Service fleet speak doesn't work properly

I'm trying to install fleetspeak on the client machine and I have this error:

Jan 13 14:10:45 HML-HS-PRIUSNEW fleetspeak-client[1243934]: F0113 14:10:45.580085 1243934 client.go:40] Error in configuration file: unable to parse trusted_certs

What would be this certificate, where can I find it in the documentation?