Difference between revisions of "IPv6"
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− | + | ;https://ifconfig.co/ | |
+ | :Including CLI-support | ||
;https://test-ipv6.com/ | ;https://test-ipv6.com/ | ||
;https://ipv6-test.com/ | ;https://ipv6-test.com/ | ||
:Check your IPv6 configuration | :Check your IPv6 configuration | ||
+ | ;http://ipv6-test.com/validate.php | ||
+ | :Check IPv6 support for websites | ||
+ | |||
+ | |||
+ | ==Address Assignment== | ||
+ | |||
+ | The [http://www.iana.org/assignments/ipv6-address-space IPv6 address assignment] is handled by IANA. Most important prefixes are: | ||
+ | <table class="plain"> | ||
+ | |||
+ | <tr> | ||
+ | <td>2000::/3</td> | ||
+ | <td>Global Unicast</td> | ||
+ | <td>Global scope</td> | ||
+ | </tr> | ||
+ | <tr> | ||
+ | <td>FC00::/7</td> | ||
+ | <td>Unique Local Unicast</td> | ||
+ | <td>Local Unicast. For intranets, not routed, like IPv4 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. Currently FC00::/8 is undefined, only FD00::/8 is used</td> | ||
+ | </tr> | ||
+ | <tr> | ||
+ | <td>FE80::/10</td> | ||
+ | <td>Link Local Unicast</td> | ||
+ | <td>Link Identification, addresses can be based on the interface MAC address</td> | ||
+ | </tr> | ||
+ | <tr> | ||
+ | <td>FF00::/8</td> | ||
+ | <td>Multicast</td> | ||
+ | <td></td> | ||
+ | </tr> | ||
+ | |||
+ | </table> | ||
+ | |||
+ | ==Local Unicast== | ||
+ | Uses are advised to generate a 40 bits Global ID for their intranets. It is advised to calculate the Global Id using a specified procedure to maximize the probability of an unique address. | ||
+ | |||
+ | [http://tools.ietf.org/html/rfc4193#section-3.2 Local Unicast Address-format] | ||
+ | <table> | ||
+ | <tr> | ||
+ | <th align=left>Prefix</td> | ||
+ | <th align=left>L</th> | ||
+ | <th align=left>Global ID</th> | ||
+ | <th align=left>Subnet ID</th> | ||
+ | <th align=left>Interface ID</th> | ||
+ | </tr> | ||
+ | <tr> | ||
+ | <td>7 bits<br /> | ||
+ | FC00::/7</td> | ||
+ | <td>1 bit<br /> | ||
+ | Locally assigned</td> | ||
+ | <td>40 bits<br /> | ||
+ | User defined</td> | ||
+ | <td>16 bits<br /> | ||
+ | Local subnet</td> | ||
+ | <td>64 bits<br /> | ||
+ | Locally assigned or by dhcp</td> | ||
+ | </tr> | ||
+ | <tr> | ||
+ | <td>1111110</td> | ||
+ | <td>1</td> | ||
+ | <td></td> | ||
+ | <td></td> | ||
+ | <td></td> | ||
+ | </tr> | ||
+ | |||
+ | </table> | ||
+ | The Interface ID is in the so-called ‘Modified EUI-64 Format’. How to go from a MAC address to Modified EUI-64 format is described in appendix A of [href="http://tools.ietf.org/html/rfc4291 RFC 4291].The Routing Advertising Daemon radvd provides ‘Stateless Autoconfiguration’ e.g. by assigning IPv6 addresses and routing information to nodes on the LAN. | ||
+ | |||
+ | |||
==Disable IPv6 on a system== | ==Disable IPv6 on a system== | ||
Line 18: | Line 87: | ||
;cat /proc/sys/net/ipv6/conf/all/disable_ipv6 | ;cat /proc/sys/net/ipv6/conf/all/disable_ipv6 | ||
− | :Check if IPv6 has been disabled | + | :Check if IPv6 has been disabled: |
+ | :0 => IPv6 is not disabled | ||
+ | :1 => IPv6 is disabled | ||
+ | |||
+ | ==Check IPv6 autoconfiguration== | ||
+ | ;<code>cat /proc/sys/net/ipv6/conf/eth0/autoconf</code> | ||
+ | :0 => autoconf is disabled | ||
+ | :1 => autoconf is enabled | ||
+ | |||
+ | ==Misc commands== | ||
+ | |||
+ | ;/sbin/ip -6 addr del <ipv6address>/<prefixlength> dev <interface> | ||
+ | :Remove ipv6 addres from an interface |
Latest revision as of 10:12, 20 December 2020
- https://ifconfig.co/
- Including CLI-support
- https://test-ipv6.com/
- https://ipv6-test.com/
- Check your IPv6 configuration
- http://ipv6-test.com/validate.php
- Check IPv6 support for websites
Address Assignment
The IPv6 address assignment is handled by IANA. Most important prefixes are:
2000::/3 | Global Unicast | Global scope |
FC00::/7 | Unique Local Unicast | Local Unicast. For intranets, not routed, like IPv4 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. Currently FC00::/8 is undefined, only FD00::/8 is used |
FE80::/10 | Link Local Unicast | Link Identification, addresses can be based on the interface MAC address |
FF00::/8 | Multicast |
Local Unicast
Uses are advised to generate a 40 bits Global ID for their intranets. It is advised to calculate the Global Id using a specified procedure to maximize the probability of an unique address.
Prefix | L | Global ID | Subnet ID | Interface ID |
---|---|---|---|---|
7 bits FC00::/7 |
1 bit Locally assigned |
40 bits User defined |
16 bits Local subnet |
64 bits Locally assigned or by dhcp |
1111110 | 1 |
The Interface ID is in the so-called ‘Modified EUI-64 Format’. How to go from a MAC address to Modified EUI-64 format is described in appendix A of [href="http://tools.ietf.org/html/rfc4291 RFC 4291].The Routing Advertising Daemon radvd provides ‘Stateless Autoconfiguration’ e.g. by assigning IPv6 addresses and routing information to nodes on the LAN.
Disable IPv6 on a system
At the end of /etc/sysctl.conf
add:
net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1
- sysctl -p
- Force reload of the kernel parameters as in /etc/sysctl.conf
- cat /proc/sys/net/ipv6/conf/all/disable_ipv6
- Check if IPv6 has been disabled:
- 0 => IPv6 is not disabled
- 1 => IPv6 is disabled
Check IPv6 autoconfiguration
cat /proc/sys/net/ipv6/conf/eth0/autoconf
- 0 => autoconf is disabled
- 1 => autoconf is enabled
Misc commands
- /sbin/ip -6 addr del <ipv6address>/<prefixlength> dev <interface>
- Remove ipv6 addres from an interface