echo "- - -" > /sys/class/scsi_host/host0/scan
then fdisk, mkfs, etc.
hat tip: http://jcollie.blogspot.com/2008/05/how-to-re-scan-scsi-bus-on-linux.html

This was the only thing on the Fox network for a few glorious moments of product placement nirvana.
To paraphrase David Letterman’s self-deprecating joke, this was the only thing on the Fox network — a full frame plug for Cisco’s “Self-Defending Network” marketing messaging and this accompanying dialogue:
Bill: “Has it done any damage yet?”
Chloe: “No, the Cisco system is self-defending.”
Cisco even maintains a page to this clip and others — mostly Telepresence.
Thanks to Brad Reese’s Network World blog post for the pointer.
Try this first:
# dmidecode -s system-serial-number
The “-s” option didn’t work on the Kernel 2.4-based ESX service console, but this should:
# dmidecode | grep --extended-regexp Serial[[:space:]]Number:[[:space:]]*[A-Z0-9]{7}$ | uniq
Credit to Noah@Noah.org