traefik是一个使你把微服务暴露出来变的更容易的http反向代理和负载均衡软件。traefik支持K8S、docker swarm、mesos、consul、etcd、zookeeper等基础设施组件，个人认为更适合容器化的微服务，traefik的配置会自动的、动态的配置更新自己。traefik的原理在另一篇讲解，本章直接实战看效果。

场景

    本篇主要模拟的是traefik+docker swarm mode的场景，由traefik自动发现swarm mode下的service

环境

    ps：还是之前文章做实验的swarm集群

下载traefik

      wget 'https://github-production-release-asset-2e65be.s3.amazonaws.com/42408804/b7288f00-a48e-11e8-817e-298aa1a8bae9?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIWNJYAX4CSVEH53A%2F20180903%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20180903T065922Z&X-Amz-Expires=300&X-Amz-Signature=4d4a6a61122a5e0ac8aaae5da30883d555db307c2a9dbe1e300fb1dc2decb0a2&X-Amz-SignedHeaders=host&actor_id=12913767&response-content-disposition=attachment%3B%20filename%3Dtraefik_linux-amd64&response-content-type=application%2Foctet-stream'

    ps：把下载完的traefik_linux-amd64二进制文件重命名成traefik，上传到镜像制作服务器。

镜像制作

    Dockfile

      FROM scratch
COPY ./traefik /
EXPOSE 80
ENTRYPOINT ["/traefik"]

    编译image

      docker build -t traefik .

    上传image

      docker tag traefik 172.31.68.241/library/traefik
docker push 172.31.68.241/library/traefik

部署traefik

    创建网络

      docker network create --driver=overlay traefik-net

        ps：traefik和app要在同一个网络内，否则traefik识别不到app

    部署traefik

      docker service create \
    --name traefik \
    --constraint=node.role==manager \
    --publish 8090:80 --publish 8080:8080 \
    --mount type=bind,source=/var/run/docker.sock,target=/var/run/docker.sock \
    --network traefik-net \
    172.31.68.241/library/traefik \
    --docker \
    --docker.swarmMode \
    --docker.domain=example.org  \
    --docker.watch \
    --logLevel=DEBUG \
    --web

    查看web

      http://172.31.68.241:8080/dashboard/

轮训访问app

      docker service  create --replicas 2 --network traefik-net --label traefik.port=80 --label traefik.frontend.rule=Host:test.example.org --name hello 172.31.68.241/library/friendlyhello

    验证

      curl -H Host:test.example.org http://172.31.68.241:8090

会话粘滞访问app

      docker service  create --replicas 2 --network traefik-net --label traefik.port=80 --label traefik.frontend.rule=Host:test.example.org --label traefik.backend.loadbalancer.sticky=true --name hello 172.31.68.241/library/friendlyhello

    验证

      curl -c cookies.txt -H Host:test.example.org http://172.31.68.241:8090

curl -b cookies.txt -H Host:test.example.org http://172.31.68.241:8090

    查看cookies