DNSmanager + ISPmanager?

[MrNobody]

Is there any specific point to use DNSmanager if I already have ISPmanager installed?

[ksenya]

You may use only ISPmanager for DNS configuration, or integrate ISPmanager with 2 DNSmanger.
In this case name servers should locate on different physical servers that are located in different places. This will provide better security of the DNS system and ensure that your domain names are always accessible.
The risk that two servers in different parts of the globe are not accessible at the same time is considerably low.