Need of secondary and Tertiary Servers in LINUX

[nsvora]

Hi All,
I am working on the proprietory Dynamic DNS client implementation . My DHCP and DDNS server are running on LINUX and would like to know some information about Secondary & Tertiary DNS Servers.
Currently, my client send the update to only Primary DNS server.

Could anyone kindly answer the following :
Why do we need secondary and tertiary servers?
My understanding regarding them is that :
- Any client sends the update only to the Primary DNS server.
- Primary server updates the records to secondary and tertiary.
- Any DNS Queries can be answered by any of the primary, secondary or tertiary servers.

Should client send the update record to secondary DNS Server if primary is not reachable?

Thanks in advance,

With Regards,
nsvora

 

[lgarner]

The DHCP server, not the client, sends the update for DDNS to the zone master, or "primary". The master DNS server will update the slaves.

The multiple DNS servers that are configured on the client are just for failover.

 

[nsvora]

Thanks for your reply lgarner.

I understand the redundancy required for the updates to go throught we need two servers.
I have proprietory implementation of DHCP and DDNS client so i dont want to have DHCP server updating the DNS server.

So in this case, should DDNS client be sending these updates to secondary if primary is not reachable?