XBD(4)

📦 version 11.0, in nixpkgs unstable

🧚 XBD(4) — from the xen Kernel Interfaces Manual: Xen frontend paravirtualized block device interface 🧚

✨ NAME ✨

xbd — Xen frontend paravirtualized block device interface. That's the name, that's the vibe, periodt. 💅

🎀 SYNOPSIS 🎀

xbd* at xenbus?

🌸 DESCRIPTION 🌸

Okay so xbd is the frontend part of the paravirtualized drivers that Xen guest domains use to have a block device interface. It's giving "your guest domain deserves a storage moment," and honestly? It ate. ✨

From a guest point of view, xbd is similar to a hard disk. You can treat it in the very same way when it comes to partitioning, file systems creation and usage, and mounting. By default, a NetBSD guest domain will assume that xbd0a serves as the root file system. The default just walked in and said "I'm the main character," and we respect it. 🫶

When the host is NetBSD, the xbd interface is backed by a xbdback(4) interface. In the XenStore, xbd and xbdback are identified by vbd (virtual block device) entries. iykyk. 🦋

💀 DIAGNOSTICS 💀

Here are the messages xbd can hit you with, plus what they mean:

  • xbd%d: using event channel %d — Specifies the event channel used by this xbd interface. It's literally telling you which channel it's using. ⭐
  • xbd%d: %s MB, %d bytes/sect x %u sectors — Gives the total size of the xbd block device, its sector size and total number of sectors. All the numbers, no cap. 🔥
  • xbd%d: WARNING: cache flush not supported by backend — The backend driver associated with this xbd device does not support cache flushing operation. This can be problematic for file system operations that require cache sync to avoid data loss or corruption. ⚠️
The cache flush warning is the one to take seriously, bestie: data loss or corruption is not a cute look. 💀

🔎 SEE ALSO 🔎

xbdback(4), xenbus(4), dkctl(8). Go read those too, bestie. 🫶

⏳ HISTORY ⏳

The xbd driver first appeared in NetBSD 3.0. A whole icon from the archives. 👑

👑 AUTHORS 👑

The xbd driver was written by Manuel Bouyer <bouyer@NetBSD.org>. Respect the legend. 💜

Cute sign-off: this page's footer says Debian, dated January 8, 2011, and the page is XBD(4). Mwah, bestie. 💋

📦 where this page comes from