Hybrid model¶

The flagship Rubin Science Platform (RSP) at data.lsst.cloud is a hybrid deployment, with services and data distributed across multiple data centers:

Most of the services and some data are hosted on the Google Cloud Platform.
A few services and most of the data are hosted at our US Data Facility (USDF) at SLAC.

Together, these make up the US Data Access Center.

The hybrid architecture of data.lsst.cloud

This architecture provides flexibility and performance while controlling storage costs. However, it can make understanding the system’s behavior during outages challenging. Read on to understand what to expect when USDF/SLAC is offline and how to continue using the RSP during such outages.

Outages¶

When an outage occurs, service and data availability can be affected differently depending on which data access center is impacted.

Service availability during a USDF (SLAC) outage¶

The following table shows service availability when data.lsst.cloud is operational but USDF/SLAC is experiencing an outage:

Service	DP1	DP0.3	DP0.2
TAP (catalogs)	❌	❌	❌
HIPS	✅	❌	❌
SIA (images)	✅	❌	❌
SODA (cutouts)	✅	❌	❌
ObsTAP (images)	❌	❌	❌

What you can do during a USDF/SLAC outage¶

Access the Notebook aspect
Use services marked with ✅ above
Analyze previously retrieved data
Access services from external archives

Portal functionality during a USDF/SLAC outage¶

The following image shows which Portal tabs remain functional during a USDF/SLAC outage:

Working portal tabs

Tip

If your portal does not look like the above image, you can configure the visible tabs by using the “hamburger” menu on the top left.

Getting updates during a USDF/SLAC outage¶

During LSST Data Previews, the errors from RSP services may not always make it obvious what the issue is, so do monitor updates posted in banners on the data.lsst.cloud homepage. See Staying up to date for other ways to stay informed.