How do I enable debugging in Linux?

Linux Agent – Enable Debug mode

1. # Enable Debug mode (comment or remove debug line to disable) Debug=1. Now restart the CDP Host Agent module:
2. /etc/init.d/cdp-agent restart. To test this you can ‘tail’ the CDP Agent log file to see the new [Debug] lines that are added to the logs.
3. tail /usr/sbin/r1soft/log/cdp.log.

How do you debug a kernel?

Setup

1. Build the kernel with CONFIG_GDB_SCRIPTS enabled, but leave CONFIG_DEBUG_INFO_REDUCED off. …
2. Install that kernel on the guest, turn off KASLR if necessary by adding “nokaslr” to the kernel command line. …
3. Enable the gdb stub of QEMU/KVM, either. …
4. cd /path/to/linux-build.
5. Start gdb: gdb vmlinux. …
6. Attach to the booted guest: