The output of
ls -l /sys/block/*/device should give you an idea about how each device is connected to the system.
In the example below
red is a virtual disk on an internal RAID controller,
green is a CD-ROM connected via an IDE controller, and
the rest are SAN-connected SCSI disks where "hostN" refers to the instance of the Host Bus Adapter they are connected to.
Code:
# ls -l /sys/block/*/device
lrwxrwxrwx 1 root root 0 Sep 19 02:11 /sys/block/cciss!c0d0/device -> ../../devices/pci0000:00/0000:00:04.0/0000:0d:00.0/disk0
lrwxrwxrwx 1 root root 0 Sep 19 02:11 /sys/block/hda/device -> ../../devices/pci0000:00/0000:00:1f.1/ide0/0.0
lrwxrwxrwx 1 root root 0 Sep 18 14:58 /sys/block/sda/device -> ../../devices/pci0000:00/0000:00:02.0/0000:13:00.0/host0/target0:0:0/0:0:0:0
lrwxrwxrwx 1 root root 0 Sep 18 14:58 /sys/block/sdb/device -> ../../devices/pci0000:00/0000:00:02.0/0000:13:00.0/host0/target0:0:0/0:0:0:1
lrwxrwxrwx 1 root root 0 Sep 18 14:58 /sys/block/sdc/device -> ../../devices/pci0000:00/0000:00:02.0/0000:13:00.0/host0/target0:0:0/0:0:0:64
lrwxrwxrwx 1 root root 0 Sep 18 14:58 /sys/block/sdd/device -> ../../devices/pci0000:00/0000:00:02.0/0000:13:00.0/host0/target0:0:0/0:0:0:120
...
