Fabric Classic

1.21.0 verified Fri May 01 auth: no python

fab-classic is a maintained fork of the original Fabric 1.x line, providing a simple, Pythonic tool for remote execution and deployment via SSH. The current version is 1.21.0, with quarterly releases and support for Python 3.5+.

pip install fab-classic

Common errors

error ImportError: No module named fabric.api ↓

cause Installed Fabric 2+ (fabric3) instead of fab-classic.

fix

Uninstall fabric/fabric3 and install fab-classic: pip uninstall fabric; pip install fab-classic.

error paramiko.ssh_exception.SSHException: Error reading protocol banner ↓

cause Network issue or server drops connection early.

fix

Increase timeout or retry: env.timeout = 30; env.connection_attempts = 3.

error TypeError: _pty_size() got an unexpected keyword argument 'height' ↓

cause Incompatible with Python 3.14 (struct buffer size change).

fix

Upgrade to fab-classic>=1.20.2.

Warnings

breaking Python 2.7 support dropped in 1.20.0 ↓

fix Upgrade to Python 3.5+ or pin fab-classic<1.20.0.

gotcha Parallel mode may hang on macOS Python 3.8+ without explicit fork context. Use env.parallel = True with caution. ↓

fix Set multiprocessing context to 'fork': import multiprocessing as mp; mp.set_start_method('fork') before using --parallel.

deprecated paramiko-ng is no longer supported by default; use upstream paramiko. ↓

fix Ensure paramiko (not paramiko-ng) is installed.

gotcha local() capture behavior changed in 1.19.0; failing commands with capture=False no longer raise SystemExit. ↓

fix Check return code explicitly if using capture=False.

Imports

run
wrong
```
from fabric import run
```
correct
```
from fabric.api import run
```
Fabric 2/3 uses 'from fabric import Connection'; classic uses fabric.api.

Quickstart

Minimal remote command execution using fabric.api.

from fabric.api import run, env, cd
env.host_string = 'example.com'
env.user = 'user'
with cd('/var/www'):
    run('ls -la')
run('uname -a')