|KemoNine 53efc122e3||2 months ago|
|defaults||2 months ago|
|handlers||2 months ago|
|meta||5 months ago|
|tasks||2 months ago|
|templates||2 months ago|
|CHANGELOG.md||4 months ago|
|README.md||2 months ago|
This Ansible role is used in my blog series Kubernetes the not so hard way with Ansible but can be used standalone of course. I use WireGuard and this Ansible role to setup a fully meshed VPN between all nodes of my little Kubernetes cluster. This VPN also includes two clients so that I can communicate securly with the Kubernetes API server. Also my Postfix mailserver running as K8s DaemonSet forwards mails to my internal Postfix through WireGuard VPN.
I used PeerVPN before but that wasn't updated for a while. As I moved my cloud hosts from Scaleway to Hetzner cloud it was a good time to switch the VPN solution ;-) In general PeerVPN still works perfectly fine esp. if you need a easy to setup fully meshed network (where every node is able to talk to all other nodes and even if node
A should be able to talk to Node
C via node
B ;-) ). But PeerVPN needs also lot of CPU resources and throuhput could be better. That's solved with WireGuard.
In general WireGuard is a network tunnel (VPN) for IPv4 and IPv6 that uses UDP. If you need more information about WireGuard you can find a good introduction here: Installing WireGuard, the Modern VPN.
This role is tested with Ubuntu 18.04 (Bionic Beaver), Ubuntu 20 (Focal Fossa) and Archlinux. Ubuntu 16.04 (Xenial Xerus), Debian 9 (Stretch), Debian 10 (Buster), Fedora 31 (or later) and CentOS 7 might also work or other distributions but haven't tested it (code for this operating systems was submitted by other contributors). If someone tested it let me please know if it works or send a pull request to make it work ;-)
I tag every release and try to stay with semantic versioning. If you want to use the role I recommend to checkout the latest tag. The master branch is basically development while the tags mark stable releases. But in general I try to keep master in good shape too.
By default port
51820 (protocol UDP) should be accessable from the outside. But you can adjust the port by changing the variable
wireguard_port. Also IP forwarding needs to be enabled e.g. via
echo 1 > /proc/sys/net/ipv4/ip_forward . I decided not to implement this task in this Ansible role. IMHO that should be handled elsewhere. You can use my ansible-role-harden-linux e.g. Besides changing sysctl entries (which you need to enable IP forwarding) it also manages firewall settings among other things. Nevertheless the
PostDown hooks may be a good place to do some network related stuff before a WireGuard interface comes up or goes down.
These variables can be changed in
# Directory to store WireGuard configuration on the remote hosts wireguard_remote_directory: "/etc/wireguard" # The default port WireGuard will listen if not specified otherwise. wireguard_port: "51820" # The default interface name that wireguard should use if not specified otherwise. wireguard_interface: "wg0"
The following variable is mandatory and needs to be configured for every host in
Of course all IP's should be in the same subnet like
/24 we see in the example above. If
wireguard_allowed_ips is not set then the default value is the value from
wireguard_address without the CIDR but instead with
/32 which is basically a host route (have a look
templates/wg.conf.j2). Let's see this example and let's assume you don't set
[Interface] Address = 10.8.0.2/24 PrivateKey = .... ListenPort = 51820 [Peer] PrivateKey = .... AllowedIPs = 10.8.0.101/32 Endpoint = controller01.p.domain.tld:51820
This is part of the WireGuard config from my workstation. It has the VPN IP
10.8.0.2 and we've a
/24 subnet in which all my WireGuard hosts are located. Also you can see we've a peer here that has the endpoint
wireguard_allowed_ips is not explicitly set the Ansible template will add an
AllowedIPs entry with the IP of that host plus
/32. In WireGuard this basically specifies the routing. The config above says: On my workstation with the IP
10.8.0.2 I want send all traffic to
10.8.0.101/32 to the endpoint
controller01.p.domain.tld:51820. Now let's assume we set
wireguard_allowed_ips: "0.0.0.0/0". Then the resulting config looks like this.
[Interface] Address = 10.8.0.2/24 PrivateKey = .... ListenPort = 51820 [Peer] PrivateKey = .... AllowedIPs = 0.0.0.0/0 Endpoint = controller01.p.domain.tld:51820
Now this is basically the same as above BUT now the config says: I want to route EVERY traffic originating from my workstation to the endpoint
controller01.p.domain.tld:51820. If that endpoint can handle the traffic is of course another thing and it's up to you how you configure the endpoint routing ;-)
You can specify further optional settings (they don't have a default and won't be set if not specified besides
wireguard_allowed_ips as already mentioned) also per host in
host_vars/ (or in your Ansible hosts file if you like). The values for the following variables are just examples and no defaults (for more information and examples see wg-quick.8):
wireguard_allowed_ips: "" wireguard_endpoint: "host1.domain.tld" wireguard_persistent_keepalive: "30" wireguard_dns: "220.127.116.11" wireguard_fwmark: "1234" wireguard_mtu: "1492" wireguard_table: "5000" wireguard_preup: - ... wireguard_predown: - ... wireguard_postup: - ... wireguard_postdown: - ... wireguard_save_config: "true"
wireguard_(preup|predown|postup|postdown) are specified as lists. Here are two examples:
wireguard_postup: - iptables -t nat -A POSTROUTING -o ens12 -j MASQUERADE - iptables -A FORWARD -i %i -j ACCEPT - iptables -A FORWARD -o %i -j ACCEPT
wireguard_preup: - echo 1 > /proc/sys/net/ipv4/ip_forward - ufw allow 51820/udp
The commands are executed in order as described in wg-quick.8.
wireguard_address is required as already mentioned. It's the IP of the interface name defined with
wireguard_interface variable (
wg0 by default). Every host needs a unique VPN IP of course. If you don't set
wireguard_endpoint the playbook will use the hostname defined in the
vpn hosts group (the Ansible inventory hostname). If you set
"" (empty string) that peer won't have a endpoint. That means that this host can only access hosts that have a
wireguard_endpoint. That's useful for clients that don't expose any services to the VPN and only want to access services on other hosts. So if you only define one host with
wireguard_endpoint set and all other hosts have
wireguard_endpoint set to
"" (empty string) that basically means you've only clients besides one which in that case is the WireGuard server. The third possibility is to set
wireguard_endpoint to some hostname. E.g. if you have different hostnames for the private and public DNS of that host and need different DNS entries for that case setting
wireguard_endpoint becomes handy. Take for example the IP above:
wireguard_address: "10.8.0.101". That's a private IP and I've created a DNS entry for that private IP like
i for internal in that case). For the public IP I've created a DNS entry like
p for public). The
wireguard_endpoint needs to be a interface that the other members in the
vpn group can connect to. So in that case I would set
host01.p.domain.tld because WireGuard normally needs to be able to connect to the public IP of the other host(s).
Here is a litte example for what I use the playbook: I use WireGuard to setup a fully meshed VPN (every host can directly connect to every other host) and run my Kubernetes (K8s) cluster at Hetzner Cloud (but you should be able to use any hoster you want). So the important components like the K8s controller and worker nodes (which includes the pods) only communicate via encrypted WireGuard VPN. Also (as already) mentioned I've two clients. Both have
kubectl installed and are able to talk to the internal Kubernetes API server by using WireGuard VPN. One of the two clients also exposes a WireGuard endpoint because the Postfix mailserver in the cloud and my internal Postfix needs to be able to talk to each other. I guess that's maybe a not so common use case for WireGuard :D But it shows what's possible. So let me explain the setup which might help you to use this Ansible role.
First, here is a part of my Ansible
[vpn] controller0[1:3].i.domain.tld worker0[1:2].i.domain.tld server.at.home.i.domain.tld workstation.i.domain.tld [k8s_controller] controller0[1:3].i.domain.tld [k8s_worker] worker0[1:2].i.domain.tld
As you can see I've three gropus here:
vpn (all hosts on that will get WireGuard installed),
k8s_controller (the Kubernetes controller nodes) and
k8s_worker (the Kubernetes worker nodes). The
i in the domainname is for
internal. All the
i.domain.tld DNS entries have a
A record that points to the WireGuard IP that we define shortly for every host e.g.:
controller01.i.domain.tld. IN A 10.8.0.101. The reason for that is that all Kubernetes components only binds and listen on the WireGuard interface in my setup. And since I need this internal IPs for all my Kubernetes components I specify the internal DNS entries in my Ansible
hosts file. That way I can use the Ansible inventory hostnames and variables very easy in the playbooks and templates.
For the Kubernetes controller nodes I've defined the following host variables:
Ansible host file:
--- wireguard_address: "10.8.0.101/24" wireguard_endpoint: "controller01.p.domain.tld" ansible_host: "controller01.p.domain.tld" ansible_python_interpreter: /usr/bin/python3
Ansible host file:
--- wireguard_address: "10.8.0.102/24" wireguard_endpoint: "controller02.p.domain.tld" ansible_host: "controller02.p.domain.tld" ansible_python_interpreter: /usr/bin/python3
Ansible host file:
--- wireguard_address: "10.8.0.103/24" wireguard_endpoint: "controller03.p.domain.tld" ansible_host: "controller03.p.domain.tld" ansible_python_interpreter: /usr/bin/python3
ansible_python_interpreter here for every node as the controller nodes use Ubuntu 18.04 which has Python 3 installed by default.
ansible_host is set to the public DNS of that host. Ansible will use this hostname to connect to the host via SSH. I use the same value also for
wireguard_endpoint because of the same reason. The WireGuard peers needs to connect to the other peers via a public IP (well at least via a IP that the WireGuard hosts can connect to - that could be of course also a internal IP if it works for you). The
wireguard_address needs to be unique of course for every host.
For the Kubernetes worker I've defined the following variables:
Ansible host file:
--- wireguard_address: "10.8.0.111/24" wireguard_endpoint: "worker01.p.domain.tld" wireguard_persistent_keepalive: "30" ansible_host: "worker01.p.domain.tld" ansible_python_interpreter: /usr/bin/python3
Ansible host file:
--- wireguard_address: "10.8.0.112/24" wireguard_endpoint: "worker02.p.domain.tld" wireguard_persistent_keepalive: "30" ansible_host: "worker02.p.domain.tld" ansible_python_interpreter: /usr/bin/python3
As you can see the variables are basically the same as the controller nodes have with one exception:
wireguard_persistent_keepalive: "30". My worker nodes (at Hetzner Cloud) and my internal server (my server at home) are connected because I've running Postfix at my cloud nodes and the external Postfix server forwards the received mails to my internal server (and vice versa). I needed the keepalive setting because from time to time the cloud instances and the internal server lost connection and this setting solved the problem. The reason for this is of course because my internal server is behind NAT and the firewall/router must keep the NAT/firewall mapping valid (NAT and Firewall Traversal Persistence).
For my internal server at home (connected via DSL router to the internet) we've this configuration:
--- wireguard_address: "10.8.0.1/24" wireguard_endpoint: "server.at.home.p.domain.tld" wireguard_persistent_keepalive: "30" ansible_host: 192.168.2.254 ansible_port: 22
By default the SSH daemon is listening on a different port than 22 on all of my public nodes but internally I use
22 and that's the reason to set
ansible_port: 22 here. Also
ansible_host is of course a internal IP for that host. The
wireguard_endpoint value is a dynamic DNS entry. Since my IP at home isn't static I need to run a script every minute at my home server that checks if the IP has changed and if so adjusts my DNS record. I use OVH's DynHost feature to accomplish this but you can use and DynDNS provider you want of course. Also I forward incoming traffic on port
51820/UDP to my internal server to allow incoming WireGuard traffic. The
wireguard_address needs to be of course part of our WireGuard subnet.
And finally for my workstation (on which I run all
wireguard_address: "10.8.0.2/24" wireguard_endpoint: "" ansible_connection: local ansible_become: false
As you can see
wireguard_endpoint: "" is a empty string here. That means the Ansible role won't set an endpoint for my workstation. Since there is no need for the other hosts to connect to my workstation it doesn't makes sense to have a endpoint defined. So in this case I can access all hosts defined in the Ansible group
vpn from my workstation but not the other way round. So the resulting WireGuard config for my workstation looks like this:
[Interface] Address = 10.8.0.2/24 PrivateKey = .... ListenPort = 51820 [Peer] PrivateKey = .... AllowedIPs = 10.8.0.101/32 Endpoint = controller01.p.domain.tld:51820 [Peer] PrivateKey = .... AllowedIPs = 10.8.0.102/32 Endpoint = controller02.p.domain.tld:51820 [Peer] PrivateKey = .... AllowedIPs = 10.8.0.103/32 Endpoint = controller03.p.domain.tld:51820 [Peer] PrivateKey = .... AllowedIPs = 10.8.0.111/32 PersistentKeepalive = 30 Endpoint = worker01.p.domain.tld:51820 [Peer] PrivateKey = .... AllowedIPs = 10.8.0.112/32 PersistentKeepalive = 30 Endpoint = worker02.p.domain.tld:51820 [Peer] PrivateKey = .... AllowedIPs = 10.8.0.1/32 PersistentKeepalive = 30 Endpoint = server.at.home.p.domain.tld:51820
The other WireGuard config files (
wg0.conf by default) looks similar but of course
[Interface] includes the config of that specific host and the
[Peer] entries lists the config of the other hosts.
- hosts: vpn roles: - wireguard
This is a complex example using yaml inventory format:
vpn1: hosts: multi: wireguard_address: 10.9.0.1/32 wireguard_allowed_ips: "10.9.0.1/32, 192.168.2.0/24" wireguard_endpoint: multi.exemple.com nated: wireguard_address: 10.9.0.2/32 wireguard_allowed_ips: "10.9.0.2/32, 192.168.3.0/24" wireguard_persistent_keepalive: 15 wireguard_endpoint: nated.exemple.com wireguard_postup: - iptables -t nat -A POSTROUTING -o ens12 -j MASQUERADE - iptables -A FORWARD -i %i -j ACCEPT - iptables -A FORWARD -o %i -j ACCEPT wireguard_postdown: - iptables -t nat -D POSTROUTING -o ens12 -j MASQUERADE - iptables -D FORWARD -i %i -j ACCEPT - iptables -D FORWARD -o %i -j ACCEPT vpn2: hosts: # Use a different name, and define ansible_host, to avoid mixing of vars without # needing to prefix vars with interface name. multi-wg1: ansible_host: multi wireguard_interface: wg1 # when using several interface on one host, we must use different ports wireguard_port: 51821 wireguard_address: 10.9.1.1/32 wireguard_endpoint: multi.exemple.com another: wireguard_address: 10.9.1.2/32 wireguard_endpoint: another.exemple.com
- hosts: vpn1 roles: - wireguard
- hosts: vpn2 roles: - wireguard
GNU GENERAL PUBLIC LICENSE Version 3