Options for bastion, SSH config, static inventory autogeneration

* At the provisioning stage, allow users to auto-generate SSH config,
  when using a static inventory.
* Run playbooks to provsion and post-provision as a separate, when
  using a bastion. This re-applies the SSH config, which ansible can't
  do on the fly.
* Support a pre-installed bastion node, colocated with the 1st infra
  node.
* With a bastion enabled, reduce floating IP footprint to infra and
  dns nodes only, effectively isolating a cluster in a private
  network.

Signed-off-by: Bogdan Dobrelya <bdobreli@redhat.com>

6 files changed, 51 insertions, 7 deletions

diff --git a/playbooks/provisioning/openstack/README.md b/playbooks/provisioning/openstack/README.md
index 1ff586b49..6b9e5a3a9 100644
--- a/playbooks/provisioning/openstack/README.md
+++ b/playbooks/provisioning/openstack/README.md
@@ -40,7 +40,7 @@ Alternatively you can install directly from github:
       -p openshift-ansible-contrib/roles
 
 Notes:
-* This assumes we're in the directory that contains the clonned 
+* This assumes we're in the directory that contains the clonned
 openshift-ansible-contrib repo in its root path.
 * When trying to install a different version, the previous one must be removed first
 (`infra-ansible` directory from [roles](https://github.com/openshift/openshift-ansible-contrib/tree/master/roles)).
@@ -177,16 +177,30 @@ variables for the `inventory/group_vars/OSEv3.yml`, `all.yml`:
     origin_release: 1.5.1
     openshift_deployment_type: "{{ deployment_type }}"
 
-### Configure static inventory
+### Configure static inventory and access via a bastion node
 
 Example inventory variables:
 
+    openstack_use_bastion: true
+    bastion_ingress_cidr: "{{openstack_subnet_prefix}}.0/24"
     openstack_private_ssh_key: ~/.ssh/openshift
     openstack_inventory: static
     openstack_inventory_path: ../../../../inventory
+    openstack_ssh_config_path: /tmp/ssh.config.openshift.ansible.openshift.example.com
 
+The `openstack_subnet_prefix` is the openstack private network for your cluster.
+And the `bastion_ingress_cidr` defines accepted range for SSH connections to nodes
+additionally to the `ssh_ingress_cidr`` (see the security notes above).
 
-In this guide, the latter points to the current directory, where you run ansible commands
+The SSH config will be stored on the ansible control node by the
+gitven path. Ansible uses it automatically. To access the cluster nodes with
+that ssh config, use the `-F` prefix, f.e.:
+
+    ssh -F /tmp/ssh.config.openshift.ansible.openshift.example.com master-0.openshift.example.com echo OK
+
+Note, relative paths will not work for the `openstack_ssh_config_path`, but it
+works for the `openstack_private_ssh_key` and `openstack_inventory_path`. In this
+guide, the latter points to the current directory, where you run ansible commands
 from.
 
 To verify nodes connectivity, use the command:
@@ -194,7 +208,7 @@ To verify nodes connectivity, use the command:
     ansible -v -i inventory/hosts -m ping all
 
 If something is broken, double-check the inventory variables, paths and the
-generated `<openstack_inventory_path>/hosts` file.
+generated `<openstack_inventory_path>/hosts` and `openstack_ssh_config_path` files.
 
 The `inventory: dynamic` can be used instead to access cluster nodes directly via
 floating IPs. In this mode you can not use a bastion node and should specify
@@ -213,6 +227,15 @@ this is how you stat the provisioning process from your ansible control node:
 Note, here you start with an empty inventory. The static inventory will be populated
 with data so you can omit providing additional arguments for future ansible commands.
 
+If bastion enabled, the generates SSH config must be applied for ansible.
+Otherwise, it is auto included by the previous step. In order to execute it
+as a separate playbook, use the following command:
+
+    ansible-playbook openshift-ansible-contrib/playbooks/provisioning/openstack/post-provision-openstack.yml
+
+The first infra node then becomes a bastion node as well and proxies access
+for future ansible commands. The post-provision step also configures Satellite,
+if requested, and DNS server, and ensures other OpenShift requirements to be met.
 
 ### Install OpenShift
 
diff --git a/playbooks/provisioning/openstack/openstack_dns_records.yml b/playbooks/provisioning/openstack/openstack_dns_records.yml
index b5f0840c5..980221ed6 100644
--- a/playbooks/provisioning/openstack/openstack_dns_records.yml
+++ b/playbooks/provisioning/openstack/openstack_dns_records.yml
@@ -36,11 +36,13 @@
   set_fact:
     public_records: "{{ public_records | default([]) + [ { 'type': 'A', 'hostname': hostvars[item]['ansible_hostname'], 'ip': hostvars[item]['public_v4'] } ] }}"
   with_items: "{{ groups['cluster_hosts'] }}"
+  when: hostvars[item]['public_v4'] is defined
 
 - name: "Add wildcard records to the public A records"
   set_fact:
     public_records: "{{ public_records | default([]) + [ { 'type': 'A', 'hostname': '*.' + openshift_app_domain, 'ip': hostvars[item]['public_v4'] } ] }}"
   with_items: "{{ groups['infra_hosts'] }}"
+  when: hostvars[item]['public_v4'] is defined
 
 - name: "Set the public DNS server details to use the external value (if provided)"
   set_fact:
diff --git a/playbooks/provisioning/openstack/post-provision-openstack.yml b/playbooks/provisioning/openstack/post-provision-openstack.yml
index a807c4d2f..c7df74a87 100644
--- a/playbooks/provisioning/openstack/post-provision-openstack.yml
+++ b/playbooks/provisioning/openstack/post-provision-openstack.yml
@@ -4,7 +4,11 @@
   become: False
   gather_facts: False
   tasks:
-    - wait_for_connection:
+    - when: not openstack_use_bastion|default(False)|bool
+      wait_for_connection:
+    - when: openstack_use_bastion|default(False)|bool
+      delegate_to: bastion
+      wait_for_connection:
 
 - hosts: cluster_hosts
   gather_facts: True
diff --git a/playbooks/provisioning/openstack/provision-openstack.yml b/playbooks/provisioning/openstack/provision-openstack.yml
index 0cac37aaf..6ec944d56 100644
--- a/playbooks/provisioning/openstack/provision-openstack.yml
+++ b/playbooks/provisioning/openstack/provision-openstack.yml
@@ -12,13 +12,20 @@
       when: openstack_inventory|default('static') == 'static'
       inventory_path: "{{ openstack_inventory_path|default(inventory_dir) }}"
       private_ssh_key: "{{ openstack_private_ssh_key|default('~/.ssh/id_rsa') }}"
+      ssh_config_path: "{{ openstack_ssh_config_path|default('/tmp/ssh.config.openshift.ansible' + '.' + stack_name) }}"
+      ssh_user: "{{ ansible_user }}"
 
-- name: Refresh Server inventory
+- name: Refresh Server inventory or exit to apply SSH config
   hosts: localhost
   connection: local
   become: False
   gather_facts: False
   tasks:
-    - meta: refresh_inventory
+    - name: Exit to apply SSH config for a bastion
+      meta: end_play
+      when: openstack_use_bastion|default(False)|bool
+    - name: Refresh Server inventory
+      meta: refresh_inventory
 
 - include: post-provision-openstack.yml
+  when: not openstack_use_bastion|default(False)|bool
diff --git a/playbooks/provisioning/openstack/sample-inventory/group_vars/all.yml b/playbooks/provisioning/openstack/sample-inventory/group_vars/all.yml
index 9eb36ab13..6d07f9b56 100644
--- a/playbooks/provisioning/openstack/sample-inventory/group_vars/all.yml
+++ b/playbooks/provisioning/openstack/sample-inventory/group_vars/all.yml
@@ -69,5 +69,12 @@ ansible_user: openshift
 # # The path to checkpoint the static inventory from the in-memory one
 #openstack_inventory_path: ../../../../inventory
 
+# # Use bastion node to access cluster nodes (Defaults to False).
+# # Requires a static inventory.
+#openstack_use_bastion: False
+#bastion_ingress_cidr: "{{openstack_subnet_prefix}}.0/24"
+#
 # # The Nova key-pair's private SSH key to access inventory nodes
 #openstack_private_ssh_key: ~/.ssh/openshift
+# # The path for the SSH config to access all nodes
+#openstack_ssh_config_path: /tmp/ssh.config.openshift.ansible.{{ env_id }}.{{ public_dns_domain }}
diff --git a/playbooks/provisioning/openstack/stack_params.yaml b/playbooks/provisioning/openstack/stack_params.yaml
index 9c0b09b45..c3a42ab06 100644
--- a/playbooks/provisioning/openstack/stack_params.yaml
+++ b/playbooks/provisioning/openstack/stack_params.yaml
@@ -21,3 +21,4 @@ master_volume_size: "{{ docker_volume_size }}"
 app_volume_size: "{{ docker_volume_size }}"
 infra_volume_size: "{{ docker_volume_size }}"
 nodes_to_remove: "{{ openstack_nodes_to_remove | default([]) |  to_yaml }}"
+use_bastion: "{{ openstack_use_bastion|default(False) }}"