Raito Bezarius
33eaaf02fd
The pre-flight `echo started` check over SSH was originally added in577ebeaefb. As it is usual with these old commits, understanding why is there a need for something is difficult. The closest thing would be > Fix a race starting the SSH master. We now wait synchronously for > the SSH master to finish starting. This prevents the SSH clients > from starting their own connections. But, we removed SSH connection sharing, so this does not apply anymore. Nonetheless, we believed this check was meant as a way to catch obvious misconfigurations or SSH failures early, before handing off to `nix-store`. However, this approach was not fruitful: it assumes the remote has a `bash`-compatible shell, `echo` behaves in a standard way, and no `ForceCommand` interferes—all of which are unreliable assumptions in practice. While the intent was to provide slightly better diagnostics (e.g. in case of SSH hanging or returning an interactive shell), in practice it does not meaningfully catch or improve real failure cases. The underlying protocol or engine can and should handle those errors more robustly anyway. In contrast, this check *does* break several legitimate workflows, including: * remote builders using `ForceCommand` wrappers (e.g. `nix-remote-build`-style setups), see <https://discourse.nixos.org/t/wrapper-to-restrict-builder-access-through-ssh-worth-upstreaming/25834/15>, * SSHing into minimal environments lacking `bash` (e.g. initrd, busybox-based systems), * configurations that don’t default to POSIX-like shells, e.g., nushell enthusiasts. As such, we’re removing this code. Protocol mismatch errors and SSH failures can be rethought and handled more structurally elsewhere in the engine. Change-Id: I187f6881375d42ef83987a13a350c97964bbdb30 Signed-off-by: Raito Bezarius <raito@lix.systems> (cherry picked from commit0dd8bf6c1c)
Lix
Lix is an implementation of Nix, a powerful package management system for Linux and other Unix systems that makes package management reliable and reproducible.
Read more about us at https://lix.systems.
Installation
On Linux and macOS the easiest way to install Lix is to run the following shell command (as a user other than root):
$ curl -sSf -L https://install.lix.systems/lix | sh -s -- install
For systems that already have a Nix implementation installed, such as NixOS systems, read our install page
Building And Developing
See our Hacking guide in our manual for instruction on how to set up a development environment and build Lix from source.
Additional Resources
- The Lix reference manual:
- Our wiki
- Matrix - #space:lix.systems
License
Lix is released under LGPL-2.1-or-later.