How to add multiple ipv6 to vps?

Ruriko

I have a NAT VPS running Ubuntu 22.04.3 LTS and OVZ with a ipv6 /64 block.
I'm quite new to ipv6 so I'm having trouble adding multiple ipv6 to my vps since i'm unable to ping the extra ips so these are the steps of what I did:
edit interface with
nano /etc/network/interfaces
then add
up ip -6 address add 2a0a:6040:9718:014f:0000:0000:0000:0001 dev venet0
rebooted the network with
systemctl restart networking
then tested ipv6 with
curl -6 https://ifconfig.co
but it doesn't work
curl: (28) Failed to connect to ifconfig.co port 443: Connection timed out
it works with the main ip 2a0a:6040:9718:14f::a but it doesn't work with the added ips

here's the full interface config

# This configuration file is auto-generated.
# WARNING: Do not edit this file, otherwise your changes will be lost.
# Please edit template /etc/network/interfaces.template instead.

auto lo
iface lo inet loopback

# Auto generated venet0 interfaces
auto venet0
iface venet0 inet static
    address 127.0.0.1
    netmask 255.255.255.255
    broadcast 0.0.0.0
    up route add default dev venet0
auto venet0:0
iface venet0:0 inet static
    address 10.37.50.144
    netmask 255.255.255.0


iface venet0 inet6 static
    address 2a0a:6040:9718:14f::a/64
    up ip -6 r a default dev venet0
        up ip -6 address add 2a0a:6040:9718:014f:0000:0000:0000:0001 dev venet0

Am I missing any other steps to make the extra ipv6 work?

NessaCat

try

iface venet0 inet6 static
    address 2a0a:6040:9718:014f:0000:0000:0000:0001
    netmask 64
    gateway _enter_ipv6_gateway_here_
    dns-nameservers 2606:4700:4700::1111 2606:4700:4700::1001 #cloudflare dns

stxsh

@Ruriko did you assign both ips to your instance from the panel?

if you did, try adding the /64 subnet to the second ip

iface venet0 inet6 static
    address 2a0a:6040:9718:14f::a/64
    up ip -6 r a default dev venet0
    up ip -6 address add 2a0a:6040:9718:14f::1/64 dev venet0

to confirm both ips:

curl -6 --interface 2a0a:6040:9718:14f::a https://ifconfig.co
curl -6 --interface 2a0a:6040:9718:14f::1 https://ifconfig.co

also: try with an ip other than ::1

Ruriko

@stxsh said:
@Ruriko did you assign both ips to your instance from the panel?

Oh it looks like my panel has no option to add ips I guess it may be a bug so I'll ask my host provider.

BTW how much RAM do I need for a vps to able to handle 100 ipv6?

stxsh

Oh it looks like my panel has no option to add ips I guess it may be a bug so I'll ask my host provider.

I’m guessing this is NATKVM since Gullo gives you an /80 and has subnet management in SolusVM. Although that looks to be an OpenVZ network config and I think NATKVM is KVM. Regardless, the IP in your config did need a /64 appended to be a valid config.

BTW how much RAM do I need for a vps to able to handle 100 ipv6?

Shouldn’t matter, but keep an eye on the free ram as you append/add a few IPs.

Also, if you are using OpenVZ, you might need a way to append those up ip -6 address add lines for each IPv6 you want, on every reboot. Set up a script or service to do that for you.

yoursunny

For OpenVZ, you must assign each and every single address from the control panel.
It isn't possible to add addresses from within the container.

vsys_host

Agree with @yoursunny
The only way for your case is to ask VPS provider's support to add additional IPs