--- name: "libnbd-release-notes-1.8" section: "1" platform: "linux" package: "libnbd" version: "1.24.4-1" release: "Arch Linux 2026-11-01" platforms: ["linux"] url: "https://new.carta.tech/libnbd-release-notes-1.8" --- # libnbd-release-notes-1.8(1) release notes for libnbd 1.8 ## NAME libnbd-release-notes-1.8 - release notes for libnbd 1.8 ## DESCRIPTION These are the release notes for libnbd stable release 1.8. This describes the major changes since 1.6. libnbd 1.8.0 was released on **7 June 2021**. libnbd is now hosted on gitlab: https://listman.redhat.com/archives/libguestfs/2021-February/msg00021.html ### Security If you find a security issue, please read *SECURITY* in the source (online here: https://gitlab.com/nbdkit/libnbd/blob/master/SECURITY). To find out about previous security issues in libnbd, see [**libnbd-security**(3)](/libnbd-security/3.md). There was one security bug found in libnbd during this release cycle. *CVE-2021-20286 denial of service when using* ***nbd\_set\_opt\_mode****(3)* See the full announcement here: https://listman.redhat.com/archives/libguestfs/2021-March/msg00092.html (Found and fixed by Eric Blake). ### New APIs - [**nbd\_get\_private\_data**(3)](/nbd_get_private_data/3.md) - [**nbd\_set\_private\_data**(3)](/nbd_set_private_data/3.md) These calls allow you to store either an unsigned integer or a pointer in the handle for the application to use for its own purposes. - [**nbd\_get\_uri**(3)](/nbd_get_uri/3.md) This call constructs an NBD URI which can be used to connect back to the same server (using [**nbd\_connect\_uri**(3)](/nbd_connect_uri/3.md) or from other tools that support the NBD URI standard). ### Enhancements to existing APIs Numeric IPv6 URIs (like `"nbd://[::1]/"`) are now supported. libnbd gives a better error message if the server backlog overflows (thanks Xin Long, Lukas Doktor, Eric Blake, Martin Kletzander). ### New features Continuous integration (CI) tests now run on every commit and merge request to the upstream repository (Martin Kletzander). ### Tools A great deal of work has been done to improve the performance of [**nbdcopy**(1)](/nbdcopy/1.md) (Nir Soffer, Eric Blake). On Linux, nbdcopy now uses readahead when reading from files, and takes steps to preserve the host page cache. nbdcopy new *--request-size* option to allow controlling the size of requests made to NBD servers. Adjusting this can affect performance (Nir Soffer). nbdcopy now supports `"null:"` pseudo-target, where it discards the output. This is useful for benchmarking. nbdcopy new *-v* flag to enable libnbd and other debugging. [**nbdinfo**(1)](/nbdinfo/1.md) *--list* (which lists all exports of a server) no longer exits early if one of the exports is inaccessible or there is a recoverable error (Eric Blake). nbdinfo now prints the URI of each export in the output making it easier to connect back to each export. [**nbdfuse**(1)](/nbdfuse/1.md) is now multithreaded and supports issuing parallel NBD commands on a single connection as well as multi-conn, and other enhancements have been made. This resulted in around 50% performance improvement when tested with fio. nbdfuse now supports nbdcopy-style `"[ CMD ]"`, eg:\ nbdfuse dir/ramdisk \[ nbdkit memory 1G \] nbdfuse now supports trimming. Also it supports fast zeroing, but this requires a forthcoming kernel patch before it will work. nbdfuse sets the virtual file permissions appropriately if the NBD export is read-only. nbdfuse new *-v* flag to enable libnbd and other debugging. ### Tests Added a test of interoperability with [**qemu-storage-daemon**(1)](/qemu-storage-daemon/1.md). Note that qemu-storage-daemon was broken in qemu 6.0.0 so this test can fail unless you update to a fixed version (thanks Stefan Hajnoczi, Daniel Berrangé). Added a test of nbdcopy with TLS which was previously untested. Python code style tests are now opt-in using\ ./configure --enable-python-code-style More tests should now run on FreeBSD and not be skipped. nbdfuse tests now ensure that errors from NBD are transmitted through FUSE back to the local client. `"MALLOC_CHECK_"` and `"MALLOC_PERTURB_"` are only enabled when running the tests, not when running libnbd programs from the build directory. This makes it easier to do benchmarks. ### Other improvements and bug fixes The minimum C compiler is now ISO C99 (previously ANSI C90). FUSE 3 (instead of FUSE 2) is now required to build nbdfuse. The library tries harder not to leak thread-local storage memory on dlclose or exit. (Because of the design of Linux it is not always possible to avoid this, especially in multithreaded programs.) Fix the progress bar in [**nbdcopy**(1)](/nbdcopy/1.md). UTF-8 export names are now processed and displayed properly by [**nbdinfo**(1)](/nbdinfo/1.md). The *--help* output of nbdcopy, nbdfuse and nbdinfo now displays a brief summary of all options and has some examples. The generator now only requires ocamlc, not ocamlfind (Abhay Raj Singh). Golang bindings now use and require golang modules. ### Documentation Document using libnbd with the Meson build system. Added Python examples. Add example of how to integrate libnbd with libev (Nir Soffer). ## SEE ALSO [**libnbd**(3)](/libnbd/3.md). ## AUTHORS Eric Blake Richard W.M. Jones Martin Kletzander Nir Soffer ## COPYRIGHT Copyright Red Hat ## LICENSE This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA