Mix the mezcal, lime juice, soda and Sriracha sauce in a large pitcher. Stir well and add a few ice cubes.

Pour a layer of salt onto a small plate. Onto another small plate, squeeze enough lime juice to wet the top rims of the serving glasses. And, one by one, gently dip the top rims of the glasses first into the lime juice, then into the salt to coat. Add a few ice cubes to each glass and pour the cocktail.