Troubleshooting
"Too many open files"
Cause: Your system's file descriptor limit is too low for the number of tasks you're running.
Fix: Increase the limit. See Scaling & System Tuning for step-by-step instructions for macOS and Linux.
Quick temporary fix:
ulimit -n 100000
kasper-cli
"Cannot connect to host: nodename nor servname provided"
Cause: DNS resolution failure. The target hostname couldn't be resolved.
Fix:
Verify the queue URL is correct and the domain resolves:
nslookup your-queue-domain.com
Check that your DNS resolver is working (try nslookup google.com)
If using proxies, confirm the proxy server can resolve the target domain
"Event loop is closed"
Cause: Python's asyncio event loop was shut down unexpectedly, usually due to mixing sync and async code.
Fix: This is normally handled automatically by Kasper. If it persists:
Make sure you're running the latest version (kasper-cli update)
If using the programmatic API, ensure you're calling asyncio.run() only once and not mixing it with synchronous blocking calls
Tasks stuck in "active" state
Cause: The queue server may be slow or unresponsive, or your proxies are timing out.
Fix:
Check that the queue URL is still live in a browser
Try increasing timeout in your config
If using proxies, test them independently, a few bad proxies can stall tasks assigned to them
Kasper won't start after update
Cause: The Python virtual environment may be corrupted.
Fix: Reinstall:
For MacOS:
For Windows:
This creates a fresh virtual environment and installs the latest version.
If none of the above solves your issue, reach out through the official support channels with:
Your Kasper version (kasper-cli --version)
Whether you're using proxies (and how many)
