compose multi tier applications on tacker

Hi Pedro:
    Is the requirement that the first server be up and running before the 2nd one can be deployed? Or is it simply that the IP address of the first server is available for the second server to use in its configuration?

The first scenario would require a higher-level orchestrator to monitor the deployment, but the second scenario can use the existing heat dependency mechanisms to make the second VDU dependent on the IP address availability of the first.

If the config (user_data) section of the second VDU uses a get_attr function to retrieve the IP address from the port of the first VDU, it should solve the second scenario.

Hope this helps

Hi Bob,

yes that's a requirement, for example when is a DB Server, it needs to be up running.

I know that this is supported in heat through SoftwareConfig directive, see this template as an example: https://github.com/openstack/heat-templates/blob/master/hot/software-config/example-templates/wordpress/WordPress_software-config_2-instances.yaml

Since tacker is "heat compatible" I wonder if this is possible to use it here, using this SoftwareConfig method.

Your thoughts?

Thanks

Bob,

another thing to try is the second method and have some kind of monit daemon on the second VDU that keeps trying to start the service until the DB is up and running.

Regards

You could look at some of the example/test templates in the heat-translator repository to see if there are any that are similar to what you want to do:

https://github.com/openstack/heat-translator/tree/master/translator/tests/data

There are several example templates that use SoftwareConfig and might be able to provide a sample.

Thanks Bob,

are these templates compatible with tacker?

Hi Bob,

yes these examples are related with I intend to do, but don't seem to be compatible with tacker.

Do I need to convert them and how could this be done?

Thanks