Searchguard Support for Nxlog

Hi All,
I am securing my ES cluster with SG. the logs are shipped using NXlog community edition. When I run my nxlog to ship the logs the error what am getting is :

`2017-03-21 13:10:36 ERROR SSL error, SSL_ERROR_SSL: retval 0, sslv3 alert certificate unknown,

To trust the nxlog should I create a nxlog user or any ideas?

Has anyone used SG for nxlog?