Since KVM@TACC now requires bounded reservations, VM instances and their data are deleted when reservations end. While snapshots can preserve entire instances, persistent volumes offer a more flexible solution for storing experiment scripts and data that persists independently of your VM lifecycle. This guide walks through creating volumes via the GUI, partitioning and mounting storage, and extending volumes as your storage needs grow.

This past month brings 2025 to a close and also exciting updates, including a year in review, Trovi improvements, and a CHI@Edge artifact, along with announcements about upcoming webinars (next up: How to Organize Artifact Evaluations (AEs) with Shared Infrastructure on Jan. 13th), our call for presentations for our sixth user meeting at NCAR’s campus in Boulder, and highlights from our newly appointed reproducibility ambassadors.

As we approach the holiday season, we’d like to thank you once again for being a part of our wonderful Chameleon community!

Please keep in mind the following adjustments in our schedule over the next few weeks:

• The Chameleon Help Desk will be closed from Wednesday, December 24 until January 5th.

• As tradition, between December 19 to the 23rd, we’ll permit you to make 14-day leases for nodes and VMs that typically have 7-day limits.

This month brings exciting updates including enhanced hardware browser integration, CHI@Edge stability improvements, and expanded support for distributed training on AMD GPUs, along with announcements about upcoming webinars and our sixth user meeting at NCAR’s campus in Boulder.

Trovi helps you package and share computational artifacts that run on Chameleon, from Jupyter notebooks to complete experimental workflows. Whether you're importing code from GitHub, organizing artifacts into Collections, collaborating with co-authors, or publishing work to get a citable DOI, these tips will help you make the most of Trovi for your research and teaching.

Not sure whether to use bare metal or KVM for your next Chameleon experiment? You're not alone. With KVM's recent addition of H100 GPUs and advance reservations, the choice isn't always obvious. This comprehensive comparison walks you through the practical trade-offs: when you need the isolation of bare metal for accurate benchmarking, when KVM's 6-month leases and resource sharing make more sense, and how to navigate the different storage and networking options. Make informed infrastructure decisions that accelerate your research.

This month we have some exciting updates to Trovi’s dashboard, support for 4xGPU instances on KVM@TACC, improvements to cc-snapshot, and a new webinar series!

New H100 hardware on KVM@TACC, and good news about KVM lease limits, quotas, and SU cost. Additionally, we have SU changes for baremetal, an improved the resource browser, and are announcing the deprecation of TACC login.

This month, we have a significant change to KVM@TACC: as per our announcement last month, all KVM instance launches will now require an advance reservation step in the allocation workflow (with the “advance” potentially being once second from now, i.e., on demand). Also, we have cool new hardware on CHI@Edge, and improvements to the “message of the day” on Chameleon-supported base images

This month we have changes to KVM@TACC that allow you to launch any VM flavor from a reservation, which soon will be required. In a few months, we’ll shut down VMs that aren’t from a lease, so make sure to check out the details! We’ve extended python-chi with better support for KVM, adding methods for flavor reservation, managing security groups, and volumes.