..
   SPDX-FileCopyrightText: © 2020 Open Networking Foundation <support@opennetworking.org>
   SPDX-License-Identifier: Apache-2.0

VPN Bootstrap
=============

This section guides you through setting up a VPN connection between Aether
Central in GCP and ACE.
We will be using GitOps based Aether CI/CD system for this and what you need to do is
create a patch for the new edge in ``aether-pod-configs``, where all edge infrastructure
configuration is stored.

Here is a brief overview of each step. Note that some of the steps described here are not
directly related to setting up a VPN, but are prerequisites for adding a new edge.

**1. Add deployment jobs**
Each edge has its own Jenkins jobs that build and execute an infrastructure change plan
based on the configurations specified in aether-pod-configs.
In this step, you'll add those jobs to Aether CI/CD system for the new edge.

**2. Update global resource maps**
aether-pod-configs maintains complete list of clusters, VPN connections, and users
in separate global resource files. Before adding edge specific configurations,
it is required to update those global resource maps first.

**3. Generate Ansible and Terraform configs**
In this step, you'll add Ansible and Terraform configs necessary to install and
configure VPN software at the edge and set up VPN gateway, router, and firewall
on GCP.

**4. Submit your changes**
Finally, submit your aether-pod-configs changes to run the deployment job added
in the first step.

.. attention::

   If you are adding another ACE to an existing VPN connection, go to
   :ref:`Add ACE to an existing VPN connection <add_ace_to_vpn>`.

.. attention::

  Make sure that UDP port 500, UDP port 4500, and ESP from **gcpvpn1.infra.aetherproject.net(35.242.47.15)**
  and **gcpvpn2.infra.aetherproject.net(34.104.68.78)** are allowed in the firewall at the edge.

.. _add_deployment_jobs:

Add deployment jobs
-------------------
First, you need to add Jenkins jobs to Aether CI/CD system that build and apply infrastructure change
plans for the new edge. This can be done by creating a patch to **aether-ci-management** repository.

Download **aether-ci-management** repository.

.. code-block:: shell

   $ cd $WORKDIR
   $ git clone "ssh://[username]@gerrit.opencord.org:29418/aether-ci-management"

Add the jobs for the new cluster at the end of the ``cd-pipeline-terraform-ace-prd`` project job list.
Make sure to add both pre-merge and post-merge jobs.
Note that the cluster name specified here will be used in the rest of the deployment procedure.

.. code-block:: diff

   $ cd $WORKDIR/aether-ci-management
   $ vi jjb/repos/cd-pipeline-terraform.yaml

   # Add jobs for the new cluster
   diff jjb/repos/cd-pipeline-terraform.yamll
   --- a/jjb/repos/cd-pipeline-terraform.yaml
   +++ b/jjb/repos/cd-pipeline-terraform.yaml
   @@ -227,3 +227,9 @@
          - 'cd-pipeline-terraform-postmerge-cluster':
              cluster: 'ace-eks'
   +      - 'cd-pipeline-terraform-premerge-cluster':
   +          cluster: 'ace-test'
   +          disable-job: false
   +      - 'cd-pipeline-terraform-postmerge-cluster':
   +          cluster: 'ace-test'
   +          disable-job: false

Submit your change and wait for the jobs you just added available in Aether Jenkins.

.. code-block:: shell

   $ git status
   Changes not staged for commit:

     modified:   jjb/repos/cd-pipeline-terraform.yaml

   $ git add .
   $ git commit -m "Add test ACE deployment job"
   $ git review


Get access to encrypted files in aether-pod-configs repository
--------------------------------------------------------------

`git-crypt <https://github.com/AGWA/git-crypt>`_ is used to securely store encrypted files
in the aether-pod-configs repository. Before proceeding, (1) install git-crypt and `gpg <https://gnupg.org/>`_,
(2) create a GPG keypair, and (3) ask a member of the Aether OPs team to add your public key
to the aether-pod-configs keyring.  To create the keypair follow these steps:

.. code-block:: shell

   $ gpg --full-generate-key
   $ gpg --output <key-name>.gpg --armor --export <your-email-address>

.. _update_global_resource:

Update global resource maps
---------------------------

Download aether-pod-configs repository.

.. code-block:: shell

   $ cd $WORKDIR
   $ git clone "ssh://[username]@gerrit.opencord.org:29418/aether-pod-configs"
   $ git-crypt unlock

Add the new cluster information at the end of the following global resource maps.

* ``cluster_map.tfvars``
* ``vpn_map.tfvars``

.. code-block:: diff

   $ cd $WORKDIR/aether-pod-configs/production
   $ vi cluster_map.tfvars

   # Add the new K8S cluster information at the end of the cluster group it belongs to
   $ git diff cluster_map.tfvars
   --- a/production/cluster_map.tfvars
   +++ b/production/cluster_map.tfvars
   @@ cluster_map = {
         kube_dns_cluster_ip     = "10.53.128.10"
         cluster_domain          = "prd.menlo.aetherproject.net"
         calico_ip_detect_method = "can-reach=www.google.com"
   +    },
   +    ace-test = {
   +      cluster_name            = "ace-test"
   +      management_subnets      = ["10.32.4.0/24"]
   +      k8s_version             = "v1.18.8-rancher1-1"
   +      k8s_pod_range           = "10.33.0.0/17"
   +      k8s_cluster_ip_range    = "10.33.128.0/17"
   +      kube_dns_cluster_ip     = "10.33.128.10"
   +      cluster_domain          = "prd.test.aetherproject.net"
   +      calico_ip_detect_method = "can-reach=www.google.com"
         }
      }
   }

.. code-block:: diff

   $ cd $WORKDIR/aether-pod-configs/production
   $ vi vpn_map.tfvars

   # Add VPN and tunnel information at the end of the map
   $ git diff vpn_map.tfvars
   --- a/production/vpn_map.tfvars
   +++ b/production/vpn_map.tfvars
   @@ vpn_map = {
      bgp_peer_ip_address_1    = "169.254.0.6"
      bgp_peer_ip_range_2      = "169.254.1.5/30"
      bgp_peer_ip_address_2    = "169.254.1.6"
   +  },
   +  ace-test = {
   +    peer_name                = "production-ace-test"
   +    peer_vpn_gateway_address = "66.201.42.222"
   +    tunnel_shared_secret     = "UMAoZA7blv6gd3IaArDqgK2s0sDB8mlI"
   +    bgp_peer_asn             = "65003"
   +    bgp_peer_ip_range_1      = "169.254.0.9/30"
   +    bgp_peer_ip_address_1    = "169.254.0.10"
   +    bgp_peer_ip_range_2      = "169.254.1.9/30"
   +    bgp_peer_ip_address_2    = "169.254.1.10"
      }
   }

.. note::
   Use `this site <https://cloud.google.com/network-connectivity/docs/vpn/how-to/generating-pre-shared-key/>`_
   to generate a strong tunnel shared secret.

.. note::
   Unless you have a specific requirement, set ASN to the next available value in the map.
   For BGP peer IP range and address, use the next available /30 subnet in the map.


Generate Ansible and Terraform configurations
---------------------------------------------

In this step, we will create a directory under ``production`` with the same name
as the cluster, and add Ansible and Terraform configurations needed
to configure a VPN in ACE and GCP using a tool.

.. code-block:: shell

   $ cd $WORKDIR/aether-pod-configs/tools
   $ cp ace_config.yaml.example ace_config.yaml

   # Set all values in ace_config.yaml
   $ vi ace_config.yaml

   $ make vpn
   Created ../production/ace-test
   Created ../production/ace-test/provider.tf
   Created ../production/ace-test/cluster.tf
   Created ../production/ace-test/gcp_ha_vpn.tf
   Created ../production/ace-test/gcp_fw.tf
   Created ../production/ace-test/backend.tf
   Created ../production/ace-test/cluster_val.tfvars
   Created ../production/ace-test/ansible
   Created ../production/ace-test/ansible/hosts.ini
   Created ../production/ace-test/ansible/extra_vars.yml


Submit your change
------------------

.. code-block:: shell

   $ cd $WORKDIR/aether-pod-configs/production
   $ git status
   On branch tools
   Changes not staged for commit:

      modified:   cluster_map.tfvars
      modified:   vpn_map.tfvars

   Untracked files:
   (use "git add <file>..." to include in what will be committed)

      ace-test/

   $ git add .
   $ git commit -m "Add test ACE"
   $ git review

Wait for a while until the post-merge job finishes after the change is merged.

Verify VPN connection
---------------------

You can verify the VPN connections by checking
the routing table from the management server and trying to ping to one of the
central cluster VMs.

Be sure there are two tunnel interfaces, ``gcp_tunnel1`` and ``gcp_tunnel2``,
and three additional routing entries via one of the tunnel interfaces.

.. code-block:: shell

   # Verify routings
   $ netstat -rn
   Kernel IP routing table
   Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
   0.0.0.0         66.201.42.209   0.0.0.0         UG        0 0          0 eno1
   10.32.4.0       0.0.0.0         255.255.255.128 U         0 0          0 eno2
   10.32.4.128     0.0.0.0         255.255.255.128 U         0 0          0 mgmt800
   10.45.128.0     169.254.0.9     255.255.128.0   UG        0 0          0 gcp_tunnel1
   10.52.128.0     169.254.0.9     255.255.128.0   UG        0 0          0 gcp_tunnel1
   10.33.128.0     10.32.4.138     255.255.128.0   UG        0 0          0 mgmt800
   10.168.0.0      169.254.0.9     255.255.240.0   UG        0 0          0 gcp_tunnel1
   66.201.42.208   0.0.0.0         255.255.252.0   U         0 0          0 eno1
   169.254.0.8     0.0.0.0         255.255.255.252 U         0 0          0 gcp_tunnel1
   169.254.1.8     0.0.0.0         255.255.255.252 U         0 0          0 gcp_tunnel2

   # Verify ACC VM access
   $ ping 10.168.0.6

   # Verify ACC K8S Service access
   $ nslookup kube-dns.kube-system.svc.prd.acc.gcp.aetherproject.net 10.52.128.10

You can also login to GCP console and check if the edge subnets exist in
**VPC Network > Routes > Dynamic**.


Post VPN setup
--------------

Once you verify the VPN connections, update ``ansible`` directory name to
``_ansible`` to prevent the ansible playbook from being rerun.

.. code-block:: shell

   $ cd $WORKDIR/aether-pod-configs/production/$ACE_NAME
   $ mv ansible _ansible
   $ git add .
   $ git commit -m "Ansible done for test ACE"
   $ git review

.. _add_ace_to_vpn:

Add another ACE to an existing VPN connection
"""""""""""""""""""""""""""""""""""""""""""""

VPN connections can be shared when there are multiple ACE clusters in a site.
In order to add another cluster to an existing VPN connection, you'll have to SSH into the
management node and manually update BIRD configuration.

.. note::

   This step needs improvements in the future.

.. code-block:: shell

   $ sudo vi /etc/bird/bird.conf
   protocol static {
      # Routings for the existing cluster
      ...
      route 10.33.128.0/17 via 10.32.4.138;

      # Add routings for the new ACE's K8S cluster IP range via cluster nodes
      # TODO: Configure iBGP peering with Calico nodes and dynamically learn these routings
      route <NEW-ACE-CLUSTER-IP> via <SERVER1>
      route <NEW-ACE-CLUSTER-IP> via <SERVER2>
      route <NEW-ACE-CLUSTER-IP> via <SERVER3>
   }

   filter gcp_tunnel_out {
      # Add the new ACE's K8S cluster IP range and the management subnet if required to the list
      if (net ~ [ 10.32.4.0/24, 10.33.128.0/17, <NEW-ACE-CLUSTER-MGMT-SUBNET>, <NEW-ACE-CLUSTER-IP-RANGE> ]) then accept;
      else reject;
   }
   # Save and exit

   $ sudo birdc configure

   # Confirm the static routes are added
   $ sudo birdc show route