E: Sub-process returned an error code" During APT Upgrade: A Deep Dive into Cache and List Corruption
Solving E: Sub-process returned an error code During APT Upgrade: A Deep Dive into Cache and List Corruption" The frustrating error, E: Sub-process returned an error code, completely cripple the apt package manager. My own extensive troubleshooting revealed the root cause wasn't a problematic package, but rather a failing package manager hook specifically tied to etckeeper. Recently, I encountered this exact issue on a server running on Linux Ubuntu 24.04 server while attempting to upgrade elasticsearch fleet node. Cleanup of APT's local cache and package lists does not work. 1. The Symptoms and The Misleading Logs The problem was I could not perform any package transaction (install, remove, or upgrade), with the error appearing immediately after files were downloaded but before installation started. Failure Point: The system exited with E: Sub-process returned an error code. Failed Debugging: Standard troubleshooting (dpkg --configure -a, checking term.log, and even jou...