Ubuntu IPv6
/etc/netplan/
It includes IPv4 and IPv6 configurations.
network:
version: 2
renderer: networkd
ethernets:
eth0:
dhcp4: false
dhcp6: false
accept-ra: true
addresses:
- 10.10.10.9/24
- 2601:402:8200:xxxx:xxxx:xxxx:xxxx:xxxx/64
# ether xx:xx:xx:xx:xx:xx
nameservers:
addresses:
- 10.10.10.1
- 2601:402:8200:xxxx:xxxx:xxxx:xxxx:xxxx
search: [scsiraidguru.xxx]
routes:
- to: default
via: 10.10.10.1
- to: default
via: 2601:402:8200:xxxx:xxxx:xxxx:xxxx:xxxx
metric: 1
on-link: true ip -6 route show
2600:1700:b101:808f::/64 dev eth1 proto kernel metric 256 pref medium
fe80::/64 dev eth1 proto kernel metric 256 pref medium
default via 2600:1700:b101:808f:94f3:92ff:fe55:8f94 dev eth1 proto static metric 1 onlink pref medium
ip -6 addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 state UNKNOWN qlen 1000
inet6 ::1/128 scope host noprefixroute
valid_lft forever preferred_lft forever
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 state UP qlen 1000
inet6 2600:1700:b101:808f:215:5dff:fe0a:eb0b/64 scope global
valid_lft forever preferred_lft forever
inet6 fe80::215:5dff:fe0a:eb0b/64 scope link
valid_lft forever preferred_lft forever
Enabling IPv6 in Ubuntu 24.04
sudo sysctl -w net.ipv6.conf.all.disable_ipv6=0
sudo sysctl -w net.ipv6.conf.default.disable_ipv6=0
sudo sysctl -w net.ipv6.conf.lo.disable_ipv6=0
Sets the name servers for
/etc/systemd$ sudo mkdir resolved.conf.d
/etc/systemd/resolved.conf.d$
sudo vim head
nameserver: 10.10.10.1
nameserver: 2601:402:8200:8736:94f3:92ff:fe55:8f9a
sudo vim ipv6.conf
[Resolve]
DNSStubListenerExtra=[::1]:53
sudo systemctl restart systemd-resolved
sudo netstat -ulpn | grep :53
udp6 0 0 ::1:53 :::*
udp 0 0 127.0.0.54:53 0.0.0.0:*
/etc/systemd$ sudo vim resolved.conf
[Resolve]
# Some examples of DNS servers which may be used for DNS= and FallbackDNS=:
# Cloudflare: 1.1.1.1#cloudflare-dns.com 1.0.0.1#cloudflare-dns.com 2606:4700:4700::1111#cloudflare-dns.com 2606:4700:4700::1001#cloudflare-dns.com
# Google: 8.8.8.8#dns.google 8.8.4.4#dns.google 2001:4860:4860::8888#dns.google 2001:4860:4860::8844#dns.google
# Quad9: 9.9.9.9#dns.quad9.net 149.112.112.112#dns.quad9.net 2620:fe::fe#dns.quad9.net 2620:fe::9#dns.quad9.net
DNS=10.10.10.1 2601:402:8200:8736:94f3:92ff:fe55:8f9a
#FallbackDNS=
#Domains=
DNSSEC=yes
DNSOverTLS=yes
#MulticastDNS=no
#LLMNR=no
#Cache=no-negative
#CacheFromLocalhost=no
DNSStubListener=no
systemctl restart systemd-resolved
nslookup google.com
Server: 10.10.10.1
Address: 10.10.10.1#53
Non-authoritative answer:
Name: google.com
Address: 142.250.189.110
Name: google.com
Address: 2607:f8b0:4009:816::200e
This is testing IPv4 and IPv6 DNS for UDP, TPC, and TLS.
dig AAAA @2601:402:8200:8736:94f3:92ff:fe55:8f9a google.com
; <<>> DiG 9.18.39-0ubuntu0.24.04.3-Ubuntu <<>> AAAA @2601:402:8200:8736:94f3:92ff:fe55:8f9a google.com
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 34113
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;google.com. IN AAAA
;; ANSWER SECTION:
google.com. 156 IN AAAA 2607:f8b0:4009:816::200e
;; Query time: 1 msec
;; SERVER: 2601:402:8200:8736:94f3:92ff:fe55:8f9a#53(2601:402:8200:8736:94f3:92ff:fe55:8f9a) (UDP)
;; WHEN: Sun May 03 22:36:49 UTC 2026
;; MSG SIZE rcvd: 56
dig AAAA @2601:402:8200:8736:94f3:92ff:fe55:8f9a google.com +tcp
; <<>> DiG 9.18.39-0ubuntu0.24.04.3-Ubuntu <<>> AAAA @2601:402:8200:8736:94f3:92ff:fe55:8f9a google.com +tcp
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 34121
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;google.com. IN AAAA
;; ANSWER SECTION:
google.com. 136 IN AAAA 2607:f8b0:4009:816::200e
;; Query time: 0 msec
;; SERVER: 2601:402:8200:8736:94f3:92ff:fe55:8f9a#53(2601:402:8200:8736:94f3:92ff:fe55:8f9a) (TCP)
;; WHEN: Sun May 03 22:37:10 UTC 2026
;; MSG SIZE rcvd: 56
dig -4 google.com A
; <<>> DiG 9.18.39-0ubuntu0.24.04.3-Ubuntu <<>> -4 google.com A
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 28997
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
; PAD: (409 bytes)
;; QUESTION SECTION:
;google.com. IN A
;; ANSWER SECTION:
google.com. 150 IN A 142.251.210.110
;; Query time: 15 msec
;; SERVER: 10.10.10.1#53(10.10.10.1) (UDP)
;; WHEN: Sun May 03 22:37:31 UTC 2026
;; MSG SIZE rcvd: 468
dig -4 google.com A +tcp
; <<>> DiG 9.18.39-0ubuntu0.24.04.3-Ubuntu <<>> -4 google.com A +tcp
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 64
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
; PAD: (409 bytes)
;; QUESTION SECTION:
;google.com. IN A
;; ANSWER SECTION:
google.com. 128 IN A 142.251.210.110
;; Query time: 1 msec
;; SERVER: 10.10.10.1#53(10.10.10.1) (TCP)
;; WHEN: Sun May 03 22:37:53 UTC 2026
;; MSG SIZE rcvd: 468
dig @10.10.10.1 +tls google.com
; <<>> DiG 9.18.39-0ubuntu0.24.04.3-Ubuntu <<>> @10.10.10.1 +tls google.com
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 10940
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
; PAD: (409 bytes)
;; QUESTION SECTION:
;google.com. IN A
;; ANSWER SECTION:
google.com. 92 IN A 142.251.210.110
;; Query time: 33 msec
;; SERVER: 10.10.10.1#853(10.10.10.1) (TLS)
;; WHEN: Sun May 03 22:38:29 UTC 2026
;; MSG SIZE rcvd: 468
dig @2601:402:8200:8736:94f3:92ff:fe55:8f9a +tls google.com
; <<>> DiG 9.18.39-0ubuntu0.24.04.3-Ubuntu <<>> @2601:402:8200:8736:94f3:92ff:fe55:8f9a +tls google.com
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 43267
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
; PAD: (409 bytes)
;; QUESTION SECTION:
;google.com. IN A
;; ANSWER SECTION:
google.com. 62 IN A 142.251.210.110
;; Query time: 41 msec
;; SERVER: 2601:402:8200:8736:94f3:92ff:fe55:8f9a#853(2601:402:8200:8736:94f3:92ff:fe55:8f9a) (TLS)
;; WHEN: Sun May 03 22:38:59 UTC 2026
;; MSG SIZE rcvd: 468
dig @2601:402:8200:8736:94f3:92ff:fe55:8f9a +tls AAAA google.com
; <<>> DiG 9.18.39-0ubuntu0.24.04.3-Ubuntu <<>> @2601:402:8200:8736:94f3:92ff:fe55:8f9a +tls AAAA google.com
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 11159
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
; PAD: (313 bytes)
;; QUESTION SECTION:
;google.com. IN AAAA
;; ANSWER SECTION:
google.com. 164 IN AAAA 2607:f8b0:4023:2c03::65
google.com. 164 IN AAAA 2607:f8b0:4023:2c03::71
google.com. 164 IN AAAA 2607:f8b0:4023:2c03::8a
google.com. 164 IN AAAA 2607:f8b0:4023:2c03::66
;; Query time: 51 msec
;; SERVER: 2601:402:8200:8736:94f3:92ff:fe55:8f9a#853(2601:402:8200:8736:94f3:92ff:fe55:8f9a) (TLS)
;; WHEN: Sun May 03 22:39:39 UTC 2026
;; MSG SIZE rcvd: 468