Dear Maintainer, I added a 30 GB mSATA SSD to my system some time ago and yesterday moved my Debian GNU/Linux Sid installation to it. First I tried UEFI which failed like in 720513. I will add my findings there. Then I told gdisk to make a hybrid MBR, then deleted the GPT partition and well redid all other partitions so the start from partition one and told gdisk to zap all GPT structures. Then I installed grub-pc 2.00-17 from chroot for both /dev/sda and /dev/sdb. On reboot I got: Welcome to GRUB! error: disk ',gpt2' not found. Entering rescue mode... grub rescue> help Unknown command 'help' grub rescue> insmod help error: disk ',gpt2' not found. At this point I consider its not worth trying anything else to get the system to boot. I booted into GRML 2013.2 64-Bit and reinstalled GRUB. I also remade device.map once via grub-mkdevicemap I think. I grepped to ,gpt2 in grub configuration – all to no avail. Finally I disabled the new mSATA SSD in BIOS. Then it booted from the MBR of the old Intel SSD 320 and it used my new GRUB configuration from the system I copied to the mSATA SSD. Today I upgraded to 2.00-18. And I made sure its on both disks: merkaba:~> grub-install /dev/sda installation beendet. Keine Fehler aufgetreten. merkaba:~> grub-install /dev/sdb installation beendet. Keine Fehler aufgetreten. merkaba:~> grub-install "(hd0)" /usr/sbin/grub-bios-setup: Fehler: Laufwerk »hd0« wurde nicht gefunden.. merkaba:~#1> grub-mkdevicemap merkaba:~> grub-install /dev/sda installation beendet. Keine Fehler aufgetreten. merkaba:~> grub-install /dev/sdb installation beendet. Keine Fehler aufgetreten. merkaba:~> grub-install "(hd0)" installation beendet. Keine Fehler aufgetreten. merkaba:~> grub-install "(hd1)" installation beendet. Keine Fehler aufgetreten. merkaba:~> martin@merkaba:~> cat /boot/grub/device.map (hd0) /dev/disk/by-id/ata-INTEL_SSDSA2CW300G3_SERIAL-OF-INTEL-SSD-320 (hd1) /dev/disk/by-id/ata-INTEL_SSDMCEAC030B3_SERIAL-OF-MSATA-SSD hd0 is old Intel SSD 320 (300 GB) hd1 is new Intel mSATA SSD (30 GB) Result: GRUB doesn´t boot if mSATA SSD appears before old Intel SSD 320 in boot order. Its fails with aforementioned error message. Expected result: GRUB just boots. No matter which MBR the BIOS will take. Any idea? I just use LVM on the Intel SSD 320. On the mSATA SSD I just use partitions. merkaba:~> lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 279,5G 0 disk ├─sda1 8:1 0 4M 0 part ├─sda2 8:2 0 191M 0 part ├─sda3 8:3 0 286M 0 part └─sda4 8:4 0 279G 0 part ├─merkaba-swap (dm-0) 254:0 0 12G 0 lvm [SWAP] ├─merkaba-debian (dm-1) 254:1 0 18,6G 0 lvm └─merkaba-home (dm-2) 254:2 0 243,5G 0 lvm sdb 8:16 0 28G 0 disk ├─sdb1 8:17 0 200M 0 part ├─sdb2 8:18 0 300M 0 part /boot └─sdb3 8:19 0 20G 0 part sr0 11:0 1 1024M 0 rom merkaba:~> fdisk -l /dev/sdb Disk /dev/sdb: 30.0 GB, 30016659456 bytes 255 heads, 63 sectors/track, 3649 cylinders, total 58626288 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Device Boot Start End Blocks Id System /dev/sdb1 2048 411647 204800 ef EFI (FAT-12/16/32) /dev/sdb2 411648 1026047 307200 83 Linux /dev/sdb3 1026048 42969087 20971520 83 Linux Thanks, Martin