lsof

Network Port

What process is using the port 50000

lsof -i :50000



lsof -i :https



lsof -i tcp:25



lsof -i udp:53



lsof -i :1-1024



lsof -i udp

Mount Point

What process is using the mount-point

lsof | grep /path/to/mount-point



lsof +f -- /path/to/dir



lsof +D /path/to/dir



# List all NFS files

lsof -N

Process

What files and directories are using by the process

lsof -p `pidof <app_name>`



lsof -c apache



lsof | grep apache



# list Parent PID of processes

lsof -p [PID] -R

User

# List files opened by processes belonging to a specific user

lsof -u [user-name]



lsof -a -i -u www-data

IP & Domain

List files based on their Internet address

# For IPv4

lsof -i 4



# For IPv6

lsof -i 6

File

lsof -t [file-name]

lsof -t /usr/lib/x86_64-linux-gnu/libpcre2-8.so.0.9.0

# Finding open files in a specific directory under Linux or Unix
lsof +D /path/to/dir/

# list any open files which have been removed or deleted
lsof -nP +L1
lsof -nP +L1 +D /path/to/dir/

Memory

lsof -d mem