How are you doing?
Sorry, but I am very confused here ...

We have 2 nagiosxi servers - rmfv170nxi1b & bmds171nxi1p. We have recently rebuilt bmds171nxi1p and took a backup from rmfv170nxi1b and restored on bmds171nxi1p. We Nagiosxi monitoring configured on each nagiosxi to monitor other server.
Please let me know which rmfv170nxi1bor bmds171nxi1pNagios xi server is having issue?
Do you have issue on ALL services check or just this "rmfv170nxi1b" service only? .... on which Nagios xi machine?
May I see the command used to check this "rmfv170nxi1b" service?
Nagios xi GUI > Configure > Core Config Manager > Services
Now, select the "rmfv170nxi1b" service > please click "Run Check Command" > Click "Run Check Command"
Now, please copy the command and outputs and post them here.
Best Regards,
Vinh