Developer Guide and Troubleshooting
===================================

This section aims to explain in more detail the steps that Apex follows
to make a deployment. It also tries to explain possible issues you might find
in the process of building or deploying an environment.

After installing the Apex RPMs in the jumphost, some files will be located
around the system.

1.  /etc/opnfv-apex: this directory contains a bunch of scenarios to be
    deployed with different characteristics such HA (High Availability), SDN
    controller integration (OpenDaylight/ONOS), BGPVPN, FDIO, etc. Having a
    look at any of these files will give you an idea of how to make a
    customized scenario setting up different flags.

2.  /usr/bin/: it contains the binaries for the commands opnfv-deploy,
    opnfv-clean and opnfv-util.

3.  /var/opt/opnfv/: it contains several files and directories.

   3.1.   images/: this folder contains the images that will be deployed
   according to the chosen scenario.

   3.2.   lib/: bunch of scripts that will be executed in the different phases
   of deployment.


Utilization of Images
---------------------

As mentioned earlier in this guide, the Undercloud VM will be in charge of
deploying OPNFV (Overcloud VMs). Since the Undercloud is an all-in-one
OpenStack deployment, it will use Glance to manage the images that will be
deployed as the Overcloud.

So whatever customization that is done to the images located in the jumpserver
(/var/opt/opnfv/images) will be uploaded to the undercloud and consequently, to
the overcloud.

Make sure, the customization is performed on the right image. For example, if I
virt-customize the following image overcloud-full-opendaylight.qcow2, but then
I deploy OPNFV with the following command:

        ``sudo opnfv-deploy -n network_settings.yaml -d
        /etc/opnfv-apex/os-onos-nofeature-ha.yaml``

It will not have any effect over the deployment, since the customized image is
the opendaylight one, and the scenario indicates that the image to be deployed
is the overcloud-full-onos.qcow2.


Post-deployment Configuration
-----------------------------

Post-deployment scripts will perform some configuration tasks such ssh-key
injection, network configuration, NATing, OpenVswitch creation. It will take
care of some OpenStack tasks such creation of endpoints, external networks,
users, projects, etc.

If any of these steps fail, the execution will be interrupted. In some cases,
the interruption occurs at very early stages, so a new deployment must be
executed. However, some other cases it could be worth it to try to debug it.

        1.  There is not external connectivity from the overcloud nodes:

                Post-deployment scripts will configure the routing, nameservers
                and a bunch of other things between the overcloud and the
                undercloud. If local connectivity, like pinging between the
                different nodes, is working fine, script must have failed when
                configuring the NAT via iptables. The main rules to enable
                external connectivity would look like these:

                ``iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE``
                ``iptables -t nat -A POSTROUTING -s ${external_cidr} -o eth0 -j
                MASQUERADE``
                ``iptables -A FORWARD -i eth2 -j ACCEPT``
                ``iptables -A FORWARD -s ${external_cidr} -m state --state
                ESTABLISHED,RELATED -j ACCEPT``
                ``service iptables save``

                These rules must be executed as root (or sudo) in the
                undercloud machine.

OpenDaylight Integration
------------------------

When a user deploys any of the following scenarios:

        - os-odl_l2-bgpvpn-ha.yaml
        - os-odl_l2-fdio-ha.yaml
        - os-odl_l2-fdio-noha.yaml
        - os-odl_l2-nofeature-ha.yaml
        - os-odl_l2-sfc-noha.yaml
        - os-odl_l3-nofeature-ha.yaml

OpenDaylight (ODL) SDN controller will be deployed too and completely
integrated with OpenStack. ODL is running as a systemd service, so you can
manage it as a regular service:

        ``systemctl start/restart/stop opendaylight.service``

This command must be executed as root in the controller node of the overcloud,
where OpenDaylight is running. ODL files are located in /opt/opendaylight. ODL
uses karaf as a Java container management system that allows the users to
install new features, check logs and configure a lot of things. In order to
connect to Karaf's console, use the following command:

        ``opnfv-util opendaylight``

This command is very easy to use, but in case it is not connecting to Karaf,
this is the command that is executing underneath:

        ``ssh -p 8101 -o UserKnownHostsFile=/dev/null -o
        StrictHostKeyChecking=no karaf@localhost``

Of course, localhost when the command is executed in the overcloud controller,
but you use its public IP to connect from elsewhere.

Debugging Failures
------------------

This section will try to gather different type of failures, the root cause and
some possible solutions or workarounds to get the process continued.

1.  I can see in the output log a post-deployment error messages:

        Heat resources will apply puppet manifests during this phase. If one of
        these processes fail, you could try to see the error and after that,
        re-run puppet to apply that manifest. Log into the controller (see
        verification section for that) and check as root /var/log/messages.
        Search for the error you have encountered and see if you can fix it. In
        order to re-run the puppet manifest, search for "puppet apply" in that
        same log. You will have to run the last "puppet apply" before the
        error. And It should look like this:

                ``FACTER_heat_outputs_path="/var/run/heat-config/heat-config-puppet/5b4c7a01-0d63-4a71-81e9-d5ee6f0a1f2f"  FACTER_fqdn="overcloud-controller-0.localdomain.com" \
                FACTER_deploy_config_name="ControllerOvercloudServicesDeployment_Step4"  puppet apply --detailed-exitcodes -l syslog -l console \
                /var/lib/heat-config/heat-config-puppet/5b4c7a01-0d63-4a71-81e9-d5ee6f0a1f2f.pp``

        As a comment, Heat will trigger the puppet run via os-apply-config and
        it will pass a different value for step each time. There is a total of
        five steps. Some of these steps will not be executed depending on the
        type of scenario that is being deployed.