Research And Design Of Multi-tenant Model Of Private Container Cloud Platform Based On Kubernetes

With the development of container virtualization technology,container orchestration technology represented by Kubernetes is leading the further construction of enterprise private container cloud platforms.In order to ensure security,the container cloud platform needs to focus on isolation in a multi-tenant environment.At present,Kubernetes can support isolation requirements in basic scenarios through native functions,but it is still slightly insufficient in support of multi-tenant security and cannot provide A complete multi-tenant solution in terms of user authentication,authorization and resource isolation.In order to solve the above problems,this thesis proposes a multi-tenant model covering multi-tenancy access control and resource isolation schemes based on the in-depth analysis of the current Kubernetes multi-tenancy capabilities.Firstly,regarding the problem that roles cannot be automatically assigned through RBAC model in the Kubernetes cluster and access control granularity is low,a multi-tenancy access control model based on attributes and roles(MT-ARBAC)is proposed.RBAC is optimized by introducing attribute set and access structure,combined with ciphertext strategy attribute-based algorithm(CP-ABE).In addition,in order to refine the access rights,a four-tier role model for cluster administrators,tenant administrators,project administrators,and ordinary developers is also designed.Secondly,to solve the problem that Kubernetes cannot provide unified authentication for external users of the cluster,the thesis proposes a kind of the multi-tenancy authentication scheme based on keycloak authentication service and Open ID Connect protocol,to form a complete multitenancy access control scheme with the MT-ARBAC model,and realizes unified authentication and authorization in a multi-tenancy environment.Thirdly,for the shortcomings that docker container engine of kubernetes shared the kernel,a multi-tenancy model of computing resource isolation solution is proposed based on further analysis of the secure container solution and CRI container runtime.Containerd is used as the CRI implementation of Kubernetes,while the underlying container operation solution is designed as combining the kata secure container with the run C.This method separates trusted resources from untrusted resources to ensure the isolation of container operation performance under normal conditions from virtual machines running under untrusted containers,and enhances the security of container operation.Fourthly,regarding of the disadvantages of the default flannel network solution of the kubernetes cluster,based on the research of the CNI network plug-in,a network resource isolation solution of the multi-tenancy model is proposed.Using the Calico network plugin and the Network Policy of kubernetes realizes the isolation of network resources in the multi-tenancy model.Finally,the cluster is deployed based on the multi-tenancy model designed in this thesis,and the function test of the access control and resource isolation part and the network performance test of the cluster are performed.The experimental results show that the Kubernetes multi-tenancy model solution proposed in this thesis meets the multi-tenancy isolation ability required in the design goal and it can achieve a certain degree of security and isolation in terms of multi-tenancy access control,computing resources and network resources.