HI,   This is my first mail to this mailing list.I want to block external usb storage completly on my  server running on centos 5 having confidiential data.  For that i used udev and blocked the external usb storage by creating the udev rule  mentioning any usb storage will get mounted to /dev/null so that users cant mount as well.   But in the mean time i am getting below log in my /var/log/messages file when i insert any usb storage device. ###################################################### May 23 12:24:02 localhost kernel: usb 1-4: new high speed USB device using ehci_hcd and address 4 May 23 12:24:02 localhost kernel: usb 1-4: configuration #1 chosen from 1 choice May 23 12:24:02 localhost kernel: scsi3 : SCSI emulation for USB Mass Storage devices May 23 12:24:07 localhost kernel: scsi 3:0:0:0: Direct-Access     USB      Flash Disk       1100 PQ: 0 ANSI: 0 CCS May 23 12:24:07 localhost kernel: sd 3:0:0:0: [sdb] 1981440 512-byte hardware sectors (1014 MB) May 23 12:24:07 localhost kernel: sd 3:0:0:0: [sdb] Write Protect is off May 23 12:24:07 localhost kernel: sd 3:0:0:0: [sdb] Assuming drive cache: write through May 23 12:24:07 localhost kernel: sd 3:0:0:0: [sdb] 1981440 512-byte hardware sectors (1014 MB) May 23 12:24:07 localhost kernel: sd 3:0:0:0: [sdb] Write Protect is off May 23 12:24:07 localhost kernel: sd 3:0:0:0: [sdb] Assuming drive cache: write through May 23 12:24:07 localhost kernel:  sdb: sdb1 May 23 12:24:07 localhost kernel: sd 3:0:0:0: [sdb] Attached SCSI removable disk May 23 12:24:07 localhost kernel: sd 3:0:0:0: Attached scsi generic sg2 type 0 ##############################################  I  want to know how  device name sdb1[see above log] was allocated and is it possible to block the device node creation,if so wht i can do to block the same in my messages log. Regards lingu