Operate Apps

Usual operator actions covered in this chapter are:

• Assess the state of the cluster and its hosted applications, troubleshoot warnings, post-mortem analysis.
• Start, stop, relocate one service or a selection of services to fix warning causes, prepare hardware or operating system maintenance

The chapter follows that order:

• Assess — reading cluster and service state, and the markers om mon uses to pack it densely.
• Resource Info — the key-values each resource publishes about what it is made of.
• Select — naming the objects you want to act on, from one path to an expression matching many.
• Action — running the action, and what to do when it fails.