ipv6 [Wiki]

In most cases, you should not need to adjust these files. Instances are normally configured using DHCP. You only really need to change these files if you are trying to enable additional IPs.

Note: Changing to the examples below will cause problems if you take a snapshot of an instance and restore it on a VPS. We recommend reverting back to DHCP before taking a snapshot. Again, keep in mind that these are EXAMPLES only. Using this WILL break your VPS or Dedicated Server. Change the IPs to your assigned IPs and you'll be good to go.

CentOS / RHEL

Your IP configuration should be something similar to

/etc/sysconfig/network-scripts/ifcfg-eth0

It should contain the following, or at least something similar to ensure things work well

DEVICE=eth0
ONBOOT=yes
BOOTPROTO=static
IPADDR=45.63.69.155
NETMASK=255.255.254.0
GATEWAY=45.63.68.1
DNS1=8.8.8.8

IPV6INIT=yes
IPV6_DEFAULTGW=2605:f700:0080:040e::1
IPV6ADDR=2605:f700:80:040e::d7d6:f6a1/64
IPV6_AUTOCONF="yes"
DNS2=2001:4860:4860::8888

For additional IPs and gateways not in your initial IP assignment, they should be added as follows, keeping in mind they're examples only:

IPADDR1="192.168.1.151"
IPADDR2="192.168.2.152"
GATEWAY1="192.168.1.1"
GATEWAY2="192.168.2.1"

/etc/sysconfig/network-scripts/route-eth0

169.254.0.0/16 dev eth0

/etc/sysconfig/network-scripts/ifcfg-eth1

DEVICE=eth1
ONBOOT=yes
BOOTPROTO=static
IPADDR=10.99.0.11
NETMASK=255.255.0.0
MTU=1450

Debian 7+ / Ubuntu 12.xx - 15.xx

/etc/network/interfaces

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
address 45.63.69.155
netmask 255.255.254.0
gateway 45.63.68.1
dns-nameservers 8.8.8.8
post-up ip route add 169.254.0.0/16 dev eth0

iface eth0 inet6 static
address 2001:19f0:5c00:9426:5400:00ff:fe09:bf41
netmask 64
dns-nameservers 2001:4860:4860::8888

auto eth1
iface eth1 inet static
address 10.99.0.11
netmask 255.255.0.0
mtu 1450

Ubuntu 16.xx+

/etc/network/interfaces

auto lo
iface lo inet loopback

auto ens3
iface ens3 inet static
address 45.63.69.155
netmask 255.255.254.0
gateway 45.63.68.1
dns-nameservers 8.8.8.8
post-up ip route add 169.254.0.0/16 dev ens3

iface ens3 inet6 static
address 2001:19f0:5c00:9426:5400:00ff:fe09:bf41
netmask 64
dns-nameservers 2001:4860:4860::8888

auto ens7
iface ens7 inet static
address 10.99.0.11
netmask 255.255.0.0
mtu 1450

FreeBSD

/etc/rc.conf

static_routes="linklocal"
route_linklocal="-net 169.254.0.0/16 -interface vtnet0"
ifconfig_vtnet0="inet 45.63.69.155 netmask 255.255.254.0"
defaultrouter="45.63.68.1"

rtsold_enable="YES"
ipv6_activate_all_interfaces="YES"
rtsold_flags="-aF"
ifconfig_vtnet0_ipv6="inet6 2001:19f0:5c00:9426:5400:00ff:fe09:bf41 prefixlen 64"

ifconfig_vtnet1="inet 10.99.0.11 netmask 255.255.0.0 mtu 1450"

Fedora

/etc/sysconfig/network-scripts/ifcfg-ens3

DEVICE=ens3
ONBOOT=yes
NM_CONTROLLED=no
BOOTPROTO=static
NOZEROCONF=yes
IPADDR=45.63.69.155
NETMASK=255.255.254.0
GATEWAY=45.63.68.1
DNS1=8.8.8.8

IPV6INIT=yes
IPV6ADDR="2001:19f0:5c00:9426:5400:00ff:fe09:bf41/64"
IPV6_AUTOCONF="yes"
DNS2=2001:4860:4860::8888

/etc/sysconfig/network-scripts/route-ens3

169.254.0.0/16 dev ens3

/etc/sysconfig/network-scripts/ifcfg-ens7

DEVICE=ens7
ONBOOT=yes
NM_CONTROLLED=no
BOOTPROTO=static
NOZEROCONF=yes
IPV6INIT=no
IPADDR=10.99.0.11
NETMASK=255.255.0.0
MTU=1450