I accidentially overwrote the first 1M of my harddisk on linux (using dd). So, the partition-table is gone. I can still access all partition (except the first one) using /dev/sda2 (and so on), so the data is still there. I only need the partition boundaries to restore the table. How can I do this? The Linux-Kernel must still know them because all mount-points still work.
fdisk -l /dev/sda doesn't work because it acctualy reads the partition table.