问题描述
我有一个由三个节点组成的群:
I have a swarm composed of three nodes:
$ sudo docker node ls
ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS
i12s3zxsn4vu1c98bv3i5idr8 node03 Ready Active
i2ckxvsju4tmommxim3dbfq7l node02 Ready Active
wak4isl46dn7pbo39drrhphju * node01 Ready Active Leader
然后，我在该群集上运行1个nginx副本，并将其端口映射到8080:
Then I run 1 replica of nginx on that swarm and map his port to 8080:
$ sudo docker service create --replicas 1 --publish 8080:80 --name nginx nginx
$ sudo docker service ls
ID NAME MODE REPLICAS IMAGE PORTS
neahnb9mvi1i nginx replicated 1/1 nginx:latest *:8080->80/tcp
从那里，我可以通过 http://node01:8080
接下来，我将nginx实例缩放为6:
Next, I scale nginx instances to 6:
$ sudo docker service scale nginx=6
$ sudo docker service ls
ID NAME MODE REPLICAS IMAGE PORTS
neahnb9mvi1i nginx replicated 6/6 nginx:latest *:8080->80/tcp
从那里，我仍然可以通过 http://node01:8080 到达nginx.
From there, i'm still able to reach nginx on http://node01:8080.
但是，如果docker swarm将多个节点作为唯一主机公开，那么在我的所有nginx服务都映射到相同的8080端口时，他如何在扩展操作期间管理端口?在内部由群集完成并返回8080答案的所有服务实例之间是否存在循环负载平衡?
However, if docker swarm expose several node as a unique host, how does he manage the port during such a scaling operation as all my nginx services are mapped on the same 8080 port? Is there a round robin load balancing between all services instances done by swarm internally and returning the answer on 8080?
推荐答案
我相信对主机的请求将以循环类型分配的方式分配.
I believe the requests to the hosts get assigned in a round-robin type assignment.
找到了关于此的便捷文章 http://blog.scottlogic.com/2016/08/30/docker-1-12-swarm-mode-round-robin.html .检出标题为" INGRESS AND ROUND ROBIN LOAD BALANCING "的零件.
Found this handy article about it http://blog.scottlogic.com/2016/08/30/docker-1-12-swarm-mode-round-robin.html . Checkout the part titled 'INGRESS AND ROUND ROBIN LOAD BALANCING'.
这篇关于Docker群在端口映射上的扩展行为的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！