how to check the filesystem type of a logical volume
Same as you would with any other block device. e.g.
file -s /dev/vg1/lv1
If it's ext4, it'll say something like:
/dev/vg1/lv1: Linux rev 1.0 ext4 filesystem data, UUID=xxxx, volume name "yyyy" (needs journal recovery) (extents) (large files) (huge files)
Alternatively, you could run blkid /dev/vg1/lv1
. That would report something like:
/dev/vg1/lv1: LABEL="yyyy" UUID="xxxx" TYPE="ext4"
From man file
:
-s, --special-files
Normally, file only attempts to read and determine the type of argument files which stat(2) reports are ordinary files. This prevents problems, because reading special files may have peculiar consequences. Specifying the -s option causes file to also read argument files which are block or character special files.
This is useful for determining the filesystem types of the data in raw disk partitions, which are block special files. This option also causes file to disregard the file size as reported by stat(2) since on some systems it reports a zero size for raw disk partitions.
Use lsblk -f
.
$ lsblk -f
NAME FSTYPE LABEL UUID FSAVAIL FSUSE% MOUNTPOINT
sda
├─sda1 ext4 d2123fec-6c94-426f-b505-8cf3441122cf 742,6M 17% /boot
└─sda2 LVM2_member BLt1F3-S5E3-hBRX-Eqya-AUOx-wyxc-a5Yaf4
├─fedora-root xfs 59935050-8e89-4f7f-bf0f-2f448c4c680b 12,8G 15% /
└─fedora-swap swap 5fbca8c7-fd22-4acf-a411-d96a100c8ab2 [SWAP]
sr0 iso9660 VBox_GAs_6.0.8 2019-05-13-13-58-35-65