I have install my fc6 server with RAID-1 software on 2 SATA HD. All work fine. My question is: If HD1 crash, HD2 is ready for boot the system? I have see witch the MBR of the 2 disk is different. (see follow explanation)... I must copy with this command: # dd bs=512 count=1 if=/dev/sda of=/dev/sdb MBR of first disk on MBR of second disk? Or this operation is not necessary? Many thanks! > [root@s-scarwall ~]# dd bs=512 count=1 if=/dev/sda of=/tmp/sda > 1+0 records in > 1+0 records out > 512 bytes (512 B) copied, 0,0119784 seconds, 42,7 kB/s > [root@s-scarwall ~]# dd bs=512 count=1 if=/dev/sdb of=/tmp/sdb > 1+0 records in > 1+0 records out > 512 bytes (512 B) copied, 0,0175179 seconds, 29,2 kB/s > [root@s-scarwall ~]# diff /tmp/sd? > Binary files /tmp/sda and /tmp/sdb differ > [root@s-scarwall ~]# hexdump -C /tmp/sda>/tmp/sda.txt > [root@s-scarwall ~]# hexdump -C /tmp/sdb>/tmp/sdb.txt > [root@s-scarwall ~]# diff /tmp/sd?.txt > 5c5 > < 00000040 80 00 00 80 41 24 02 00 00 08 fa 90 90 f6 c2 80 |....A$..........| > --- > > 00000040 81 00 00 80 41 24 02 00 00 08 fa 90 90 f6 c2 80 |....A$..........| > 28c28 > < 000001b0 00 00 00 00 00 00 00 00 21 d0 00 00 00 00 80 01 |........!.......| > --- > > 000001b0 00 00 00 00 00 00 00 00 bf 7e 08 00 00 00 80 01 |.........~......| > [root@s-scarwall ~]# > -- Dario Lesca <d.lesca@xxxxxxxxxx>