Hi everybody, some days ago I asked for help, becouse I got 'read_ahead not set' in /proc/mdstat. Now I understood the problem mainly due to incorrecty application of inattentive application of the HOWTO. I'll write my mistakes for the benefit of other people that in future may search for the answer in the archives: Of course I didn't do all this in a sudden, I managed to make all permutations ;-) 0. I used mkraid from raidtool 0.41 and reading instructions from 0.90 1. I used modules for raid1, but forgot to 'modprobe raid1'. 2. I switched to persistent-superblock but didn't set 'autodetect of RAID arrays' in the kernel (really, w/ 2.2.13 from Slackware there is no such entry, I had to generate the kernel w/ 2.2.14 from Red-Hat, but I sow is present also in 2.2.12 from Red-Hat ?!?) If you don't have autodetect you *NEED* 'raidstart', RedHat issue that automatically from rc.sysinit, Slackware doesn't. thanks to all who helped and pointed out documents. sandro *:-) PS. What does the patch do? I didn't apply the patch, and it worked, is that becouse RedHat has already applied the patch? (guess that's why 2.13 didn't have RAID autodetect...). Why isn't the patch in the kernel directly? -- Sandro Dentella *:-) e-mail: [EMAIL PROTECTED] [EMAIL PROTECTED]