LIBVIRT Setup instructions
==========================

`libvirt` is an `openshift-ansible` provider that uses `libvirt` to create local Fedora VMs that are provisioned exactly the same way that cloud VMs would be provisioned.

This makes `libvirt` useful to develop, test and debug Openshift and openshift-ansible locally on the developer’s workstation before going to the cloud.

Install dependencies
--------------------

1. Install [dnsmasq](http://www.thekelleys.org.uk/dnsmasq/doc.html)
2. Install [ebtables](http://ebtables.netfilter.org/)
3. Install [qemu](http://wiki.qemu.org/Main_Page)
4. Install [libvirt](http://libvirt.org/)
5. Enable and start the libvirt daemon, e.g:
   * ``systemctl enable libvirtd``
   * ``systemctl start libvirtd``
6. [Grant libvirt access to your user¹](https://libvirt.org/aclpolkit.html)
7. Check that your `$HOME` is accessible to the qemu user²

#### ¹ Depending on your distribution, libvirt access may be denied by default or may require a password at each access.

You can test it with the following command:
```
virsh -c qemu:///system pool-list
```

If you have access error messages, please read https://libvirt.org/acl.html and https://libvirt.org/aclpolkit.html .

In short, if your libvirt has been compiled with Polkit support (ex: Arch, Fedora 21), you can create `/etc/polkit-1/rules.d/50-org.libvirt.unix.manage.rules` as follows to grant full access to libvirt to `$USER`

```
sudo /bin/sh -c "cat - > /etc/polkit-1/rules.d/50-org.libvirt.unix.manage.rules" << EOF
polkit.addRule(function(action, subject) {
        if (action.id == "org.libvirt.unix.manage" &&
            subject.user == "$USER") {
                return polkit.Result.YES;
                polkit.log("action=" + action);
                polkit.log("subject=" + subject);
        }
});
EOF
```

If your libvirt has not been compiled with Polkit (ex: Ubuntu 14.04.1 LTS), check the permissions on the libvirt unix socket:

```
ls -l /var/run/libvirt/libvirt-sock
srwxrwx--- 1 root libvirtd 0 févr. 12 16:03 /var/run/libvirt/libvirt-sock

usermod -a -G libvirtd $USER
# $USER needs to logout/login to have the new group be taken into account
```

(Replace `$USER` with your login name)

#### ² Qemu will run with a specific user. It must have access to the VMs drives

All the disk drive resources needed by the VMs (Fedora disk image, cloud-init files) are put inside `~/libvirt-storage-pool-openshift/`.

As we’re using the `qemu:///system` instance of libvirt, qemu will run with a specific `user:group` distinct from your user. It is configured in `/etc/libvirt/qemu.conf`. That qemu user must have access to that libvirt storage pool.

If your `$HOME` is world readable, everything is fine. If your `$HOME` is private, `ansible` will fail with an error message like:

```
error: Cannot access storage file '$HOME/libvirt-storage-pool-openshift/lenaic-master-216d8.qcow2' (as uid:99, gid:78): Permission denied
```

In order to fix that issue, you have several possibilities:
* set `libvirt_storage_pool_path` inside `playbooks/libvirt/openshift-cluster/launch.yml` and `playbooks/libvirt/openshift-cluster/terminate.yml` to a directory:
  * backed by a filesystem with a lot of free disk space
  * writable by your user;
  * accessible by the qemu user.
* Grant the qemu user access to the storage pool.

On Arch:

```
setfacl -m g:kvm:--x ~
```

Test the setup
--------------

```
cd openshift-ansible

bin/cluster create -m 1 -n 3 libvirt lenaic

bin/cluster terminate libvirt lenaic
```