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% podman-unshare(1)

## NAME
podman\-unshare - Run a command inside of a modified user namespace

## SYNOPSIS
**podman unshare** [*--*] [*command*]

## DESCRIPTION
Launches a process (by default, *$SHELL*) in a new user namespace. The user
namespace is configured so that the invoking user's UID and primary GID appear
to be UID 0 and GID 0, respectively.  Any ranges which match that user and
group in `/etc/subuid` and `/etc/subgid` are also mapped in as themselves with the
help of the *newuidmap(1)* and *newgidmap(1)* helpers.

**podman unshare** is useful for troubleshooting unprivileged operations and for
manually clearing storage and other data related to images and containers.

It is also useful if you want to use the **podman mount** command.  If an unprivileged user wants to mount and work with a container, then they need to execute
**podman unshare**.  Executing **podman mount** fails for unprivileged users unless the user is running inside a **podman unshare** session.

The unshare session defines two environment variables:

- **CONTAINERS_GRAPHROOT**: the path to the persistent container's data.
- **CONTAINERS_RUNROOT**: the path to the volatile container's data.

## OPTIONS

#### **--help**, **-h**

Print usage statement

#### **--rootless-netns**

Join the rootless network namespace used for CNI and netavark networking. It can be used to
connect to a rootless container via IP address (bridge networking). This is otherwise
not possible from the host network namespace.

## Exit Codes

The exit code from `podman unshare` gives information about why the container
failed to run or why it exited.  When `podman unshare` commands exit with a non-zero code,
the exit codes follow the `chroot` standard, see below:

  **125** The error is with podman **_itself_**

    $ podman unshare --foo; echo $?
    Error: unknown flag: --foo
    125

  **126** Executing a _contained command_ and the _command_ cannot be invoked

    $ podman unshare /etc; echo $?
    Error: fork/exec /etc: permission denied
    126

  **127** Executing a _contained command_ and the _command_ cannot be found

    $ podman unshare foo; echo $?
    Error: fork/exec /usr/bin/bogus: no such file or directory
    127

  **Exit code** _contained command_ exit code

    $ podman unshare /bin/sh -c 'exit 3'; echo $?
    3

## EXAMPLE

```
$ podman unshare id
uid=0(root) gid=0(root) groups=0(root),65534(nobody)

$ podman unshare cat /proc/self/uid_map /proc/self/gid_map
         0       1000          1
         1      10000      65536
         0       1000          1
         1      10000      65536

$ podman unshare --rootless-netns ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: tap0: <BROADCAST,UP,LOWER_UP> mtu 65520 qdisc fq_codel state UNKNOWN group default qlen 1000
    link/ether 36:0e:4a:c7:45:7e brd ff:ff:ff:ff:ff:ff
    inet 10.0.2.100/24 brd 10.0.2.255 scope global tap0
       valid_lft forever preferred_lft forever
    inet6 fe80::340e:4aff:fec7:457e/64 scope link
       valid_lft forever preferred_lft forever
3: cni-podman2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 5e:3a:71:d2:b4:3a brd ff:ff:ff:ff:ff:ff
    inet 10.89.1.1/24 brd 10.89.1.255 scope global cni-podman2
       valid_lft forever preferred_lft forever
    inet6 fe80::5c3a:71ff:fed2:b43a/64 scope link
       valid_lft forever preferred_lft forever
4: vethd4ba3a2f@if3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master cni-podman2 state UP group default
    link/ether 8a:c9:56:32:17:0c brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet6 fe80::88c9:56ff:fe32:170c/64 scope link
       valid_lft forever preferred_lft forever
```


## SEE ALSO
**[podman(1)](podman.1.md)**, **[podman-mount(1)](podman-mount.1.md)**, **namespaces(7)**, **newuidmap(1)**, **newgidmap(1)**, **user\_namespaces(7)**