Re-read the partitions without rebooting

Couple of Ways
1. partprobe
2. hdparm -z /dev/sdX
3. blockdev –rereadpt /dev/disk
4. echo 1 > /sys/block/sdc/device/rescan

http://www.cyberciti.biz/tips/re-read-the-partition-table-without-rebooting-linux-system.html