8b040810_el_Boot_Parameters___DataBook___2
[0] quiet [1] Kernel [2] 
Suppresses verbose output messages from the kernel during boot. The kernel messages will be saved in the kernel ring buffer whether this parameter is present or not so you can still view them if there is a problem during kernel initialization. The kernel ring buffer can be displayed using the dmesg command.
Kernel Boot Parameters | DataBook®
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