1. A method for execution by one or more processing modules of one or more computing devices of a dispersed storage network (DSN), the method comprises: ascertaining a decode threshold value for dispersed storage error encoding data for storage in storage units of the DSN, wherein the decode threshold value corresponds to a minimum number of encoded data slices of a set of encoded data slices needed to recover a data segment of the data, wherein the data segment was dispersed storage error encoded into the set of encoded data slices; determining a total width value for the dispersed storage error encoding based on the decode threshold value, a number of selected sites within the DSN, and a number of selected storage units of the selected sites, wherein the total width value is greater than the decode threshold value and corresponds to a number of encoded data slices in the set of encoded data slices; determining logical storage slots within the selected storage units of the selected sites based on the total width value, the number of selected sites within the DSN, and the number of selected storage units of the selected sites; and writing the set of encoded data slices to a total width value of the logical storage slots within at least some of the selected storage units of the selected sites based on a slice-to-slot mapping, wherein the slice-to-slot mapping allows for a site failure number of the selected sites to fail and still be able to retrieve the decoded threshold value of encoded data slices from one or more of the selected storage units of remaining selected sites of the selected sites.