1. The website tier still showed up as first tier in the column data center tier in Application Health Dashboard (those area highlighed in the screenshot) although the website tier didn't checked as 'make front-end tier'. Why is that?
Also, there are actually second and third question I want to ask:
2. It seems like the tier (the one circled in blue) is somehow showing in the wrong order?
3. I would like to know why the tier (the one pointed by black arrow) is showing 'data center status is not available' ?
Maybe there are some other tiers defined based on software services? In this case you'll have multiple icons with the "website" icon if these software services are webservices.
This might also be the reason the icon is showing up in the first column.
Answering your third question:
Coloring status for icons in all columns, except Network, relates to Primary metric. I don't know which primary metric you have selected, but, for example, if Application performance is selected as Primary metric:
then icons are colored based on Application performance threshold:
How is threshold configured? You can check that and modified it:
If threshold type is 'benchmark' (like for Operation/Transaction time metric) than metric value is compared with baseline value, so, sometimes if no baseline is available, then an icon appears gray.
As far as I understand (correct me if I am wrong), if the front-end tier is not configured, then all the data-center-tier icons wouldn't showed up here. But this doesn't seems to be the case here:
You can see that only one tier has the "Front-End Tier" append to the tier name/description when I hover the mouse to the icon. (The same goes for other business application too, where website always)
As I am still scratching my head on this, would it be possible that SS-based tier and analyzer-based tier can't coexist together? I am thinking the next thing to try might be disable/delete all analyzer-based tier and use only SS-based tier.