DNS Clustering Questions

[JayFromEpic]

I’ve read through a few past threads regarding DNS Clustering and just GD a couple of questions if anyone has the knowledge to share.

I am planning a new dns cluster that is intended to be spread across 5 North American Geo locations and 5 European Geo locations.

My question is, in this case, do I need to create 10 total dns name servers to use for this or can I create duplicate instances in the 10 locations providing the backbone for a typically seen setup, for example dns.domain.com and dns2.domain.com and each domain name server has its own instance in all 10 locations.

I am still in the planning stages of creating this and want to make sure I am going about this correctly and understanding the architecture behind it.

As well, when converting existing cPanel web servers over, will these go through a DNS propagation period and will I need to resynchronize existing dns records?

Lastly, when switching existing cPanel servers over, I read that you set these to a standalone setting and only the clusters themselves to synchronize. I want to make sure I am understanding this correctly.

I really appreciate any help with this, just look to clarify a few things before I start setting up this cluster configuration.

 

[cPanelMichael]

Hello Jay,

I recommend taking a look at our Guide to DNS Cluster Configurations document if you haven't done so. It provides a helpful overview of how to setup a DNS cluster.

I am planning a new dns cluster that is intended to be spread across 5 North American Geo locations and 5 European Geo locations.

My question is, in this case, do I need to create 10 total dns name servers to use for this or can I create duplicate instances in the 10 locations providing the backbone for a typically seen setup, for example dns.domain.com and dns2.domain.com and each domain name server has its own instance in all 10 locations.

Good question! The clustering features offered in cPanel & WHM do not provide for automatic failover functionality on individual name servers. Thus, you can't have multiple IP addresses assigned to a single name server (with the intention to automatically switch the name server from one IP address to another in the event that name server stops responding). Instead, you'd have to use a single IP address for each individual name server.

As well, when converting existing cPanel web servers over, will these go through a DNS propagation period and will I need to resynchronize existing dns records?

The existing and new DNS zones will automatically sync to the servers configured as part of the DNS cluster, depending on the assigned role. You can review the available DNS roles at:

DNS Cluster - Version 74 Documentation - cPanel Documentation

The DNS propagation will occur once you change the name servers assigned to a domain at it's domain registrar, or when changing the IP address of an existing name server at the registrar. Once those changes propagate, the changes you make to the DNS zones on the cPanel & WHM servers will automatically sync to additional servers in the DNS cluster (the reload time generally only takes a few seconds, though servers with large amounts of zones can take a little longer).

Lastly, when switching existing cPanel servers over, I read that you set these to a standalone setting and only the clusters themselves to synchronize. I want to make sure I am understanding this correctly.

I recommend using the "Direct Links" example at:

Guide to DNS Cluster Configurations - cPanel Knowledge Base - cPanel Documentation

Thus, your cPanel & WHM hosting servers "synchronize changes" to the name servers, and the name servers are "Standalone".

Let me know if you have any additional questions, or need clarification on any of my answers.

Thanks!