Provided by: podman_3.4.4+ds1-1ubuntu1.22.04.3_amd64 bug

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-cni
       Join  the  rootless  network  namespace  used for CNI networking. It can be used to connect to a rootless
       container via IP address (CNI  networking).  This  is  otherwise  not  possible  from  the  host  network
       namespace.  Note: Using this option with more than one unshare session can have unexpected results.

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

       Exit code contained command exit code

              $ podman run busybox /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-cni 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-mount(1), namespaces(7), newuidmap(1), newgidmap(1), user_namespaces(7)

                                                                                             podman-unshare(1)()