WIP: Libvirt VM creation

ansible/create_libvirt_vms.yml

@@ -4,9 +4,7 @@
     name: stackhpc.libvirt-vm
   vars:
     libvirt_vm_default_console_log_dir: "{{ console_log_directory }}"
-    libvirt_vms:
-      - state: present
-        name:   
-  run_once: true
-  # FIXME(w-miller): Schedule to different hypervisors.
-  delegate_to: "{{ groups['libvirt'][0] }}"
+    # Configure VM definitions for the Libvirt provider.
+    libvirt_vms: >
+      {{ vms | map('set_libvirt_interfaces')
+             | map('set_libvirt_volume_pool') }}

ansible/deploy.yml

@@ -6,12 +6,25 @@
 - hosts: controllers
   tasks:
     - include_tasks: schedule.yml
+
+    - name: Load allocations from file
+      include_vars:
+        file: "{{ allocations_file_path }}"
+        name: allocations
+
+- hosts: hypervisors
+  tasks:
+    - include_tasks: vm_networking.yml
       vars:
+        vm: "{{ item }}"
+      # Allocations are stored in the controller node's vars.
+      loop: >
+        {{ hostvars[groups.controllers.0].allocations.result[
+           inventory_hostname] | default([]) }}
 
 - hosts: libvirt
   tasks:
-    - name: Configure host as a Libvirt/QEMU/KVM hypervisor
-      include_role:
+    - include_role:
         name: stackhpc.libvirt-host
       vars:
         libvirt_host_pools:
@@ -24,8 +37,9 @@
             group: "{{ libvirt_pool_group }}"
         libvirt_host_require_vt: "{{ libvirt_require_vt }}"
 
-    - name: Create Libvirt VMs
-      include_tasks: create_libvirt_vms.yml
+    - include_tasks: create_libvirt_vms.yml
       vars:
-        flavour: flav0
-        name: "{{ item }}"
+        # Allocations are stored in the controller node's vars.
+        vms: >
+          {{ hostvars[groups.controllers.0].allocations.result[
+               inventory_hostname] | default([]) }}

ansible/group_vars/controllers

@@ -1,6 +1,7 @@
 ---
 # FIXME(w-miller): set this more cleverly?
 base_path: "~/tenks/"
+allocations_file_path: "{{ base_path + '/allocations.yml' }}"
 
 flavours:
   flav0:

ansible/group_vars/hypervisors

@@ -20,11 +20,19 @@ python_requirements:
 # {{ bridge_prefix + i }}, where `i` is the index of the physical network in
 # physnet_mappings (sorted alphabetically by key).
 bridge_prefix: brtenks
-# Naming scheme for veth pairs connected to the Tenks OVS bridge.
-veth_prefix: p-
-# Used for the port on the Tenks OVS bridge.
-veth_tenks_suffix: "-ovs"
-# Used for the port on the existing bridge.
-veth_source_suffix: "-phy"
+
+# Prefix for all veth links.
+veth_prefix: 'p-'
+
+# Suffix for veth links attached to a Tenks OVS bridge.
+veth_bridge_ovs_suffix: '-ovs'
+# Suffix for veth links attached to a source Linux bridge.
+veth_bridge_source_suffix: '-phy'
+
+# Suffix for veth links attached to a Tenks OVS bridge.
+veth_vm_ovs_suffix: '-ovs'
+# Suffix for veth links attached to a VM. VMs aren't physical so '-phy' doesn't
+# seem right.
+veth_vm_source_suffix: '-tap'
 
 console_log_directory: /var/log/tenks/console_logs/

ansible/host_setup.yml

@@ -33,7 +33,7 @@
   # to a containerised version of OVS.
   when: ovs_vsctl_check.rc == 127
 
-- name: Configure physical network
+- name: Configure physical networks
   include_tasks: physical_network.yml
   vars:
     network_name: "{{ item.0 }}"

ansible/physical_network.yml

@@ -43,33 +43,16 @@
 
 - name: Connect to existing Linux bridge
   when: source_type == 'linux_bridge'
-  block:
-    - name: Create veth pair
-      command: >
-        ip link add dev {{ veth_prefix + tenks_bridge + veth_tenks_suffix }}
-        type veth
-        peer name {{ veth_prefix +  tenks_bridge + veth_source_suffix }}
-      register: res
-      changed_when: res.rc == 0
-      # Return code 2 means the veth pair already exists
-      failed_when: res.rc not in [0, 2]
-      become: true
-
-    - name: Plug veth into Tenks bridge
-      openvswitch_port:
-        bridge: "{{ tenks_bridge }}"
-        port: "{{ veth_prefix + tenks_bridge + veth_tenks_suffix }}"
-
-    - name: Plug veth into source interface
-      command: >
-        brctl addif {{ source_interface }}
-        {{ veth_prefix + tenks_bridge + veth_source_suffix }}
-      register: res
-      failed_when:
-        - res.rc != 0
-        - "'already a member of a bridge' not in res.stderr"
-      changed_when: "'already a member of a bridge' not in res.stderr"
-      become: true
+  include_role:
+    name: veth-pair
+  vars:
+    veth_pair_ovs_bridge: "{{ tenks_bridge }}"
+    veth_pair_ovs_link_name: >
+      {{ veth_prefix + tenks_bridge + veth_bridge_ovs_suffix }}
+    veth_pair_source_bridge: "{{ source_interface }}"
+    veth_pair_source_link_name: >
+      {{ veth_prefix + tenks_bridge + veth_bridge_source_suffix }}
+    plug_into_source: true
 
 - name: Connect to existing Open vSwitch bridge
   when: source_type == 'ovs_bridge'

ansible/vm_networking.yml

@@ -0,0 +1,30 @@
+---
+- block:
+  - set_fact:
+      # The index of the physical network within this hypervisor's physical
+      # networks.
+      idx: >
+        {{ (physnet_mappings | dictsort | list).index(
+             (item, physnet_mappings.item)) }}
+      # Veth pairs are unique for any VM-physnet combination. However, device
+      # names cannot be longer than 15 characters, so use physical networks'
+      # indices instead.
+      veth_base_name: "{{ veth_prefix + vm.name + '-' + idx }}"
+
+  - name: Set VM veth device names
+    set_fact:
+      veths: >
+        {{ (interfaces | default([])).append(veth_base_name +
+                                             veth_vm_source_suffix) }}
+
+  - name: Set up veth pairs for the VM
+    include_role:
+      name: veth-pair
+    vars:
+      veth_pair_ovs_bridge: >
+        {{ bridge_prefix ~ idx }}
+      veth_pair_ovs_link_name: "{{ veth_base_name + veth_vm_ovs_suffix }}"
+      veth_pair_source_link_name: >
+        {{ veth_base_name + veth_vm_source_suffix }}
+
+  loop: "{{ vm.physical_networks }}"