A technique involves: in response to receiving a first request for adjusting a first width of a disk array to a second width, obtaining, based on source identification information of a source stripe group in the disk array in the first request, source block identification information of a source block associated with the source stripe group. The technique further involves: determining destination identification information of a destination stripe group associated with the second width for storing data. The technique further involves: storing, based on the source identification information and the destination identification information, source data and metadata for the source data from the source block into a destination block of the destination stripe group, the metadata including node identification information for accessing nodes of the source block. The technique further involves: adjusting the node to access the destination block based on the node identification information.