lsns

lists information about Linux namespaces

TLDR

List all namespaces

$ lsns

List namespaces in JSON format

$ lsns -J

List namespaces for a specific process

$ lsns -p 1234

List only specific type of namespaces

$ lsns -t net

List with custom columns

$ lsns -o NS,TYPE,PID,COMMAND

List persistent namespaces only

$ lsns -P

SYNOPSIS

lsns [options] [namespace]

DESCRIPTION

lsns lists information about Linux namespaces. Namespaces provide isolation for various system resources, and this tool displays which namespaces exist and which processes are using them.

PARAMETERS

-t, --type TYPE

Filter by namespace type (mnt, net, ipc, user, pid, uts, cgroup, time)

-p, --task PID

Show namespaces for specific process

-o, --output LIST

Specify columns to display

-l, --list

Use list output format

-J, --json

Output in JSON format

-r, --raw

Use raw output format

-n, --noheadings

Do not print headers

-u, --notruncate

Do not truncate text in columns

-W, --nowrap

Do not wrap multi-line cells

-P, --persistent

Show only persistent namespaces

-T, --tree REL

Show tree view with specified relationship

NAMESPACE TYPES

mnt: Mount pointsnet: Network resourcesipc: System V IPC objectsuser: User and group IDspid: Process IDsuts: Hostname and domaincgroup: Cgroup root directorytime: Boot and monotonic clocks

CAVEATS

Non-root users may see incomplete results as some namespace information requires elevated privileges. The default output format may change between versions; use explicit options for scripts.

HISTORY

lsns is part of util-linux, providing visibility into the Linux namespace subsystem used for containerization and process isolation.