Management Console : Could not establish a Connection with the agent

HI,
When I tried to import a Database in the MC, I get this error, when I try to start the agent the process is succesful, but I can't see the agent process,
And when I tried to restart the agent , the message is
Stopping vertica agent: ./vertica_agent: línea 281: kill: (-422462) - No existe el proceso

Vertica Version:11.0
Centos 7.4