buildah bud - Build an image using instructions from Dockerfiles.
buildah bud | build-using-dockerfile [options [...]] [context]
Builds an image using instructions from one or more Dockerfiles and a specified build context directory. The build context directory can be specified as the http or https URL of an archive which will be retrieved and extracted to a temporary location.
--add-host=[]
Add a custom host-to-IP mapping (host:ip)
Add a line to /etc/hosts. The format is hostname:ip. The --add-host option can be set multiple times.
--authfile path
Path of the authentication file. Default is ${XDG_RUNTIME_DIR}/containers/auth.json, which is set using podman login.
If the authorization state is not found there, $HOME/.docker/config.json is checked, which is set using docker login.
--build-arg arg=value
Specifies a build argument and its value, which will be interpolated in instructions read from the Dockerfiles in the same way that environment variables are, but which will not be added to environment variable list in the resulting image's configuration.
--cert-dir path
Use certificates at path (*.crt, *.cert, *.key) to connect to the registry. Default certificates directory is /etc/containers/certs.d.
--cgroup-parent=""
Path to cgroups under which the cgroup for the container will be created. If the path is not absolute, the path is considered to be relative to the cgroups path of the init process. Cgroups will be created if they do not already exist.
--cpu-period=0
Limit the CPU CFS (Completely Fair Scheduler) period
Limit the container's CPU usage. This flag tell the kernel to restrict the container's CPU usage to the period you specify.
--cpu-quota=0
Limit the CPU CFS (Completely Fair Scheduler) quota
Limit the container's CPU usage. By default, containers run with the full CPU resource. This flag tell the kernel to restrict the container's CPU usage to the quota you specify.
--cpu-shares=0
CPU shares (relative weight)
By default, all containers get the same proportion of CPU cycles. This proportion can be modified by changing the container's CPU share weighting relative to the weighting of all other running containers.
To modify the proportion from the default of 1024, use the --cpu-shares flag to set the weighting to 2 or higher.
The proportion will only apply when CPU-intensive processes are running. When tasks in one container are idle, other containers can use the left-over CPU time. The actual amount of CPU time will vary depending on the number of containers running on the system.
For example, consider three containers, one has a cpu-share of 1024 and two others have a cpu-share setting of 512. When processes in all three containers attempt to use 100% of CPU, the first container would receive 50% of the total CPU time. If you add a fourth container with a cpu-share of 1024, the first container only gets 33% of the CPU. The remaining containers receive 16.5%, 16.5% and 33% of the CPU.
On a multi-core system, the shares of CPU time are distributed over all CPU cores. Even if a container is limited to less than 100% of CPU time, it can use 100% of each individual CPU core.
For example, consider a system with more than three cores. If you start one container {C0} with -c=512 running one process, and another container {C1} with -c=1024 running two processes, this can result in the following division of CPU shares:
PID container CPU CPU share
100 {C0} 0 100% of CPU0
101 {C1} 1 100% of CPU1
102 {C1} 2 100% of CPU2
--cpuset-cpus=""
CPUs in which to allow execution (0-3, 0,1)
--cpuset-mems=""
Memory nodes (MEMs) in which to allow execution (0-3, 0,1). Only effective on NUMA systems.
If you have four memory nodes on your system (0-3), use --cpuset-mems=0,1
then processes in your container will only use memory from the first
two memory nodes.
--creds creds
The [username[:password]] to use to authenticate with the registry if required. If one or both values are not supplied, a command line prompt will appear and the value can be entered. The password is entered without echo.
-f, --file Dockerfile
Specifies a Dockerfile which contains instructions for building the image, either a local file or an http or https URL. If more than one Dockerfile is specified, FROM instructions will only be accepted from the first specified file.
If a build context is not specified, and at least one Dockerfile is a local file, the directory in which it resides will be used as the build context.
--format
Control the format for the built image's manifest and configuration data. Recognized formats include oci (OCI image-spec v1.0, the default) and docker (version 2, using schema format 2 for the manifest).
-m, --memory=""
Memory limit (format: [], where unit = b, k, m or g)
Allows you to constrain the memory available to a container. If the host supports swap memory, then the -m memory setting can be larger than physical RAM. If a limit of 0 is specified (not using -m), the container's memory is not limited. The actual limit may be rounded up to a multiple of the operating system's page size (the value would be very large, that's millions of trillions).
--memory-swap="LIMIT"
A limit value equal to memory plus swap. Must be used with the -m
(--memory) flag. The swap LIMIT should always be larger than -m
(--memory) value. By default, the swap LIMIT will be set to double
the value of --memory.
The format of LIMIT is <number>[<unit>]. Unit can be b (bytes),
k (kilobytes), m (megabytes), or g (gigabytes). If you don't specify a
unit, b is used. Set LIMIT to -1 to enable unlimited swap.
--pull
Pull the image if it is not present. If this flag is disabled (with --pull=false) and the image is not present, the image will not be pulled. Defaults to true.
--pull-always
Pull the image even if a version of the image is already present.
-q, --quiet
Suppress output messages which indicate which instruction is being processed, and of progress when pulling images from a registry, and when writing the output image.
--runtime path
The path to an alternate OCI-compatible runtime, which will be used to run commands specified by the RUN instruction.
--runtime-flag flag
Adds global flags for the container rutime. To list the supported flags, please
consult the manpages of the selected container runtime (runc is the default
runtime, the manpage to consult is runc(8)).
Note: Do not pass the leading -- to the flag. To pass the runc flag --log-format json
to buildah bud, the option given would be --runtime-flag log-format=json.
--security-opt=[]
Security Options
"label=user:USER" : Set the label user for the container "label=role:ROLE" : Set the label role for the container "label=type:TYPE" : Set the label type for the container "label=level:LEVEL" : Set the label level for the container "label=disable" : Turn off label confinement for the container "no-new-privileges" : Not supported
"seccomp=unconfined" : Turn off seccomp confinement for the container "seccomp=profile.json : White listed syscalls seccomp Json file to be used as a seccomp filter
"apparmor=unconfined" : Turn off apparmor confinement for the container "apparmor=your-profile" : Set the apparmor confinement profile for the container
--signature-policy signaturepolicy
Pathname of a signature policy file to use. It is not recommended that this option be used, as the default behavior of using the system-wide default policy (frequently /etc/containers/policy.json) is most often preferred.
-t, --tag imageName
Specifies the name which will be assigned to the resulting image if the build process completes successfully.
--tls-verify bool-value
Require HTTPS and verify certificates when talking to container registries (defaults to true).
--ulimit=[]
Ulimit options
buildah bud .
buildah bud -f Dockerfile.simple .
buildah bud -f Dockerfile.simple -f Dockerfile.notsosimple
buildah bud -t imageName .
buildah bud --tls-verify=true -t imageName -f Dockerfile.simple
buildah bud --tls-verify=false -t imageName .
buildah bud --runtime-flag log-format=json .
buildah bud --runtime-flag debug .
buildah bud --authfile /tmp/auths/myauths.json --cert-dir ~/auth --tls-verify=true --creds=username:password -t imageName -f Dockerfile.simple
buildah bud --memory 40m --cpu-period 10000 --cpu-quota 50000 --ulimit nofile=1024:1028 -t imageName .
buildah bud --security-opt label=level:s0:c100,c200 --cgroup-parent /path/to/cgroup/parent -t imageName .
buildah(1), podman-login(1), docker-login(1)