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[root@collabn1 ~]# fdisk /dev/sdb Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel Building a new DOS disklabel. Changes will remain in memory only, until you decide to write them. After that, of course, the previous content won't be recoverable. Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite) Command (m for help): n Command action e extended p primary partition (1-4) p Partition number (1-4): 1 First cylinder (1-652, default 1): ^M [default] Using default value 1 Last cylinder or +size or +sizeM or +sizeK (1-652, default 652): Using default value 652 Command (m for help): t Selected partition 1 Hex code (type L to list codes): da Changed system type of partition 1 to da (Non-FS data) Command (m for help): w The partition table has been altered! WARNING: Re-reading the partition table failed with error 16: Device or resource busy. The kernel still uses the old table. Syncing disks.