troubleshoot when import cluster fails

[ltrilety]

There should be some troubleshoot guide with instructions what can be done if cluster import is not successful e.g. some node is missing etc.

It will be good if there will be described some way how to remove cluster from tendrl.

[julienlim]

@ltrilety @nthomas-redhat @Tendrl/tendrl-core @Tendrl/qe
+1. I think we need to also put together the list of failure modes we've observed to-date regarding import failures, as this will help populate what to put in the "Messages" tab in the UI.

[r0h4n]

Currently known failures are due to:

• Package install failure (network or node issue)
• Node.status goes DOWN during import
• Problems with configuring collectd and tendrl collectd plugins

@Tendrl/tendrl-core @shtripat @GowthamShanmugam @julienlim @Tendrl/tendrl-qe comments?

[shtripat]

@r0h4n +1