[Xiaobai chat cloud] suggestions on container transformation of small and medium-sized enterprises

Suggestions on container transformation of small and medium-sized enterprises

Enterprises Application of container transformation , There are generally three ways ：

• Mode one ： The monomer is applied as a whole container , The application code and architecture will not be changed .

• Mode two ： Upgrade the application frequently , Or the components with high requirements for elastic expansion are disassembled , Container this part of the component .

• Mode three ： Make a comprehensive microservice architecture transformation of the application , And then container it separately .

For small and medium-sized enterprises , It is the first time to make container transformation , It is suggested to choose mode 1 , The main advantages are ：

• Business 0 modify ： The application architecture and code do not need to be changed .

• Improve deployment and upgrade efficiency ： Applications can be built as container images , Ensure the consistency of the application environment , Improve deployment efficiency .

• Reduce resource costs ：Docker High utilization of system resources . Compared with virtual machine technology , A host with the same configuration , It's often possible to run more applications .

After determining the transformation mode of containerization , Enterprises can start to transform . Take the recent transformation of a small and medium-sized enterprise as an example .

The current situation of the enterprise ： The enterprise currently 2 platform web Server as front end ,mysql database , Software load balancer , No database middleware , Back end EVS Cloud drive .

Enterprise transformation point ：

1、 Load balancing application transformation point ： Choose the right load balancer . Generally, small and medium-sized Web Applications can use ngnix or HAProxy, Large websites or important services can be used LVS, At present, the business scale of the enterprise is small , selection nginx As load balancer ;

2、web Application transformation point ： The application has a long execution request . Add message queue , Decouple long tasks from user requests through message queuing .

3、 Application server application transformation point ： Application instances rely on local storage to persist data . Log suggestions become streams converged into distributed log systems . If you have to use storage , Use a shared file system such as NFS.

4、 Resource and Cluster Planning ： At present, single cluster planning is adopted （ Suppose there are other application projects in cloud resources ）, Show me the intention as follows ：

5、 High availability planning

• Respectively in 2 individual AZ Two sets are deployed in the middle CCE colony ,K8S Master Use local 3 Node high availability deployment .

• application AZ High availability deployment in , adopt ClusterIP Service invocation does not span AZ.

• Application of release LoadBalancer Type of Service Connect to the cluster AZ Fusion ELB Service instance .

• Application passed VIP Access database , The application of automatic database switching is not aware .

• Support more AZ Dynamic container storage , according to pod Where AZ Creating a data volume .

6、 Network planning

By default, applications within the cluster can pass ClusterIP Type services communicate with each other .k8s Built in cluster DNS service , Access between services can be through IP Or domain name access .K8S The interconnection diagram of internal application network is as follows ：

Step1：kube-proxy、core-dns from Master in kube-apiserver subscribe service,POD2 Of Service Creation time ,kube-proxy Refresh this node iptables,core-DNS Update routing data .

Step2：Pod2 Access through domain name Pod4 Of service4, Initiated to core-dns Query request , And get the corresponding ClusterIP（ If you use ClusterIP Direct access ignores this step ）

Step3：Pod2 Send business message , The destination address is obtained ClusterIP. The container network matches the policy according to the destination address VxLAN encapsulation , The package source address is the container VM IP Address , The destination address is the destination container VM IP, And send the message to I layer vSwitch, Then forward to the destination container VM, Container network solution VxLAN After encapsulation , according to ClusterIP Send the business message to service And POD.