Is sandbox down?

We purged all the data on sandbox a few months ago. You'll have to re-create your account.

Do I need also to create again all the test data?

Yes. Sorry. We were unable to retrieve the data.

How will be done next time? I would like to avoid again a complete killing. Is just testing data (to avoid using production one of course)

An odd series of events led to the loss of sandbox data. It was running on a VM that is no longer supported.

We re-built sandbox on an EC2 instance so, barring a catastrophic EC2 failure we shouldn't lose sandbox data again.

We make no guarantees about the uptime or resiliency of sandbox though. Sandbox exists as a test environment for Geni and our users.