When you boot a Centos server, it defaults to showing a splash screen when booting. You can press escape to switch to a more verbose boot mode. This article describes how to set verbose as the default boot mode.

Booting Centos in verbose mode

Login as the root user en edit the Grub menu.

# vi /boot/grub/menu.lst

It will show something like this:

title CentOS (2.6.32-431.20.5.el6.x86_64)
        root (hd0,0)
        kernel /vmlinuz-2.6.32-431.20.5.el6.x86_64 ro root=/dev/mapper/vg00-lv01 rd_NO_LUKS  KEYBOARDTYPE=pc KEYTABLE=us LANG=en_US.UTF-8 rd_NO_MD rd_LVM_LV=vg00/lv01 rd_LVM_LV=vg00/lv00 crashkernel=auto SYSFONT=latarcyrheb-sun16 rd_NO_DM rhgb quiet
        initrd /initramfs-2.6.32-431.20.5.el6.x86_64.img

The word “rhgb” is responsible for showing the splash screen. Simply remove it, save the file and reboot to get a verbose output instead of a splash screen while booting. If you want even more verbose output, also remove the word “quiet”. This will show more messages, some of which might be cryptic in nature.