por The command Docker Update refers to the tool that allows you to update the resources assigned to a container and its configurations respective, that is, this tool is responsible for dynamically updating the container configuration.
Additionally, Docker Update is used to prevent containers from spending too much of your resources host Docker. So this single command serves the purpose of establishing the limits on one or more containers. It should be noted that if the user wants to specify more than one container, they need to provide a space-separated list of the names (also called IDs) of the selected containers.
Among the functions of the Docker Update command is update the CPU elements of a container as well as a container with shared CPU and memory resources. Similarly, this command allows you to update the memorial restrictions kernel or heart of a container, as well as carrying out the update process regarding the restart policy of a container, among other functions.
Docker Update Options
Among the Doker Update options are:
–cpu-quota: is an option of the Docker Update command that is responsible for limiting the CFS CPU quota.–cpu-period: is the option that is responsible for limiting the CFS CPU period.–cpu-rt-period– This Docker Update option serves the purpose of limiting the real-time period of the CPU in microseconds.–kernel-memory: refers to the kernel memory limit or kernel.–memory: also known by its abbreviation -m. Refers to the option that sets the memory limit.–memory-swap: is the option related to the swap limit equal to memory, in addition to swap: «-1» which enables unlimited type swap.–memory-reservation– is an option of the Docker Update command that takes care of memory soft limit.–restart– Refers to the Docker Update option that works as a restart policy to apply when a container exits.
Docker Update Limitations
Within the limitations of the Docker Update command, it must be taken into account that Dockers cannot be completely modifiedbut generally only some elements can be changed such as the resource limitation, this being the case of the CPU and memory.
Besides, It is also not possible to make modifications to the volumes, ports and environment variables that a user assigned it to a certain container. Although this usually should not represent a problem, because in those cases you only need to destroy the docker and create a new one. If it happens that the user loses their data or there are system failures, it means that one of the internal processes was not running correctly.
What is the next step?
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