Troubleshooting section in OSSM Docs

This has been a persistent request. It's important because the tools you would use to troubleshoot OSSM are different from those you might use to troubleshoot Istio (e.g. istioctl). 

The format would be a list of problems people commonly encounter, with a sub list of things to check / try. They could be oc commands, odo commands, log lines to look for, things to try in the OpenShift Console or Kiali, SMCP settings to modify, etc.

It's probably worth a quick meeting with the engineering/qe teams to discuss what scenarios would make sense here.

Some Re-organization: Today, in the "Service Mesh Release Notes" page (Aside: this page has far more than release notes, and is an odd first page to introduce you to service mesh to start with - maybe "Service Mesh Overview"?), we have a section "Getting Support". Rather than directing people straight to support, we should direct them to a troubleshooting page at this point in the doc. At the end of the troubleshooting page, we can then have "Getting Support". 

Some potential use cases

• I deployed Service mesh, but now my services are not able to communicate.
• Why are Envoy side cars are not being injected into my application pods?
• etc...

We shouldn't aim to be exhaustive in this - even 2-3 scenarios with things to try would be a good starting point.

Some Questions that have come up:

• How can I verify that traffic is using mTLS between:
  • An Istio Gateway and a Service
  • Between two services
• Next Q...

ETA 4/13 - Neal and Julie chatted and agreed on a very loose general structure:

• Assembly (major buckets, these may change over time)
  • Installation
  • Control Plane
  • Envoy
  • Security
  • Service Communication
• Module (topic structure)
  • Heading – Customer visible symptom (What you saw)
  • Expected behavior (What’s it’s supposed to do)
  • Root cause of the issue (Why you saw it)
  • Diagnostic Steps (if any. Also, this section might appear before Root cause, if there are multiple possible causes)
  • Resolution  (How do I fix it)

QE POCs:

mmahoney@redhat.com for Kiali, gbaufake for Istio and jkandasa-rh for Jaeger - and fbrychta@redhat.com should be able to help review troubleshoot doc about OpenShift and OSSM in general.