Open Stack

Hi All

W dniu 25.11.2015 o 14:00, Aleksandra Fedorova pisze:
> ...
> Thus the test layout as i see it should be the following:
>
> - one "manager vm" which will be responsible for the main test flow.
> On this vm we will:
>      - build fuel-library package,
>      - generate a repository,
>      - get fuel-qa code,
>      - run the actual test using based on job parameters,
>      - collect test result and artifacts.
> - one vm with installed Fuel,
> - several bootstrapped nodes according to the test configuration -
> here probably we can switch from using nodes which are bootstrapped
> with Fuel to nodes which are just the most generic ones.
>
> As i got it from reading grenade job log [1], having manager vm is
> actually expected: there is a "main" node and list of subnodes which
> you can talk to from there. So this setup is not impossible, but
> requires support for requesting different types of nodes from
> nodepool. And we probably need to patch the Zuul_v3 spec in [2] to add
> this case to the format of request-accept calls?
>
> The other question here would be the network configuration: to
> function properly Fuel needs 5 (or 6?) different networks and we will
> need a way to configure them before we run the actual deployment. What
> are the options for configuring network on top of nodes provided by
> nodepool?
>
>

Some time ago i worked on similar solution, how to execute Fuel inside 
other openstack instances. During my tests i have found problem with 
network and passing vlans between openstack instances. This problem 
could also appear when we want to use nodepool as a source of virtual 
machines for deployment tests. I will try to show where my problem exist.

As a underlying Openstack infrastructure was used Fuel 6.0 executed on 
HW nodes:
- one controler node
- 5 compute nodes
- Neutron with GRE segmentation

To reduce network issues all instances was executed on one compute node.

Test assumes that we execute fuel master and slaves as a Openstack 
instances inside one dedicated tenant. Every test requires to create a 
few networks and instances, it was easier to manage networks and 
instances as a tenant group. At the end of the test we can just delete 
all tenant objects.

Standard fuel installation requires to create few networks, i created:
- admin
- public
- mgmt
- storage

In standard Fuel installations networks could be attached directly to 
interface or created as a VLAN on network interface. In this case i 
wanted to reduce problems with additional tagging/fragmentation and each 
of network was created as a separate neutron network with dedicated 
interface inside instance.
This requires to create Neutron infrastructure with:
- router connected to external network
- 4 neutron networks
- public and admin network connected to router

Each of instance is connected to network by dedicated interface, it 
looks like this:

             +---------+
             | Neutron |   +~~~~~~~~+
      +------| router  |---|Internet|
      |      +---------+   +~~~~~~~~+
      |           |
+---------+ +---------+ +---------+ +---------+
| Neutron | | Neutron | | Neutron | | Neutron |
| network | | network | | network | | network |
|  admin  | | public  | | mgmt    | | storage |
+---------+ +---------+ +---------+ +---------+
    |     |           |       |          |
    |     +--------+  |       |          |
    |              |  |       |          |
+-----------+    +------------------------+
|Fuel Master|    |    Fuel slave X        |
+-----------+    +------------------------+

In standard Openstack installation it is not possible to start DHCP 
server on instance, it is blocked by firewall. To solve this problem i 
changed neutron agent code to allow DHCP traffic.

Shortcut from procedure used to install fuel inside openstack:
- upload ISO Fuel 6.1 to glance
- upload ISO iPXE to glance
- create instance for fuel master server and install it
- create 2 instances for fuel slave nodes and boot them from iPXE

After those steps i got fuel installation with 2 nodes ready for 
deployment, like this:

+------------------------------------------------------+
| Hardware node                                        |
|                 +------------------------+           |
|                 |    Fuel slave 1        |           |
|                 |   (KVM Instance)       |           |
|                 +------------------------+           |
|                   |  |       |          |            |
|          +--------+  |       |          |            |
|          |           |       |          |            |
| +---------+ +---------+ +---------+ +---------+      |
| | Neutron | | Neutron | | Neutron | | Neutron |      |
| | network | | network | | network | | network |      |
| |  admin  | | public  | | mgmt    | | storage |      |
| |  (OVS)  | |  (OVS)  | |  (OVS)  | |  (OVS)  |      |
| +---------+ +---------+ +---------+ +---------+      |
|    |     |           |       |          |            |
|    |     +--------+  |       |          |            |
|    |              |  |       |          |            |
| +-----------+    +------------------------+          |
| |Fuel Master|    |    Fuel slave 2        |          |
| |   (KVM)   |    |   (KVM Instance)       |          |
| +-----------+    +------------------------+          |
|                                                      |
+------------------------------------------------------+

With this configuration it was possible to deploy new Openstack, but 
some type of configurations not work correctly. Problem appears when i 
deployed Openstack with VLAN separation, OSTF tests not passes.

+------------------------------------------------------+
| Hardware node                                        |
|   +---------------------------------------+          |
|   |    Fuel slave 1  +------------------+ |          |
|   |   (KVM Instance) |Openstack Instance| |          |
|   |                  |       TEST1      | |          |
|   |                  |       (KVM)      | |          |
|   |                  +------------------+ |          |
|   |                            |          |          |
|   |                      +----------+     |          |
|   |                      |    OVS   |     |          |
|   |                      |   (VLAN) |     |          |
|   |                      +----------+     |          |
|   |                            |tag:1000  |          |
|   +---------------------------ETH---------+          |
|                                |                     |
|                          +----------+                |
|                          |    OVS   |                |
|                          |   (GRE)  |                |
|                          +----------+                |
|                                |                     |
|   +---------------------------ETH---------+          |
|   |   Fuel slave 2             |tag:1000  |          |
|   |  (KVM Instance)      +----------+     |          |
|   |                      |    OVS   |     |          |
|   |                      |   (VLAN) |     |          |
|   |                      +----------+     |          |
|   |                            |          |          |
|   |                  +------------------+ |          |
|   |                  |Openstack Instance| |          |
|   |                  |       TEST2      | |          |
|   |                  |       (KVM)      | |          |
|   |                  +------------------+ |          |
|   +---------------------------------------+          |
|                                                      |
+------------------------------------------------------+

Problem exists when we want to send packets between instances TEST1 and 
TEST2:
- packet is sent from TEST1
- OVS inside Fuel slave 1 needs to send this packet to other compute 
node inside correct tenant network, it will add VLAN tag and then will 
send it to the network interface
- OVS on hardware node will get tagged frame on OVS interface which is 
not configured for tagging and OVS will drop it

To start using nodepool instances in deployment tests we need to have 
sure that openstack used by nodepool allow to:
- send responses from DHCP server installed on fuel master to slave 
instances, packets must pass by compute node firewall, in standard 
configuration responses from DHCP server are possible only from network node
- we have solution which allow to pass tagged vlans between Openstack 
Instances, without this we cannot execute all kind of tests and scenarios

Is it possible in actual Openstack infrastructure used by nodepool?
Or maybe we could solve it in other way?

--
Artur Kaszuba