Yearly Archives: 2024


Executing a Cron Job Within an Anaconda Environment

For those seeking to automate their Python scripts using cron jobs within an Anaconda environment, there’s a straightforward method to ensure your scripts run under the correct environment. This approach involves leveraging the capabilities of bash and the configuration of your cron environment to recognize and activate the necessary Anaconda environment. Here’s how to set it up:

  1. Export Anaconda Initialization to a Dedicated Configuration File First, isolate the Anaconda initialization snippet from your ~/.bashrc file by copying it to a new file, say ~/.bashrc_for_cron. This step ensures the cron environment can source the necessary configurations to activate Anaconda environments. Make sure that:
  • The file is readable by the user scheduling the cron job.
  • The file is secured against write access from other users to mitigate security risks.
  1. Configure Cron to Use Bash and Source the Anaconda Configuration Edit your crontab configuration by running crontab -e and prepend your cron jobs with two crucial lines:
   SHELL=/bin/bash
   BASH_ENV=~/.bashrc_for_cron

These lines configure cron to execute jobs using bash instead of the default sh shell and to source the Anaconda configurations from ~/.bashrc_for_cron. When invoked by cron, this setup ensures that bash is aware of the necessary environment to activate Anaconda environments.

  1. Activate Anaconda Environment Before Executing Your Script When scheduling your Python script in crontab -e, prefix the command with the conda activate instruction to switch to your desired Anaconda environment. For instance, to run a script at 12:30 AM every day within a specific Anaconda environment, your cron job entry would look like:
   30 0 * * * conda activate opencv_env; python /path/to/script.py

This ensures that the script executes within the context of the specified Anaconda environment, opencv_env, leveraging any dependencies or configurations defined within that environment.

By following these steps, you can seamlessly schedule and run Python scripts under specific Anaconda environments, leveraging cron’s scheduling capabilities while ensuring the correct environment and dependencies for your scripts.


Various problems with legacy SSH systems

Case 1

Unable to negotiate with 192.168.1.1 port 22: no matching key exchange method found. Their offer: diffie-hellman-group1-sha1

We solved this problem using the following command:

ssh -oKexAlgorithms=+diffie-hellman-group1-sha1 [email protected];

Case 2

ssh -oKexAlgorithms=+diffie-hellman-group1-sha1 [email protected];
Unable to negotiate with 192.168.1.1 port 22: no matching host key type found. Their offer: ssh-rsa,ssh-dss

We solved this problem using the following command:

ssh -oKexAlgorithms=+diffie-hellman-group1-sha1 -oHostKeyAlgorithms=+ssh-dss [email protected];