NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda      8:0    0 465.8G  0 disk 
├─sda1   8:1    0   100M  0 part 
├─sda2   8:2    0 194.6G  0 part 
├─sda3   8:3    0     1K  0 part 
├─sda5   8:5    0 255.1G  0 part 
└─sda6   8:6    0  15.9G  0 part [SWAP]
sdb      8:16   1     2G  0 disk 
└─sdb1   8:17   1     2G  0 part /cdrom
sdc      8:32   0 931.5G  0 disk 
├─sdc1   8:33   0   100M  0 part 
├─sdc2   8:34   0 194.6G  0 part /media/ubuntu/D0ACEEBEACEE9E6A
├─sdc3   8:35   0     1K  0 part 
├─sdc5   8:37   0 255.1G  0 part /media/ubuntu/8842230d-31cc-48c8-9df3-27705abc8
└─sdc6   8:38   0  15.9G  0 part 
loop0    7:0    0 962.1M  1 loop /rofs
ubuntu@ubuntu:~$ sudo umount /media/ubuntu/8842230d-31cc-48c8-9df3-27705abc8
umount: /media/ubuntu/8842230d-31cc-48c8-9df3-27705abc8: not found