mirror of
https://github.com/containers/podman.git
synced 2025-06-23 02:18:13 +08:00
Merge pull request #10072 from eriksjolund/rewrite_uidmap_documenation
[CI:DOCS] Rewrite --uidmap doc in podman-create.1.md and podman-run.1.md
This commit is contained in:
OpenShift Merge Robot
@ -975,11 +975,71 @@ Remote connections use local containers.conf for defaults
|
||||
Set the umask inside the container. Defaults to `0022`.
|
||||
Remote connections use local containers.conf for defaults
|
||||
|
||||
#### **\-\-uidmap**=*container_uid:host_uid:amount*
|
||||
#### **\-\-uidmap**=*container_uid*:*from_uid*:*amount*
|
||||
|
||||
UID map for the user namespace. Using this flag will run the container with user namespace enabled. It conflicts with the `--userns` and `--subuidname` flags.
|
||||
Run the container in a new user namespace using the supplied mapping. This
|
||||
option conflicts with the **\-\-userns** and **\-\-subuidname** options. This
|
||||
option provides a way to map host UIDs to container UIDs. It can be passed
|
||||
several times to map different ranges.
|
||||
|
||||
The following example maps uids 0-2000 in the container to the uids 30000-31999 on the host and gids 0-2000 in the container to the gids 30000-31999 on the host. `--uidmap=0:30000:2000`
|
||||
The _from_uid_ value is based upon the user running the command, either rootful or rootless users.
|
||||
* rootful user: *container_uid*:*host_uid*:*amount*
|
||||
* rootless user: *container_uid*:*intermediate_uid*:*amount*
|
||||
|
||||
When **podman create** is called by a privileged user, the option **\-\-uidmap**
|
||||
works as a direct mapping between host UIDs and container UIDs.
|
||||
|
||||
host UID -> container UID
|
||||
|
||||
The _amount_ specifies the number of consecutive UIDs that will be mapped.
|
||||
If for example _amount_ is **4** the mapping would look like:
|
||||
|
||||
| host UID | container UID |
|
||||
| - | - |
|
||||
| _from_uid_ | _container_uid_ |
|
||||
| _from_uid_ + 1 | _container_uid_ + 1 |
|
||||
| _from_uid_ + 2 | _container_uid_ + 2 |
|
||||
| _from_uid_ + 3 | _container_uid_ + 3 |
|
||||
|
||||
When **podman create** is called by an unprivileged user (i.e. running rootless),
|
||||
the value _from_uid_ is interpreted as an "intermediate UID". In the rootless
|
||||
case, host UIDs are not mapped directly to container UIDs. Instead the mapping
|
||||
happens over two mapping steps:
|
||||
|
||||
host UID -> intermediate UID -> container UID
|
||||
|
||||
The **\-\-uidmap** option only influences the second mapping step.
|
||||
|
||||
The first mapping step is derived by Podman from the contents of the file
|
||||
_/etc/subuid_ and the UID of the user calling Podman.
|
||||
|
||||
First mapping step:
|
||||
| host UID | intermediate UID |
|
||||
| - | - |
|
||||
| UID for the user starting Podman | 0 |
|
||||
| 1st subordinate UID for the user starting Podman | 1 |
|
||||
| 2nd subordinate UID for the user starting Podman | 2 |
|
||||
| 3rd subordinate UID for the user starting Podman | 3 |
|
||||
| nth subordinate UID for the user starting Podman | n |
|
||||
|
||||
To be able to use intermediate UIDs greater than zero, the user needs to have
|
||||
subordinate UIDs configured in _/etc/subuid_. See **subuid**(5).
|
||||
|
||||
The second mapping step is configured with **\-\-uidmap**.
|
||||
|
||||
If for example _amount_ is **5** the second mapping step would look like:
|
||||
|
||||
| intermediate UID | container UID |
|
||||
| - | - |
|
||||
| _from_uid_ | _container_uid_ |
|
||||
| _from_uid_ + 1 | _container_uid_ + 1 |
|
||||
| _from_uid_ + 2 | _container_uid_ + 2 |
|
||||
| _from_uid_ + 3 | _container_uid_ + 3 |
|
||||
| _from_uid_ + 4 | _container_uid_ + 4 |
|
||||
|
||||
Even if a user does not have any subordinate UIDs in _/etc/subuid_,
|
||||
**\-\-uidmap** could still be used to map the normal UID of the user to a
|
||||
container UID by running `podman create --uidmap $container_uid:0:1 --user $container_uid ...`.
|
||||
|
||||
#### **\-\-ulimit**=*option*
|
||||
|
||||
|
||||
@ -1047,23 +1047,71 @@ Remote connections use local containers.conf for defaults
|
||||
Set the umask inside the container. Defaults to `0022`.
|
||||
Remote connections use local containers.conf for defaults
|
||||
|
||||
#### **\-\-uidmap**=*container_uid*:*host_uid*:*amount*
|
||||
#### **\-\-uidmap**=*container_uid*:*from_uid*:*amount*
|
||||
|
||||
Run the container in a new user namespace using the supplied mapping. This option conflicts
|
||||
with the **\-\-userns** and **\-\-subuidname** flags.
|
||||
This option can be passed several times to map different ranges. If calling **podman run**
|
||||
as an unprivileged user, the user needs to have the right to use the mapping. See **subuid**(5).
|
||||
Run the container in a new user namespace using the supplied mapping. This
|
||||
option conflicts with the **\-\-userns** and **\-\-subuidname** options. This
|
||||
option provides a way to map host UIDs to container UIDs. It can be passed
|
||||
several times to map different ranges.
|
||||
|
||||
The following example maps uids 0-1999 in the container to the uids 30000-31999 on the host: **\-\-uidmap=0:30000:2000**.
|
||||
The _from_uid_ value is based upon the user running the command, either rootful or rootless users.
|
||||
* rootful user: *container_uid*:*host_uid*:*amount*
|
||||
* rootless user: *container_uid*:*intermediate_uid*:*amount*
|
||||
|
||||
**Important note:** The new user namespace mapping based on **\-\-uidmap** is based on the initial mapping made in the _/etc/subuid_ file.
|
||||
Assuming there is a _/etc/subuid_ mapping **username:100000:65536**, then **username** is initially mapped to a namespace starting with
|
||||
uid **100000** for **65536** ids. From here the **\-\-uidmap** mapping to the new namespace starts from **0** again, but is based on the initial mapping.
|
||||
Meaning **username** is initially mapped to uid **100000** which is referenced as **0** in the following **\-\-uidmap** mapping. In terms of the example
|
||||
above: The user **username** is mapped to user **100000** of the initial namespace then the
|
||||
**30000**st id of this namespace (which is uid 130000 in this namespace) is mapped to container namespace user id **0**. (username -> 100000 / 30000 -> 0)
|
||||
When **podman run** is called by a privileged user, the option **\-\-uidmap**
|
||||
works as a direct mapping between host UIDs and container UIDs.
|
||||
|
||||
_Note_: A minimal mapping has to have at least container uid **0** mapped to the parent user namespace.
|
||||
host UID -> container UID
|
||||
|
||||
The _amount_ specifies the number of consecutive UIDs that will be mapped.
|
||||
If for example _amount_ is **4** the mapping would look like:
|
||||
|
||||
| host UID | container UID |
|
||||
| - | - |
|
||||
| _from_uid_ | _container_uid_ |
|
||||
| _from_uid_ + 1 | _container_uid_ + 1 |
|
||||
| _from_uid_ + 2 | _container_uid_ + 2 |
|
||||
| _from_uid_ + 3 | _container_uid_ + 3 |
|
||||
|
||||
When **podman run** is called by an unprivileged user (i.e. running rootless),
|
||||
the value _from_uid_ is interpreted as an "intermediate UID". In the rootless
|
||||
case, host UIDs are not mapped directly to container UIDs. Instead the mapping
|
||||
happens over two mapping steps:
|
||||
|
||||
host UID -> intermediate UID -> container UID
|
||||
|
||||
The **\-\-uidmap** option only influences the second mapping step.
|
||||
|
||||
The first mapping step is derived by Podman from the contents of the file
|
||||
_/etc/subuid_ and the UID of the user calling Podman.
|
||||
|
||||
First mapping step:
|
||||
| host UID | intermediate UID |
|
||||
| - | - |
|
||||
| UID for the user starting Podman | 0 |
|
||||
| 1st subordinate UID for the user starting Podman | 1 |
|
||||
| 2nd subordinate UID for the user starting Podman | 2 |
|
||||
| 3rd subordinate UID for the user starting Podman | 3 |
|
||||
| nth subordinate UID for the user starting Podman | n |
|
||||
|
||||
To be able to use intermediate UIDs greater than zero, the user needs to have
|
||||
subordinate UIDs configured in _/etc/subuid_. See **subuid**(5).
|
||||
|
||||
The second mapping step is configured with **\-\-uidmap**.
|
||||
|
||||
If for example _amount_ is **5** the second mapping step would look like:
|
||||
|
||||
| intermediate UID | container UID |
|
||||
| - | - |
|
||||
| _from_uid_ | _container_uid_ |
|
||||
| _from_uid_ + 1 | _container_uid_ + 1 |
|
||||
| _from_uid_ + 2 | _container_uid_ + 2 |
|
||||
| _from_uid_ + 3 | _container_uid_ + 3 |
|
||||
| _from_uid_ + 4 | _container_uid_ + 4 |
|
||||
|
||||
Even if a user does not have any subordinate UIDs in _/etc/subuid_,
|
||||
**\-\-uidmap** could still be used to map the normal UID of the user to a
|
||||
container UID by running `podman run --uidmap $container_uid:0:1 --user $container_uid ...`.
|
||||
|
||||
#### **\-\-ulimit**=*option*
|
||||
|
||||
|
||||
Reference in New Issue
Block a user