Difference between Primary / Secondary DNS & DNS Domains

[emg1102_]

I hoping someone can clarify the below inquiry for me.

Can someone explain to me the technical difference and function served between the Primary / Secondary DNS fields and the DNS Domain(s) field.

The attached screenshot represents the carrier's configuration on their device for a gateway in Hong King that our users connect into when sitting in China.

Our primary DNS server in the market is 172.26.2.1, our secondary is 172.28.2.11.

We found that users sitting behind certain ISPs in the China market were subjec to DNS hijacking making it difficult to reach some devices on our network.

We found that that inclusion of na.<corporate domain>.local in the DNS Domain field enabled them to reach our North American file servers using FQDN.

Furthermore, we also changed the DNS search order to search "devices DNS servers first, then client."

Prior to adding this entry, the sole entry that existed in the field was  ap.<corporate domain>.local.

However, I'm trying to ensure that the inclusion of  na.<corporate domain>.local will not affect the way traffic is routed when destined for other servers outside of the North American region.

Therefore, I'd like to understand what exactly the DNS Domain(s) field does and how it relates to directing traffic to certain servers.

Any insight would be greatly appreciated.

[jayLaiz_ · Accepted solution]

Hi,

The dns domain is where you specify the dns domains in your environment for example it is needed to resolve hostnames/fqdn's of resources which user sare trying to access

If a resource is test1.na.domain.local, the resource is part of the na.domain.local domain.

In network connect, it looks at the dns domain list, if you have search device dns first, it is going to search the device dns and check if the resource is part of the domain that is first on the list and so on

adding the extra dns domain should not cause an issue as if a resource is in ap.domain.local and the resource you are trying to acecss is test1.na.domain.local. if the first dns domain is na.domain.local, it will not eevn try to resolve as it is not part of its domain and will fall back to the second dns domain in the list for name resolution

Regards,

Jay

[emg1102_]

Thank you so very much for the reply.

Can you clarify one more item for me:

What function does the Primary and Secondary DNS fields serve in this configuration?

What exactly do these fields mean technically and is there any level of relation between the primary / secondary DNS fields and the DNS domains field?

Thanks again.

[jayLaiz_]

Hi,

primary and secondary dns servers are name server computers where the record of your  DNS domain name is stored,generally applied to each newly registered domain.domain names can work with only one name server - the primary DNS. However, practice has shown that a domain name needs to have at least two name servers assigned in order to be available at any time. In case there is a problem with the primary name server, the secondary name server will be able to answer the online request for a particular DNS domain

For example, if my dns is 10.90.89.1 and the dns domain registered is test.com, it stores the records for each hostname residing in that domain.

I hope this resolves your query

Thanks,

Jay