Not a sunny greeting? (3,4)

I believe the answer is:

all hail

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'greeting?' is the definition.
(I've seen this before)

I don't understand the remainder of the clue.

(Other definitions for all hail that I've seen before include "Appalling weather" , "' ---, Macbeth!' (Each witch)" , "that may greet one" , "dire weather forecast" , "that greeted Macbeth" .)

I've seen this clue in The Globe and Mail.

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