Understanding dig output - will this redirect a browser?

Question

I'm trying to setup a subdomain elstest1 on my example.com domain to redirect to a certain IP. Following some instructions on the web, I created an A DNS record.

Currently, if I do this:

dig elstest1.example.com

I get:

...
...
;; ANSWER SECTION:
elstest1.example.com. 14400  IN      A       994.93.999.990

(IP address hidden)

Will going to http://elstest1.example.com take me to the IP address above?

Its not working presently, but that's to be expected because the web server isn't up + I just made the DNS changes, etc. But I want to make sure the above DNS settings are what they need to be.

Answer 1

First, you've created an alias, not redirect. Alias points to IP, not redirects to it. Actually, all domains are aliases.

Second, changing DNS records takes some time. From 15 minutes to 1-2 days. It happens because there are lots of DNS servers in the world, and they all have to be updated.

Will going to http://elstest1.example.com take me to the IP address above?

Indeed, after your ISPs DNS will update.

Answer 2

Yes, your record is correct - that's exactly what an A record would do.

If this entry is brand new it should be visible very quickly across the rest of the internet. So called "negative answers" (i.e. "this domain does not exist") are usually only cached for 15 minutes or so, or at worst a few hours. See RFC 2308.

If the entry previously existed, but only just got this value it might take longer, depending on the (previous) value of the TTL. To be on the safe side it's normally suggested that it takes up to a day or two for all caches to flush the previous entry and then pick up the new one.