"Connection rejected, time mismatch too great" ??

[Abu Abdulla alhanbali]

I got this in my failover setup:
Failover CONNECT to dhcp-failover rejected: Connection rejected, time
mismatch too great.

I tried to sync the clock by running the xntp process in both machines
without success. Any Idea of how to solve this.

in addition, What is the distance between the two servers. We have a setup
in which the primary server in one city and the secondary in another city?

Please advise on that.

Greatly appreciated.
Abu Abdullah