Understanding Modern Application Architecture - Part 1
This is part 1 of a series. Here are the other parts: Understanding Modern Application Architecture - Part 2 Understanding Modern Application Architecture - Part 3 Over the past decade, there has been a change taking place in how applications are built. As applications become more expansive in capabilities and more critical to how a business operates, (or in many cases, the application is the business itself) a new style of architecture has allowed for increased scalability, portability, resiliency, and agility. To support the goals of a modern application, the surrounding infrastructure has had to evolve as well. Platforms like Kubernetes have played a big role in unlocking the potential of modern applications and is a new paradigm in itself for how infrastructure is managed and served. To help our community transition the skillset they've built to deal with monolithic applications, we've put together a series of videos to drive home concepts around modern applications. This article highlights some of the details found within the video series. In these first three videos, we breakdown the definition of a Modern Application. One might think that by name only, a modern application is simply an application that is current. But we're actually speaking in comparison to a monolithic application. Monolithic applications are made up of a single, or a just few pieces. They are rigid in how they are deployed and fragile in their dependencies. Modern applications will instead incorporate microservices. Where a monolithic application might have all functions built into one broad encompassing service, microservices will break down the service into smaller functions that can be worked on separately. A modern application will also incorporate 4 main pillars. Scalability ensures that the application can handle the needs of a growing user base, both for surges as well as long term growth. Portability ensures that the application can be transportable from its underlying environment while still maintaining all of its functionality and management plane capabilities. Resiliency ensures that failures within the system go unnoticed or pose minimal disruption to users of the application. Agility ensures that the application can accommodate for rapid changes whether that be to code or to infrastructure. There are also 6 design principles of a modern application. Being agnostic will allow the application to have freedom to run on any platform. Leveraging open source software where it makes sense can often allow you to move quickly with an application but later be able to adopt commercial versions of that software when full support is needed. Defining by code allows for more uniformity of configuration and move away rigid interfaces that require specialized knowledge. Automated CI/CD processes ensures the quick integration and deployment of code so that improvements are constantly happening while any failures are minimized and contained. Secure development ensures that application security is integrated into the development process and code is tested thoroughly before being deployed into production. Distributed Storage and Infrastructure ensures that applications are not bound by any physical limitations and components can be located where they make the most sense. These videos should help set the foundation for what a modern application is. The next videos in the series will start to define the fundamental technical components for the platforms that bring together a modern application. Continued in Part 2Understanding Modern Application Architecture - Part 3
In this last article of the series discussing Modern Application Architecture, we will be discussion manageability with respect to the traffic. As the traffic patterns grow and look quite different from monolithic applications, different approaches need to take place in order to maintain the stability of the application. Understanding Modern Application Architecture - Part 1 Understanding Modern Application Architecture - Part 2 In this next video, we discuss Service Mesh. As modern applications expand and their communications change to microservice to microservice, a service mesh can be introduced to provide control, security and visibility to that traffic. Since individual microservices can be written by different individuals or groups, the service mesh can be the intermediary that allows them to understand what is happening when one piece of code needs to speak to another piece of code. At the same time, trust and verification can happen between the microservices to ensure they are talking to what they should be talking to. In this next video we discuss Sidecar Proxies. As mentioned in the Service Mesh video, the sidecar proxy is a key piece of the mesh implementation. It is responsible for functions such as TLS termination, mutual TLS and authentication. It can also be used for tracing and other observability. This means these functions don't have to be performed by the microservice itself. In this final video, we review NGINX as a Production Grade Kubernetes Solution. While Modern Applications will adopt Open Source Solutions where possible, these applications can be mission critical ones that require the highest level of service. As mentioned in the previous videos in this series, there are a number of important pieces of a Kubernetes cluster that can be augmented, or replaced by enhanced services. NGINX can actually perform as an enhanced Ingress Controller, giving a high level of control as well as performance for inbound traffic to the cluster. NGINX with App Protect can also provide finer grain controlled web application security for the inbound web based components of the application. And finally, NGINX Service Mesh can help with the microservice to microservice control, security and visibility, offloading that function from the microservice itself. We hope that this video series has helped shed some light for those who are curious about modern application architecture. As you have questions, don't hesistate to ask in our Technical Forums!
Understanding Modern Application Architecture - Part 2
To help our Community transfer their skills to handle Modern Applications, we've released a video series to explain the major points. This article is part 2 and here are the other parts: Understanding Modern Application Architecture - Part 1 Understanding Modern Application Architecture - Part 3 This next set of videos discuss the platforms and components that make up modern applications. In this video, we review containers. These have become a key building block of microservices. They help achieve the application portability by neatly packaging up everything needing to bring up an application within a container runtime such as Docker. One great example of a container is the f5-demo-httpd container. This small lightweight container can be downloaded quickly to run a web server. It's incorporated into a lot of F5 demo environments because it is lightweight and can be customized by simply forking the repository and making your own changes. In this next video, we talk about Kubernetes (or k8s for short). While there are container runtimes like Docker that can work individually on a server, the Kubernetes project has brought the concept into a form that can be scaled out. Worker nodes, where containers are run on, can be brought together into clusters. Commands can be issued to a Master Node via YAML files and have affect across the cluster. Containers can be scheduled efficiently across a cluster which is managed as one. In this next video, we break down the Kubernetes API. The Kubernetes API is the main interface to a k8s cluster. While there are GUI solutions that can be added to a k8s cluster, they are still interfacing with the API so it is important to understand what the API is capable of and what it is doing with the cluster. The main way to issue commands to the API is through YAML files and the kubectl command. From there, the API server will interact with the other parts of the cluster to perform operations. In this next video, we discuss Securing a Kubernetes cluster. There are a number of attack vectors that need to be understood and so we review them along with some of the actions that can be taken in order to increase the security for them. In this next video, we go over Ingress Controller. An Ingres Controller is one of the main ways that traffic is brought from outside of the cluster, into a pod. This role is of particular interest to F5 customers as they can use NGINX, NGINX+ or BIG-IP to play this strategic role within a Kubernetes cluster. In this next video, we talk about Microservices. As applications are decomposed from monolithic applications to modern applications, they are broken up into microservices that carry out individual functions of an application. The microservices then communicate with each other in order to deliver the overall application. It's important to then understand this service to service communication so that you can design application services around them such as load balancing, routing, visibility and security. We hope that you've enjoyed this video series so far. In the next article, we'll be reviewing the components that aid in the management of a Kubernetes platform.Understanding Modern Application Architecture - Part 3
CIS and Kubernetes - Part 2: Install F5 Container ingress services
In our previous article, we have setup Kubernetes and calico with our BIG-IPs. Now we will setup F5 Container Ingress Services (F5 CIS) and deploy an ingress service. Note: in this deployment, we will setup F5 CIS in the namespace kube-system BIG-IPs Setup Setup our Kubernetes partition Before deploying F5 Container Ingress Services, we need to setup our BIG-IPs: Setup a partition that CIS will use. Install AS3 On EACH BIG-IP, you need to do the following: In the GUI, go to System > User > Partitions List and click on the Create button Create a partition called "kubernetes" and click Finished Next we need to download the AS3 extension and install it on each BIG-IP. Install AS3 Go to GitHub . Select the release with the "latest" tag and download the rpm. Once you have the rpm, go to iApps > Package Management LX and click the Import button (you need to run BIG-IP v12.1 or later) on EACH BIG-IP Chose your rpm and click Upload. Once the rpm has been uploaded and loaded, you should see this: Our BIG-IPs are setup properly now. Next, we will deploy F5 CIS CIS Deployment Connect to your Kubernetes cluster. We will need to setup the following: Create a Kubernetes secret to store our BIG-IPs credentials Setup a service account for CIS and setup RBAC Setup our CIS configuration. We will need 1xCIS per BIG-IP (even when BIG-IP is setup as a cluster - we don't recommend automatic sync between BIG-IPs) Deploy one CIS per BIG-IP Store our BIG-IP credentials in a kubernetes secret To store your credentials (login/password) in a kubernetes secret, you can run the following command (https://clouddocs.f5.com/containers/v2/kubernetes/kctlr-secrets.html#secret-bigip-login): kubectl create secret generic bigip-login --namespace kube-system --from-literal=username=<your_login> --from-literal=password=<your_password> In my setup, my credentials are the following: Login: admin Password: D3f4ult123 So we'll run the following command: kubectl create secret generic bigip-login --namespace kube-system --from-literal=username=admin --from-literal=password=D3f4ult123 ubuntu@ip-10-1-1-4:~$ kubectl create secret generic bigip-login --namespace kube-system --from-literal=username=admin --from-literal=password=D3f4ult123 secret/bigip-login created Create a Service Account /RBAC for CIS Now we need to create our service account (https://clouddocs.f5.com/containers/v2/kubernetes/kctlr-app-install.html#set-up-rbac-authentication): Run the following command: : kubectl create serviceaccount bigip-ctlr -n kube-system ubuntu@ip-10-1-1-4:~$ kubectl create serviceaccount bigip-ctlr -n kube-system serviceaccount/bigip-ctlr created Use your favorite editor to create this file: f5-k8s-sample-rbac.yaml: # for use in k8s clusters only # for OpenShift, use the OpenShift-specific examples kind: ClusterRole apiVersion: rbac.authorization.k8s.io/v1 metadata: name: bigip-ctlr-clusterrole rules: - apiGroups: ["", "extensions"] resources: ["nodes", "services", "endpoints", "namespaces", "ingresses", "pods"] verbs: ["get", "list", "watch"] - apiGroups: ["", "extensions"] resources: ["configmaps", "events", "ingresses/status"] verbs: ["get", "list", "watch", "update", "create", "patch"] - apiGroups: ["", "extensions"] resources: ["secrets"] resourceNames: ["<secret-containing-bigip-login>"] verbs: ["get", "list", "watch"] --- kind: ClusterRoleBinding apiVersion: rbac.authorization.k8s.io/v1 metadata: name: bigip-ctlr-clusterrole-binding namespace: kube-system roleRef: apiGroup: rbac.authorization.k8s.io kind: ClusterRole name: bigip-ctlr-clusterrole subjects: - apiGroup: "" kind: ServiceAccount name: bigip-ctlr namespace: kube-system Deploy this config by running the following command: kubectl apply -f f5-k8s-sample-rbac.yaml ubuntu@ip-10-1-1-4:~$ kubectl apply -f f5-k8s-sample-rbac.yaml clusterrole.rbac.authorization.k8s.io/bigip-ctlr-clusterrole created clusterrolebinding.rbac.authorization.k8s.io/bigip-ctlr-clusterrole-binding created Next step is to setup our CIS deployment files Create our CIS deployment configurations Use your favorite editor to create the following files: setup_cis_bigip1.yaml: apiVersion: apps/v1 kind: Deployment metadata: name: k8s-bigip1-ctlr-deployment namespace: kube-system spec: selector: matchLabels: app: k8s-bigip1-ctlr # DO NOT INCREASE REPLICA COUNT replicas: 1 template: metadata: labels: app: k8s-bigip1-ctlr spec: # Name of the Service Account bound to a Cluster Role with the required # permissions serviceAccountName: bigip-ctlr containers: - name: k8s-bigip-ctlr image: "f5networks/k8s-bigip-ctlr" env: - name: BIGIP_USERNAME valueFrom: secretKeyRef: # Replace with the name of the Secret containing your login # credentials name: bigip-login key: username - name: BIGIP_PASSWORD valueFrom: secretKeyRef: # Replace with the name of the Secret containing your login # credentials name: bigip-login key: password command: ["/app/bin/k8s-bigip-ctlr"] args: [ # See the k8s-bigip-ctlr documentation for information about # all config options # https://clouddocs.f5.com/products/connectors/k8s-bigip-ctlr/latest "--bigip-username=$(BIGIP_USERNAME)", "--bigip-password=$(BIGIP_PASSWORD)", "--bigip-url=10.1.20.11", "--bigip-partition=kubernetes", "--insecure=true", "--pool-member-type=cluster", "--agent=as3" ] imagePullSecrets: # Secret that gives access to a private docker registry - name: f5-docker-images # Secret containing the BIG-IP system login credentials - name: bigip-login setup_cis_bigip2.yaml: apiVersion: apps/v1 kind: Deployment metadata: name: k8s-bigip2-ctlr-deployment namespace: kube-system spec: selector: matchLabels: app: k8s-bigip2-ctlr # DO NOT INCREASE REPLICA COUNT replicas: 1 template: metadata: labels: app: k8s-bigip2-ctlr spec: # Name of the Service Account bound to a Cluster Role with the required # permissions serviceAccountName: bigip-ctlr containers: - name: k8s-bigip-ctlr image: "f5networks/k8s-bigip-ctlr" env: - name: BIGIP_USERNAME valueFrom: secretKeyRef: # Replace with the name of the Secret containing your login # credentials name: bigip-login key: username - name: BIGIP_PASSWORD valueFrom: secretKeyRef: # Replace with the name of the Secret containing your login # credentials name: bigip-login key: password command: ["/app/bin/k8s-bigip-ctlr"] args: [ # See the k8s-bigip-ctlr documentation for information about # all config options # https://clouddocs.f5.com/products/connectors/k8s-bigip-ctlr/latest "--bigip-username=$(BIGIP_USERNAME)", "--bigip-password=$(BIGIP_PASSWORD)", "--bigip-url=10.1.20.12", "--bigip-partition=kubernetes", "--insecure=true", "--pool-member-type=cluster", "--agent=as3" ] imagePullSecrets: # Secret that gives access to a private docker registry - name: f5-docker-images # Secret containing the BIG-IP system login credentials - name: bigip-login To deploy our CIS, run the following commands: kubectl apply -f setup_cis_bigip1.yaml kubectl apply -f setup_cis_bigip2.yaml You can make sure that they got deployed successfully: kubectl get pods -n kube-system You can review if it launched successfully with the commands: kubectl logs <pod_name> -n kube system ubuntu@ip-10-1-1-4:~$ kubectl logs k8s-bigip2-ctlr-deployment-6f674c8d58-bbzqv -n kube-system 2020/01/03 12:04:06 [INFO] Starting: Version: 1.12.0, BuildInfo: n2050-623590021 2020/01/03 12:04:06 [INFO] ConfigWriter started: 0xc0002bb950 2020/01/03 12:04:06 [INFO] Started config driver sub-process at pid: 14 2020/01/03 12:04:07 [INFO] NodePoller (0xc000b7c090) registering new listener: 0x11bfea0 2020/01/03 12:04:07 [INFO] NodePoller started: (0xc000b7c090) 2020/01/03 12:04:07 [INFO] Watching Ingress resources. 2020/01/03 12:04:07 [INFO] Watching ConfigMap resources. 2020/01/03 12:04:07 [INFO] Handling ConfigMap resource events. 2020/01/03 12:04:07 [INFO] Handling Ingress resource events. 2020/01/03 12:04:07 [INFO] Registered BigIP Metrics 2020/01/03 12:04:07 [INFO] [2020-01-03 12:04:07,663 __main__ INFO] entering inotify loop to watch /tmp/k8s-bigip-ctlr.config563475778/config.json 2020/01/03 12:04:08 [INFO] Successfully Sent the FDB Records You may also check your BIG-IPs configuration: if CIS has been able to connect successfully, it will have created *another* partition called "kubernetes_AS3".This is explained here: https://clouddocs.f5.com/containers/v2/kubernetes/kctlr-use-as3-backend.html CIS will create partitionkubernetes_AS3to store LTM objects such as pools, and virtual servers. FDB, and Static ARP entries are stored inkubernetes. These partitions should not be managed manually. Application Deployment In this section, we will do the following: Deploy an application with 2 replicas (ie 2 instances of our app) Setup an ingress service to connect to your application Deploy our application and service Create the following service and deployment configuration files: f5-hello-world-app-http-deployment.yaml apiVersion: apps/v1 kind: Deployment metadata: name: f5-hello-world namespace: default spec: replicas: 2 selector: matchLabels: app: f5-hello-world template: metadata: labels: app: f5-hello-world spec: containers: - env: - name: service_name value: f5-hello-world image: f5devcentral/f5-hello-world:latest imagePullPolicy: Always name: f5-hello-world ports: - containerPort: 8080 protocol: TCP f5-hello-world-app-http-service.yaml apiVersion: v1 kind: Service metadata: name: f5-hello-world namespace: default labels: app: f5-hello-world spec: ports: - name: f5-hello-world port: 8080 protocol: TCP targetPort: 8080 type: NodePort selector: app: f5-hello-world Apply your deployment and service: kubectl apply -f f5-hello-world-app-http-deployment.yaml kubectl apply -f f5-hello-world-app-http-service.yaml ubuntu@ip-10-1-1-4:~$ kubectl apply -f f5-hello-world-app-http-deployment.yaml deployment.apps/f5-hello-world created ubuntu@ip-10-1-1-4:~$ kubectl apply -f f5-hello-world-app-http-service.yaml service/f5-hello-world created You can review your deployment and service with kubectl get : ubuntu@ip-10-1-1-4:~$ kubectl get pods NAMEREADYSTATUSRESTARTSAGE f5-hello-world-847698f5c6-59mmn1/1Running02m3s f5-hello-world-847698f5c6-pcz9v1/1Running02m3s ubuntu@ip-10-1-1-4:~$ kubectl get svc NAMETYPECLUSTER-IPEXTERNAL-IPPORT(S)AGE f5-hello-worldNodePort10.97.83.208<none>8080:31380/TCP2m kubernetesClusterIP10.96.0.1<none>443/TCP63d Define our ingress service CIS ingress annotations can be reviewed here: https://clouddocs.f5.com/products/connectors/k8s-bigip-ctlr/v1.11/#ingress-resources Create the following file: f5-as3-ingress.yaml: apiVersion: extensions/v1beta1 kind: Ingress metadata: name: singleingress1 namespace: default annotations: # See the k8s-bigip-ctlr documentation for information about # all Ingress Annotations # https://clouddocs.f5.com/products/connectors/k8s-bigip-ctlr/latest/#supported-ingress-annotations virtual-server.f5.com/ip: "10.1.10.80" virtual-server.f5.com/http-port: "443" virtual-server.f5.com/partition: "kubernetes_AS3" virtual-server.f5.com/health: '[{"path": "/", "send": "HTTP GET /", "interval": 5, "timeout": 10}]' spec: backend: # The name of the Service you want to expose to external traffic serviceName: f5-hello-world servicePort: 8080 you can review the BIG-IP configuration by going into the kubernetes_AS3 partition Summary In this article we saw how to deploy CIS with AS3 to handle ingress services. CIS has more capabilities than ingress that you may review here: https://clouddocs.f5.com/containers/v2/kubernetes/ (configmap, routes, …) ---- Relevant links to this article: https://www.f5.com/products/automation-and-orchestration/container-ingress-services https://clouddocs.f5.com/containers/v2/kubernetes/kctlr-use-as3-backend.html https://clouddocs.f5.com/containers/v2/kubernetes/kctlr-k8s-as3.html https://clouddocs.f5.com/containers/v2/kubernetes/kctlr-app-install.html
