Keepalived PID file /**/**/**//var/run/keepalived.pid not readable (yet?) after start.

Keepalived的安装过程不说了，就是简单记录PID not readable的问题。原因不确认，只是解决方案。
使用的Keepalived版本为1.3.5
安装Keepalived后，启动时发现报错，使用命令journalctl -xe 查看日志，其中有此一行：
PID file /var/run/keepalived.pid not readable (yet?) after start.
这是由于没有按照Keepalived工具默认的路径配置造成的，解决方法：

1. cp keepalived-1.3.5/keepalived/etc/init.d/keepalived /etc/init.d/
2. mkdir /etc/keepalived
3. cp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/
4. cp keepalived-1.3.5/keepalived/etc/sysconfig/keepalived /etc/sysconfig/
5. cp /usr/local/keepalived/sbin/keepalived /usr/local/sbin/
   由于另一项配置需要改正，就是keepalived.service文件中的pid路径，修改为默认的路径即可，/var/run/keepalived.pid