Remote agent on Pi Zero - Fails to start

Trying to run - pio remote agent start on a Pi Zero fails.

The following is part of the error.

It takes a very longtime to get to this point. Maybe a few hours.

Building wheel for cryptography (PEP 517) ... error
  ERROR: Command errored out with exit status 1:
   command: /usr/bin/python3 /tmp/ build_wheel /tmp/tmpw4cld6du
       cwd: /tmp/pip-install-bfoky9x7/cryptography_ad3b2f62ff8641f3be82c24c95dd43c0
  Complete output (168 lines):
  running bdist_wheel
  running build
  running build_py
  creating build
  creating build/lib.linux-armv6l-3.9
  creating build/lib.linux-armv6l-3.9/cryptography


pip install cryptography

Works without failure so I think I have all the required dependiences.

Pio Remote errors with this message:

 running build_ext
  running build_rust
      =============================DEBUG ASSISTANCE=============================
      If you are seeing a compilation error please try the following steps to
      successfully install cryptography:
      1) Upgrade to the latest pip and try again. This will fix errors for most
         users. See:
      2) Read for specific
         instructions for your platform.
      3) Check our frequently asked questions for more information:
      4) Ensure you have a recent Rust toolchain installed:
      Python: 3.9.2
      platform: Linux-5.10.63+-armv6l-with-glibc2.31
      pip: n/a
      setuptools: 59.2.0
      setuptools_rust: 0.12.1
      =============================DEBUG ASSISTANCE=============================
  error: can't find Rust compiler
  If you are using an outdated pip version, it is possible a prebuilt wheel is available for this package but pip is not able to install from it. Installing from the wheel would avoid the need for a Rust compiler.
  To update pip, run:
      pip install --upgrade pip
  and then retry package installation.
  If you did intend to build this package from source, try installing a Rust compiler from your system package manager and ensure it is on the PATH during installation. Alternatively, rustup (available at is the recommended way to download and update the Rust compiler toolchain.
  This package requires Rust >=1.41.0.
  ERROR: Failed building wheel for cryptography
Successfully built pyopenssl
Failed to build cryptography

Any Ideas?


Hmm I thought @ivankravets had pinned the cryptography version to be at the one that didn’t require the Rust compiler in HowTo: Raspberry Pi 3 as remote agent (Oct. 2020) - #17 by ivankravets. Can you do a pio upgrade --dev to make sure you have the latest version, then retry?

1 Like

Please upgrade to the latest PlatformIO Core.

Hi Ivan & Max

Thanks I though I had but will try now and report back