# Linkerd2 Linkerd2 （曾命名为 [Conduit](https://conduit.io)） 是 Buoyant 公司推出的下一代轻量级服务网格框架，开源在 。与 linkerd 不同的是，它专用于 Kubernetes 集群中，并且比 linkerd 更轻量级（基于 Rust 和 Go，没有了 JVM 等大内存的开销），可以以 sidecar 的方式把代理服务跟实际服务的 Pod 运行在一起（这点跟 Istio 类似）。Linkerd2 的主要特性包括： * 轻量级，速度快，每个代理容器仅占用 10mb RSS，并且额外延迟只有亚毫妙级 * 安全，基于 Rust，默认开启 TLS * 端到端可视化 * 增强 Kubernetes 的可靠性、可视性以及安全性 ## 部署 ```bash $ linkerd install | kubectl apply -f - namespace/linkerd configured serviceaccount/linkerd-controller configured clusterrole.rbac.authorization.k8s.io/linkerd-linkerd-controller configured clusterrolebinding.rbac.authorization.k8s.io/linkerd-linkerd-controller configured serviceaccount/linkerd-prometheus configured clusterrole.rbac.authorization.k8s.io/linkerd-linkerd-prometheus configured clusterrolebinding.rbac.authorization.k8s.io/linkerd-linkerd-prometheus configured service/api configured service/proxy-api configured deployment.extensions/controller configured service/web configured deployment.extensions/web configured service/prometheus configured deployment.extensions/prometheus configured configmap/prometheus-config configured service/grafana configured deployment.extensions/grafana configured configmap/grafana-config configured $ kubectl -n linkerd get svc NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE api ClusterIP 10.0.173.27 8085/TCP 163m grafana ClusterIP 10.0.49.44 3000/TCP 163m prometheus ClusterIP 10.0.205.82 9090/TCP 163m proxy-api ClusterIP 10.0.170.201 8086/TCP 163m web ClusterIP 10.0.88.136 8084/TCP,9994/TCP 163m $ kubectl -n linkerd get pod NAME READY STATUS RESTARTS AGE controller-67489d768d-75wjz 5/5 Running 0 163m grafana-5df745d8b8-pv6tf 2/2 Running 0 163m prometheus-d96f9bf89-2s6jg 2/2 Running 0 163m web-5cd59f97b6-wf8nk 2/2 Running 0 57s ``` ## Dashboard ```bash $ linkerd dashboard Linkerd dashboard available at: http://127.0.0.1:37737/api/v1/namespaces/linkerd/services/web:http/proxy/ Grafana dashboard available at: http://127.0.0.1:37737/api/v1/namespaces/linkerd/services/grafana:http/proxy/ Opening Linkerd dashboard in the default browser ``` ![](/files/BDYqb9oKOl0UzWnDdyLW) ## 示例应用 ```bash curl https://run.linkerd.io/emojivoto.yml \ | linkerd inject - \ | kubectl apply -f - ``` 查看服务的网络流量统计情况： ```bash linkerd -n emojivoto stat deployment NAME MESHED SUCCESS RPS LATENCY_P50 LATENCY_P95 LATENCY_P99 TLS emoji 1/1 100.00% 8.1rps 1ms 1ms 1ms 0% vote-bot 1/1 - - - - - - voting 1/1 87.88% 1.1rps 1ms 1ms 1ms 0% web 1/1 93.65% 2.1rps 1ms 9ms 88ms 0% ``` 跟踪服务的网络流量 ```bash $ linkerd -n emojivoto tap deploy voting req id=0:809 src=10.244.6.239:57202 dst=10.244.1.237:8080 :method=POST :authority=voting-svc.emojivoto:8080 :path=/emojivoto.v1.VotingService/VoteDoughnut rsp id=0:809 src=10.244.6.239:57202 dst=10.244.1.237:8080 :status=200 latency=478µs end id=0:809 src=10.244.6.239:57202 dst=10.244.1.237:8080 grpc-status=OK duration=7µs response-length=5B req id=0:810 src=10.244.6.239:57202 dst=10.244.1.237:8080 :method=POST :authority=voting-svc.emojivoto:8080 :path=/emojivoto.v1.VotingService/VoteDoughnut rsp id=0:810 src=10.244.6.239:57202 dst=10.244.1.237:8080 :status=200 latency=419µs end id=0:810 src=10.244.6.239:57202 dst=10.244.1.237:8080 grpc-status=OK duration=8µs response-length=5B ``` ## 参考文档 * [A SERVICE MESH FOR KUBERNETES](https://buoyant.io/2016/10/04/a-service-mesh-for-kubernetes-part-i-top-line-service-metrics/) * [Service Mesh Pattern](http://philcalcado.com/2017/08/03/pattern_service_mesh.html) * --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://kubernetes.feisky.xyz/apps/index/linkerd2.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.