docker-It's possible that too few managers are online. Make sure more than half of the managers are

問題：docker ---- It's possible that too few managers are online. Make sure more than half of the managers are online.  

背景：docker測試集羣，爲3臺虛擬機，鏡像所有拷貝自其它docker 虛擬機。 因爲原先安裝過swarm，先通過拷貝重啓後在執行 dowker swarm XX  時報錯。

 

解決：

 

1.每臺先強制init ：

　　docker swarm init --force-new-cluster     （此時執行 docker node ls --將node信息刪除，緣由是這些node所有來自我拷貝的鏡像中老舊的信息。）

2.而後此時選取 swarm worker節點加入到其中一臺時：docker swarm join --token **** 

　　報錯Error response from daemon: This node is already part of a swarm. Use "docker swarm leave" to leave this swarm and join another one.

3.根據提示須要 docker swarm leave ，而後報錯：

　　Error response from daemon: You are attempting to leave the swarm on a node that is participating as a manager. Removing the last manager erases all current state of the swarm. Use `--force` to ignore this message.

4.根據提示：加上--force ： docker swarm leave --force   而後再從新join便可

 

 

附：Server Version: 17.12.1-ce