Last Updated: 2025-10-30

• Stands for "diagnostic message"
• The output of this command typically contains the messages produced by the DEVICE DRIVERS.
• Fetches all the messages from the kernel's buffer.
• Run with sudo $ sudo dmesg
• The format of each message is usually DEVICE NAME : MESSAGE. The message will be in a format determined by its particular driver.

Use cases

1. Check after plugging in a USB device to determine if it was recognized
2. Check if a particular device had its bus enumerated during boot and/or check what parameters they were set up with

Relationship to syslog? Only the fact that it may sent its messages to syslog for centralization.