Webinar Overview
Join Allan Jude, Co-founder and Head of Solutions Architecture at Klara Inc., and Jim Salter, Creator of Sanoid and Co-host of the 2.5 Admins Podcast, for a festive wrap-up to the year with The 12 Days of ZFS.
In this special session, they will share twelve practical tips, tricks, and hidden gems that help you get the most out of ZFS—from performance tuning and troubleshooting to snapshots and replication.
Think of it as a stocking full of sysadmin treats: useful insights you can put to work right away, plus a look at what’s coming next for ZFS in the new year.
What You’ll Learn:
- Managing a free space reserve
- Expanding snapshot retention using bookmarks
- Where is all of this activity coming from
- Leaving breadcrumbs for your future self
Top Questions from the Session—Answered!
🗨️ Is the .zfs/snapshot directory enough to verify consistency?
To properly confirm that a local snapshot matches a replicated one, the most dependable method is to compare the respective snapshot's GUIDs. If the GUIDs match, the snapshots are identical—no need to rely on comparing files or modified dates in .zfs/snapshot.
🗨️ Are vdevs like metadata or special vdevs still relevant when using all-flash/SSD storage?
If the flash to be used for the special/metadata vdev is the same as the primary storage devices there are limited benefits outside some specific use cases.
Special/metadata vdevs need to be very high endurance and very low latency, whereas throughput isn't a key factor. If a higher class of NVMe device is used for the special vdev, it can provide a strong benefit, especially for small blocks or metadata. This can be doubly true when the main SSDs use larger sector sizes (16+ KB).
🗨️ How can ZFS snapshots be exposed to Windows as Shadow Copies over SMB?
Interoperability with Windows Volume Shadow Copies is configured within Samba. The requirement is that snapshots must be named such that Samba can parse the date out of the snapshot name. It is easiest to achieve this by using exactly the date format Windows expects, the libc strftime specifier of: `%Y.%m.%d-%H.%M.%S`. With the correct naming pattern in place, enabling the vfs_shadow_copy2 module in Samba will expose the snapshots of individual files to Windows as "Previous Versions".
Date: December 10, 2025
Time: 11:00 AM EST
Duration: 50 minutes.
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Meet the Hosts
Co-Founder and Head of Solutions Architecture at Klara Inc., Allan Jude has been on the team since the beginning. Shepherding an amazing team of developers and sysadmins, he is the technical heart of our team. A core ZFS developer, FreeBSD contributor, and author of FreeBSD Mastery: ZFS, Allan is a community go-to person for ZFS and open source through and through. He enjoys spending his time improving ZFS, advancing FreeBSD, and making open source code better.
Learn About Klara
Jim Salter (@jrssnet) is an author, public speaker, mercenary sysadmin, and father of three—not necessarily in that order. He got his first real taste of open source by running Apache on his very own dedicated FreeBSD 3.1 server back in 1999, and he’s been a fierce advocate of FOSS ever since. He’s the author of the Sanoid hyperconverged infrastructure project and co-host of the 2.5 Admins podcast.
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