When working with Linux systems, you'll often need to identify which physical partition contains a particular directory. This is crucial for:

• Disk space management
• Filesystem maintenance
• Partition resizing operations
• Understanding storage architecture

The most straightforward solution is using the df command with the directory path:

df -h /path/to/directory

Example output:

Filesystem      Size  Used Avail Use% Mounted on
/dev/nvme0n1p2  100G   45G   55G  45% /home

Using stat for Filesystem Information

For more detailed filesystem information:

stat -f -c %T /path/to/directory

Checking Mount Options

To see mount options for a partition:

findmnt -n -o OPTIONS --target /path/to/directory

Here's a bash function to display all relevant partition information:

#!/bin/bash

function show_partition_info() {
    local dir=$1
    echo "===== Partition Information for $dir ====="
    df -h $dir | tail -n +2
    echo -e "\nFilesystem type:"
    stat -f -c %T $dir
    echo -e "\nMount options:"
    findmnt -n -o OPTIONS --target $dir
}

show_partition_info "/var/log"

Special scenarios to consider:

• Bind mounts (mount --bind)
• Overlay filesystems
• Network filesystems (NFS, CIFS)
• Virtual filesystems (proc, sysfs)

For these cases, you might need:

findmnt -T /path -o SOURCE,TARGET,FSTYPE,OPTIONS

When querying frequently (e.g., in monitoring scripts):

• Cache results where possible
• Use df -P for predictable parsing
• Consider /proc/mounts for low-level access

When managing Linux systems, administrators often need to identify the underlying storage partition for specific directories. This is crucial for:

Disk space monitoring and management
Filesystem maintenance operations
Performance troubleshooting
Storage capacity planning



The most straightforward solution is using the df command with the directory path:
df -h /path/to/directory

Example output:
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda2        50G   15G   33G  32% /home

For more detailed information, consider these approaches:
# 1. Using stat command
stat -c %m /path/to/directory

# 2. Combining findmnt with df
findmnt -n -o SOURCE --target /path/to/directory

# 3. For LVM volumes
lsblk -o NAME,MAJ:MIN,RM,SIZE,RO,FSTYPE,MOUNTPOINT /path/to/directory

Here's how to implement this in scripts:
#!/bin/bash
TARGET_DIR="/var/log"
PARTITION=$(df --output=source "$TARGET_DIR" | tail -n 1)
echo "Directory $TARGET_DIR is on partition $PARTITION"


For bind mounts: Use findmnt -o TARGET,SOURCE
For network filesystems: Check mount output
For chroot environments: Prepend chroot /path/to/chroot

When dealing with large directory structures:
# Faster alternative for recursive checks
time df --output=source /deep/nested/path >/dev/null