Someone explain DNS, nameservers, registrars, MX, cname, A(host)?

[fuzzybabybunny]

Here's what I've got:

1. domain name registered with GoDaddy (mywebsite.com)
2. website hosted through Amazon EC2
3. email goes through gmail

Can someone explain to me how registrars, nameservers, and DNS records are connected?

- I register a domain name with GoDaddy. GoDaddy is the registrar.
- The nameservers are from GoDaddy.
- The GoDaddy DNS Zone file configures how the GoDaddy nameservers respond to requests from browsers, right?
- Inside the zone file:

A(Host): points "mywebsite.com" to the IP address of the Amazon instance that's hosting the website contents.

CName: configures where the subdomains go.
ex. The "www" subdomain gets forwarded to mywebsite.com
ex. The "ftp" subdomain also gets forwarded to mywebsite.com

MX: really fuzzy on this, if someone sends an email to "name@mywebsite.com" the MX entry determines which servers handle this request, right? So I need to configure these to point to Google's servers.

Moved from Programming to Networking -- Programming Moderator Ken g6

 

[sourceninja]

...

 

[kevnich2]

What server traffic goes to for different methods (website requests, email, etc) is all handled by DNS. The registrar tells the root name servers what DNS servers are authoritative for your domain. The DNS servers then tell the rest of the internet the actual details regarding your specific domain, such as A, cname and mx records.

You can have one server that handles your website, which relies on cname and host/A records. You can have another server handling your email, which is through the mx records, SPF records, etc.

You seem to have a grasp on the important things but as your post indicates, yes your MX records need to be configured per google apps specs so the email gets handled by their servers.

 

[fuzzybabybunny]

I see. Part of my confusion is that another one of my domains is registered on GoDaddy, but somehow the nameservers are ones provided by my hosting company (not GoDaddy). Can I choose to have GoDaddy be the nameserver for this domain instead? I like their DNS management console better and its nice to have everything for my domains in one spot.

 

[Jamsan]

I see. Part of my confusion is that another one of my domains is registered on GoDaddy, but somehow the nameservers are ones provided by my hosting company (not GoDaddy). Can I choose to have GoDaddy be the nameserver for this domain instead? I like their DNS management console better and its nice to have everything for my domains in one spot.

Yes, you can. For every domain, the authoritative domain is configured by what's specific for the "name servers". These name servers dictate who is authoritative. Go to your existing DNS provider and look for that setting. Make the change over to the Go Daddy records and it will then use the zone configured in Go Daddy to server up all the DNS records.

Word of wisdom - make sure your zone for your domain served up by the other provider is configured first with all your appropriate A records, CNAMEs, MX, etc. BEFORE you change the name servers. If you don't you run the potential risk of DNS lookups starting to occur with Go Daddy, but no actually DNS records existing there.

 

[kevnich2]

As jams an indicated, yes you can easily switch your DNS provider to godaddy but I have to also point out the same thing, when you switch, make sure and setup godaddy DNS identical to that of your existing host. Then wait atleast 48 hours before making any other changes. It takes 48 hrs for authoritative DNS changes to propogate through the Internet. Also might want to set your ttl lower for a little bit (say 60) before you begin making changes so that you can revert quickly with minimal downtime. Once you know it works, adjust the ttl back up higher so your DNS isn't being hit hard.

 

[fuzzybabybunny]

Thanks. I don't think I can make preemptive DNS changes in GoDaddy for my domain - I get an error that says the zone file is unavailable because my domain's name servers do not belong to GoDaddy.

 

[kevnich2]

Thanks. I don't think I can make preemptive DNS changes in GoDaddy for my domain - I get an error that says the zone file is unavailable because my domain's name servers do not belong to GoDaddy.

No you have to change the DNS servers to the godaddy one's then allow about a minute to go by, then go into the dns records and from there you'll be able to change the dns settings around. Godaddy doesn't allow the records to be modified unless it detects that it is the authoritative dns provider. I don't actually know the reason behind this as it really doesn't matter but it's how they're configured to act right now.