Add a job for custom drain scripts

[benjaminguttmann-avtq]

Hi everyone,

I am aware of the discussion within #64, but I still want to bring up adding a custom drain script job to os-conf release. Our current use case is that we have environments where we are asked to install e.g. certain security agents, which we normally install via the pre-start or post-deploy hook.

Nevertheless, some of those agents we install tend to hold the disk hostage after everything has been already stopped and therefore cause issues, e.g. if we try to scale disks.

Therefore we would really like to add a job to configure a custom drain hook to ensure that the agents are actually stopped and do not prevent any further actions on the VM/ disk.

[benjaminguttmann-avtq]

@rkoster @nouseforaname maybe some opinions from your side.. I am also open for different approaches for our use case

[nouseforaname]

Why not create a skeleton release for the various agents based on os-conf? This release then has all the lifecycle hooks available and can be applied as an addon? I think this is a cleaner solution (with minimal adittional effort) as hijacking os-conf for this.

[rkoster]

I would also recommend to just create a release for your agent. With a pre-start and a drain script. If you consider it to much overhead to set up a blobstore for such a small release I would recommend take a look at git LFS: https://www.starkandwayne.com/blog/bosh-releases-with-git-lfs/

[rkoster]

Closing due to inactivity, feel free to reopen when needed.