Debug

Error, problem, troubleshooting

Error	Event	Consequence	Cause	Remedy
`mount: /mnt/sys: sys already mounted on /mnt/sys` `dmesg(1) may have more information after failed mount system call.` `==> ERROR: failed to setup chroot /mnt/`	On exit	Cannot `chroot` again.		Manually unmount: `umount /mnt/dev/`, `umount /mnt/proc/`, `umount /mnt/sys/`.