k8s mount propagation简介

volume的MountPropagation有如下三种

None
HostToContainer
Bidirectional

linux的mount propagation mountflags有如下四种mountflags

MS_SHARED
MS_PRIVATE
MS_SLAVE
MS_UNBINDABLE
对应的mount命令分别为
mount --make-shared mountpoint
mount --make-slave mountpoint
mount --make-private mountpoint
mount --make-unbindable mountpoint
如果是递归的话,则分别为
mount --make-rshared mountpoint
mount --make-rslave mountpoint
mount --make-rprivate mountpoint
mount --make-runbindable mountpoint

简单总结

None通过MS_PRIVATE实现
HostToContainer通过MS_PRIVATE实现
Bidirectional通过MS_SHARED实现