Issue

• Unable to create filesystem on newly created volume. Problem persisted past a reboot.

# mke2fs -j -m 1 /dev/sdb1  
mke2fs 1.39 (29-May-2006)  
/dev/sdb1 is apparently in use by the system; will not make a filesystem here!

• I created a iscsi based LUN in RHEL 6.7,and I can find it by fdisk -l. I use fdisk to format the IPSAN from /dev/sde as /dev/sde1.
• I am checking the information, then I use pvcreate /dev/sde1 it replies:

Device /dev/sde1 not found (or ignored by filtering)

• I use mkfs.ext4 /dev/sde1 it replies:

/dev/sde1 is apparently in use by the system; will not make a filesystem here!