Hello, I have a Promise EX 12-port RAID controller in my box, connected to 8 750GB disks. I have set up 2 RAID-5 devices and joined these using LVM. This is working fine. However, there is something that seems wrong.. (4-1) * 750 = 2250, but df reports the LVM volume as a mere 4.0T; /dev/mapper/storage_volume-stor 4.0T 3.6T 507G 88% /storage Shouldn't this be 4.5TB? Relevant bit of boot log: scsi4 : stex Vendor: Promise Model: 4 Disk RAID5 Rev: 1.10 Type: Direct-Access ANSI SCSI revision: 02 sdb : very big device. try to use READ CAPACITY(16). SCSI device sdb: 4395053952 512-byte hdwr sectors (2250268 MB) sdb: Write Protect is off sdb: Mode Sense: 00 12 00 00 SCSI device sdb: drive cache: write back sdb : very big device. try to use READ CAPACITY(16). SCSI device sdb: 4395053952 512-byte hdwr sectors (2250268 MB) sdb: Write Protect is off sdb: Mode Sense: 00 12 00 00 SCSI device sdb: drive cache: write back sdb: sdb1 sd 4:0:0:0: Attached scsi disk sdb sd 4:0:0:0: Attached scsi generic sg1 type 0 Vendor: Promise Model: 4 Disk RAID5 Rev: 1.10 Type: Direct-Access ANSI SCSI revision: 02 sdc : very big device. try to use READ CAPACITY(16). SCSI device sdc: 4395053952 512-byte hdwr sectors (2250268 MB) sdc: Write Protect is off sdc: Mode Sense: 00 12 00 00 SCSI device sdc: drive cache: write back sdc : very big device. try to use READ CAPACITY(16). SCSI device sdc: 4395053952 512-byte hdwr sectors (2250268 MB) sdc: Write Protect is off sdc: Mode Sense: 00 12 00 00 SCSI device sdc: drive cache: write back sdc: sdc1 sd 4:0:4:0: Attached scsi disk sdc sd 4:0:4:0: Attached scsi generic sg2 type 0 Vendor: Promise Model: RAID Console Rev: 1.00 Type: Processor ANSI SCSI revision: 03 scsi 4:0:16:0: Attached scsi generic sg3 type 3 -- Cheers, Morten :wq