Release Overview

• TrueNAS 27 RC.1 is the first release candidate of the next major TrueNAS version.
• Previously developed as TrueNAS 26.
• Final TrueNAS 27.0 release is planned for early December 2026.
• Core platform:
  • OpenZFS 2.4
  • Linux kernel 6.18

TrueSearch & WebShare

• TrueSearch
  • Server-side indexing of filenames, metadata, and file contents.
  • Provides fast searches across large NAS datasets.
  • Integrates with macOS Spotlight over SMB.
  • Avoids clients having to crawl network shares themselves.
• WebShare
  • Browser-based access to SMB/NFS-compatible files.
  • Works from desktops, tablets, and phones.
  • Preserves existing ACLs and permissions.
  • Supports file previews, snapshots, sharing, and file collection.
  • Integrates with Active Directory.
• Both features require TrueNAS Connect.

Fusion Pools 2.0

• Expands ZFS hybrid flash/HDD storage capabilities.
• Special vdevs can now use RAIDZ, rather than being limited to mirrors.
• Flash special vdevs can accelerate:
  • Metadata
  • Small files
  • Selected datasets
• A special vdev can also participate in the ZFS intent log (ZIL) for synchronous writes.
• A dedicated SLOG still takes priority when available.

Live Dataset Tiering

• Available in TrueNAS Enterprise.
• Transparently moves data blocks between:
  • High-performance flash storage
  • Larger HDD capacity tiers
• Migration occurs without disrupting connected clients.

Stateful SMB Failover

• Available on TrueNAS Enterprise HA systems.
• SMB session state survives controller failover.
• Clients no longer need to reconnect or re-authenticate after failover.
• Interrupted large file transfers can continue instead of restarting.

OpenZFS 2.4 Improvements

• Up to 25% faster deduplication writes.
• Faster encryption on CPUs with AVX2.
• Improved write allocation to reduce fragmentation.
• Better responsiveness as pools become full.
• Adds:
  • Default user quotas
  • Group quotas
  • Project quotas
  • Time-window scheduling for scrubs

Linux 6.18 & Containers

• Updated hardware support, including:
  • Broadcom tri-mode HBAs
  • PCIe Gen5 switching
  • New NVIDIA GPUs
• LXC containers are now fully supported, after being experimental in earlier TrueNAS releases.

TrueNAS Object Interface

• New Early Access feature.
• Provides native S3-compatible access directly to ZFS datasets.
• Available across TrueNAS editions.
• Can coexist with SMB, NFS, Active Directory, and WebShare access.

https://www.truenas.com/blog/truenas-27-rc1-feature-set