The docs do not state that enabling "at-least-once" enables disk buffers

From the vector documentaiton: [1]

"in order to achieve at-least-once delivery between restarts, your sink must be configured to use disk-based buffers:"   


[1] - https://vector.dev/docs/about/under-the-hood/guarantees/#at-least-once 

always    

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User dont understand they are enabling disk bufffers  

Users understand disk buffers are being enabled.