configure ipv6 virtual machine esxi

Configuring IPv6 on virtual machines with ESXi

Published on 24 February 2022

compute
dedibox
esxi
vm
virtual-machine
ubuntu

This tutorial explains how to configure IPv6 on virtual machines on ESXi hypervisors.

Security & Identity (IAM):

You may need certain IAM permissions to carry out some actions described on this page. This means:

you are the Owner of the Scaleway Organization in which the actions will be carried out, or
you are an IAM user of the Organization, with a policy granting you the necessary permission sets

Requirements:

You have an account and are logged into the Scaleway console
You have configured your SSH Key
You have a Dedibox running ESXi 6.5 or later
You have enabled SLAAC for your Dedibox
You have requested an IPv6 prefix
You have installed a virtual machine running Ubuntu 20.04 or later and configured a failover IPv4 on it

Log into your virtual machine using SSH.

Run the command ip a to display your current network configuration. The command returns an output as follows:

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
   valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
   valid_lft forever preferred_lft forever
2: ens160: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
link/ether 00:50:56:01:fa:b9 brd ff:ff:ff:ff:ff:ff
altname enp3s0
inet your.fail.over.ip/32 scope global ens160
   valid_lft forever preferred_lft forever
inet6 fe80::250:56ff:fe01:fab9/64 scope link
   valid_lft forever preferred_lft forever

Take note of the following information from the output above:

The name of the network interface (here ens160)
The local IPv6 of your VM (here fe80::250:56ff:fe01:fab9/64)

Open the file /etc/dhcp/dhclient6.conf in a text editor and edit it as shown below. Then save the file and quit the text editor.
```
interface "ens160" {
    send dhcp6.client-id DUID;
}
```
Important:
Edit the name of the Internet interface to the one of your VM and replace DUID with the DUID of your prefix.

Open the file /etc/systemd/system/dhclient.service in a text editor and edit it as shown below. Then save and exit the editor.

[Unit]
Description=dhclient for sending DUID IPv6
After=network-online.target
Wants=network-online.target
[Service]
Restart=always
RestartSec=10
Type=forking
ExecStart=/sbin/dhclient -cf /etc/dhcp/dhclient6.conf -6 -P -v eno1
ExecStop=/sbin/dhclient -x -pf /var/run/dhclient6.pid
[Install]
WantedBy=network.target

Enable the service to start automatically after each reboot of the machine. Then start the service manually for the first time.
```
systemctl enable dhclient.service
systemctl start dhclient.service
```

Verify that the service is running with the following command:

systemctl status dhclient.service

The command above returns an output as follows:

    ● dhclient.service - dhclient for sending DUID IPv6
    Loaded: loaded (/etc/systemd/system/dhclient.service; enabled; vendor pres>
    Active: active (running) since Thu 2022-02-24 12:18:03 UTC; 27min ago
  Main PID: 5342 (dhclient)
    Tasks: 4 (limit: 4627)
    Memory: 1.6M
    CPU: 23ms
    CGroup: /system.slice/dhclient.service
            └─5342 /sbin/dhclient -cf /etc/dhcp/dhclient6.conf -6 -P -v ens160

Edit your Netplan configuration file (probably located at /etc/netplan/01-netcfg.yaml) and edit it as follows:

network:
version: 2
renderer: networkd
ethernets:
    ens160:
    dhcp4: false
    dhcp6: false
    addresses:
    - FAILOVER_IP/32
    - IP_FROM_YOUR_PREFIX/SUBNET
    gateway4: 62.210.0.1
    gateway6: LOCAL_IPv6
    nameservers:
        addresses: [62.210.16.6, 62.210.16.7]
    routes:
    - to: 0.0.0.0/0
        via: 62.210.0.1
        on-link: true
    - to: "::/0"
        via: "LOCAL_IPv6"
        on-link: true

Apply the new network configuration with the following command:
```
netplan apply 
```
You now have configured the IP address, but the IPv6 connectivity is not working yet.

Find the gateway for your prefix by running the following command:

ip -6 route

The command returns an output as follows:

::1 dev lo proto kernel metric 256 pref medium
YOUR_IPv6_PREFIX/SUBNETMASK dev ens160 proto kernel metric 256 pref medium
fe80::/64 dev ens160 proto kernel metric 256 pref medium
default via fe80::7a0c:f0ff:fedf:254d dev ens160 proto static metric 1024 onlink pref medium

Take a note of the default gateway (here fe80::7a0c:f0ff:fedf:254d).

Edit your Netplan configuration file again and modify it as follows:
```
gateway6: DEFAULT_GATEWAY 
- to: "::/0"
    via: "DEFAULT_GATEWAY"
    on-link: true
```
Note:
Remember to replace DEFAULT_GATEWAY with the default gateway found in the previous step.
Reload your network configuration for the last time:
```
netplan apply 
```

You have now IPv6 connectivity for your virtual machine. You can test it by running a ping6: ping ipv6.google.com.