cPanel DNS Only Setup

[sozotech]

Hello,

I inherited 4 cPanel servers where they also act as the DNS servers and have clustering setup. I would like to separate the DNS functionality out to dedicated DNS servers. I am fairly new to cPanel and wanted to ask some questions in regards to it's setup/architecture.

1) If I understand correctly the best setup is to have a direct link between each web server and each DNS server. On the web server side should I have the DNS servers listed as Standalone and on the DNS only server have the web server listed as Synchronize?

2) Should I also have direct links between each DNS server? Do I need any links between web servers? I assume NOT but just want to make sure I understand how the sync works.

3) In regards to moving new DNS only servers into the existing cluster, I assume there is no risk in syncing up an empty DNS server with the current web/DNS server which has all the zones? Do I need to break the any of the existing links on the existing cluster once I have the new DNS servers in operation?

Thanks in advance for answering my basic questions!

Eric

 

[cPanelMichael]

Hello

1) If I understand correctly the best setup is to have a direct link between each web server and each DNS server. On the web server side should I have the DNS servers listed as Standalone and on the DNS only server have the web server listed as Synchronize?

We do not recommend that you set up the nameserver to synchronize data to a web server. Instead, the web server should be configured to synchronize data to the nameserver. Full documentation on this is available at:

Guide to DNS Cluster Configuration

2) Should I also have direct links between each DNS server? Do I need any links between web servers? I assume NOT but just want to make sure I understand how the sync works.

No, you should not link DNS-Only servers to each other, or web servers to each other.

3) In regards to moving new DNS only servers into the existing cluster, I assume there is no risk in syncing up an empty DNS server with the current web/DNS server which has all the zones? Do I need to break the any of the existing links on the existing cluster once I have the new DNS servers in operation?

You can actually just add the new DNS-Only server to the cluster, and synchronize the zones from the web server to the DNS-Only server. You can remove the previous servers from the cluster when you are ready to use the new DNS-Only servers.

Thank you.

 

[sozotech]

Ok, I am still fuzzy on whether to set synchronize or standalone on each side. Is this how you would setup both sides in cPanel?

webserver1 -> dns1 (Role: synchronize changes), dns2 (Role: synchronize changes), dns2 (Role: synchronize changes)
dns1 -> webserver1 (Role: standalone)
dns2 -> webserver1 (Role: standalone)
dns3 -> webserver1 (Role: standalone)

Thanks,
Eric

 

[cPanelMichael]

Yes, that is correct, assuming the first part of each example is the server you are accessing via Web Host Manager.

Thank you.

 

[sozotech]

Yes, you are correct. The left hand column is the server I am configuring via WHM.

Thanks for you clarifying that.

Eric

 

[sozotech]

Ok, I enabled clustering and synchronized all the zones to all servers. One thing I noticed is that, in the /etc/named.conf each of the zones are listed twice like

zone "domain.com" {
type master;
file "/var/named/domain.com.db";
};

zone "domain.com" {
type master;
file "/var/named/domain.com";
};

Named seems to be running fine and answering queries for all the domains but I am wondering if this is a bug or why this would happen?

Eric

 

[cPanelMichael]

It's normal to see two entries for the zones in the /etc/named.conf file. The zones are likely listed under both the "internal" and "external" views.

Thank you.

 

[sozotech]

I have synchronized all zones from the current web/dns servers to the new DNS only servers. One thing I noticed is it appears to NOT copy over DNS zones that were manually added to the original server that do not have hosting setup on the local server. I did a push from the web/dns server in question via "Synchronize all zones to all servers" but I am still missing these manually added DNS zones.

Is there a way to get these additional zones as well or am I missing something?

Thanks,
Eric

 

[cPanelMichael]

When synchronizing the zones, try checking the following option:

"Synchronize zones that are not configured on this server"

Thank you.

 

[sozotech]

Should I do this on the source server or the destination (DNS Only) server?

Eric

 

[cPanelMichael]

You should synchronize the zones on the source server. The DNS-Only servers are typically configured as a "Standalone" role, so changes made on those servers are not synced to other servers.

Thank you.

 

[sozotech]

Thanks. That took care of it. Sorry for all the basic questions.