https://community.cloudera.com/t5/Support-Questions/ext3-or-ext4-or-xfs/m-p/50266#M44297 <P>Hello Igor, &nbsp;<BR /><BR />To create a partition in Linux, you’d need to ‘fdisk’ it first. In your example, (sdb) is the disk, so you’d need to to create the partition (sdb1):<BR /><BR /></P><PRE>fdisk /dev/sdb</PRE><P><BR />After that, you’d need to format the new partition into an ext4:</P><P>&nbsp;</P><PRE>mkfs.ext4 /dev/sdb1</PRE><P><BR />Make sure you are mount it correctly in /etc/fstab, just like I stated in my first response, ‘mount -a’ command is a good way to examine your fstab entries.<BR /><BR />In regards to the HDFS block size, the block division in HFDS is just logically built over the physical blocks of the ext4 filesystem; HDFS blocks are large compared to disk blocks, and the reason for this is to minimize the cost of seeks. If the block is large enough, the time it takes to transfer the data from the disk can be significantly longer than the time to seek to the start of the block.<BR /><BR />If there are any additional questions, please let me know.<BR /><BR />Thanks,</P><P><BR />Laith</P> Wed, 01 Feb 2017 20:59:54 GMT Laith 2017-02-01T20:59:54Z