M27: make backup checksums portable

deploy/unraid/backup-postgres.sh

@@ -22,7 +22,8 @@ docker compose -p "$project" $compose_files exec -T db sh -eu -c \
 docker compose -p "$project" $compose_files exec -T db pg_restore --list \
   < "$temporary_file" > /dev/null
 mv "$temporary_file" "$backup_file"
-sha256sum "$backup_file" > "${backup_file}.sha256"
+(cd "$destination" && \
+  sha256sum "$(basename "$backup_file")" > "$(basename "$backup_file").sha256")
 BACKUP_RETENTION_DAYS="$retention_days" BACKUP_MINIMUM_COPIES="$minimum_copies" \
   ./deploy/unraid/prune-postgres-backups.sh "$destination"
 trap - EXIT INT TERM

deploy/unraid/scheduled-backup.sh

@@ -21,7 +21,7 @@ while true; do
       --host=db --username="$POSTGRES_USER" "$POSTGRES_DB" > "$temporary" \
       && pg_restore --list "$temporary" > /dev/null; then
     mv "$temporary" "$target"
-    sha256sum "$target" > "$target.sha256"
+    (cd "$destination" && sha256sum "$(basename "$target")" > "$(basename "$target").sha256")
     if [ -n "$secondary" ]; then
       cp "$target" "$target.sha256" "$secondary/"
     fi