Like dust under a bad the god Billowed and rolled towards us what type of speech is this alliteration or any other

What does the line rage, rage against the dying of the light from the poem "do not go gentle into that good night" have in common with the line ride the six hundred from the poem "the change of the light brigade? "a. they end each stanzab. they are repetitious linesc. they end a sestetd. they begin an octave