lxc-unshare - Online in the Cloud

PROGRAM:

NAME

lxc-unshare - Run a task in a new set of namespaces.

SYNOPSIS

lxc-unshare {-s namespaces} [-u user] [-H hostname] [-i ifname] [-d] [-M] {command}

DESCRIPTION

lxc-unshare can be used to run a task in a cloned set of namespaces. This command is
mainly provided for testing purposes. Despite its name, it always uses clone rather than
unshare to create the new task with fresh namespaces. Apart from testing kernel
regressions this should make no difference.

OPTIONS

-s namespaces
Specify the namespaces to attach to, as a pipe-separated list, e.g. NETWORK|IPC.
Allowed values are MOUNT, PID, UTSNAME, IPC, USER and NETWORK. This allows one to
change the context of the process to e.g. the network namespace of the container
while retaining the other namespaces as those of the host. (The pipe symbol needs
to be escaped, e.g. MOUNT\|PID or quoted, e.g. "MOUNT|PID".)

-u user
Specify a userid which the new task should become.

-H hostname
Set the hostname in the new container. Only allowed if the UTSNAME namespace is
set.

-i interfacename
Move the named interface into the container. Only allowed if the NETWORK namespace
is set. You may specify this argument multiple times to move multiple interfaces
into container.

-d Daemonize (do not wait for the container to exit before exiting)

-M Mount default filesystems (/proc /dev/shm and /dev/mqueue) in the container. Only
allowed if MOUNT namespace is set.

EXAMPLES

To spawn a new shell with its own UTS (hostname) namespace,

lxc-unshare -s UTSNAME /bin/bash

If the hostname is changed in that shell, the change will not be reflected on the host.

To spawn a shell in a new network, pid, and mount namespace,

lxc-unshare -s "NETWORK|PID|MOUNT" /bin/bash

The resulting shell will have pid 1 and will see no network interfaces. After re-mounting
/proc in that shell,

mount -t proc proc /proc

ps output will show there are no other processes in the namespace.

To spawn a shell in a new network, pid, mount, and hostname namespace.

lxc-unshare -s "NETWORK|PID|MOUNT|UTSNAME" -M -H slave -i veth1 /bin/bash

The resulting shell will have pid 1 and will see two network interfaces (lo and veth1).
The hostname will be "slave" and /proc will have been remounted. ps output will show there
are no other processes in the namespace.

Use lxc-unshare online using onworks.net services