Your Lab Tenant and Personal Tenant
Every account has two tenants of its own: a Lab Tenant, where labs run, and a Personal Tenant, which is yours to set up however you like.
Your tenants
The account menu lists every tenant you belong to. Your Lab Tenant comes first, then your Second Lab Tenant once a lab needs one, then your Personal Tenant, then any other tenant with your place in it, Owner or Administrator. Choose one to open its management pages.
The Lab Tenant
Your Lab Tenant is named Lab Photos unless you rename it. A new account's Lab Tenant is set up for the lab of the first lesson, What is Identity?, when the account is created. An older account's is set up the next time its account menu loads, and the menu shows it as Setting up until it appears.
You are its Tenant Admin. Each lab step links the management page where that change is made, and you can explore every other page too. Labs that need a second identity provider add a Second Lab Tenant, named Lab Mail.
What Start does
Pressing Start on a lab page rebuilds your Lab Tenant as a new tenant set up exactly as that lab expects, so you can do labs in any order. Anything you changed there before is gone, and the tenant's own Audit starts again. Request Logs and the records of earlier Starts stay visible until their 30 days of retention end. Its address stays the same.
A Lab Tenant has no Reset of its own: starting a lab again is how you get a fresh one. It is also cleared after 30 days with no Start and no use of its management pages, and the next Start builds it again.
Your Personal Tenant
No lab rebuilds your Personal Tenant. Use it for anything you want to keep, or to try what a lab taught with settings of your own.
Which tenant opens
Open by default on the Account tab of your profile chooses whether the account menu and tenant management open your Lab Tenant or your Personal Tenant. A change applies at once in the browser you made it in. Another browser keeps opening the tenant it opened last until you choose one in its menu.
Audit and limits
Changes you make in your Lab Tenant appear in its Audit with you as the actor. The setup for your first lab is recorded there as the lab-setup tenant service, because nobody pressed Start, and in your account activity as First lab setup in your Lab Tenant. In a troubleshooting lab, the change that Begin the incident applies appears as Lab case automation, so you can tell it apart from your own repair.
Your profile's Usage tab shows how often you can change Open by default and how many lab environments you can build each hour. The first lab's setup counts as one build.