问题现象
查看 /var/log/dc-agent.log 发现有如下报错：
The event in requested index is outdated and cleared : the requested history has been cleared [16951/1501]
The event in requested index is outdated and cleared : the requested history has been cleared [16955/1501]
The event in requested index is outdated and cleared : the requested history has been cleared [16957/1501]
The event in requested index is outdated and cleared : the requested history has been cleared [16959/1501]
The event in requested index is outdated and cleared : the requested history has been cleared [16961/1501]
The event in requested index is outdated and cleared : the requested history has been cleared [16964/1501]
The event in requested index is outdated and cleared : the requested history has been cleared [16968/1501]
The event in requested index is outdated and cleared : the requested history has been cleared [16970/1501]
The event in requested index is outdated and cleared : the requested history has been cleared [16972/1501]
产生原因
dc-agent 程序会会监听etcd中某些key的value值变化，当长时间没有事件时就会报这个错误。
处理方式
重启dc-agent程序即可：
# 先停止dc-agent
pkill -9 dc-agent && ps -ef | grep dc-agent
# 重新打开
dc-agent -d -s http://manage01:4001