth0 and eth1 that are connecting to the same LAN, in which, IPv6 router is advertising an IPv6…
Yves Messi
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37
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3 answers

What is the relevance of "fe80::1%lo0 localhost" in /etc/hosts?

Following are the entries in my /etc/hosts. I was wondering what is the last entry (fe80::1%lo0 localhost) for. 127.0.0.1 localhost 255.255.255.255 broadcasthost ::1 localhost fe80::1%lo0 localhost
harish
36
votes
12 answers

Why do I get "General Failure" when pinging host name on a Win 7 node on the network?

This is a very peculiar problem with a station on our network. The client pc is running Windows 7 Pro. What makes this problem interesting is that this client is the only node on the network that seems to be experiencing this proglem. When I try…
Chad Harrison
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33
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7 answers

How to disable autoconfiguration on IPv6 in Linux?

How can I permanently disable autoconfiguration of IPv6 in Linux? When I try to manually delete an address from an interface with: ip -6 addr del 2001:0db8:85a3:0000:0000:8a2e:0370:7334/64 dev eth1 It will reappear a few seconds later, I want it to…
Grumbel
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