3rd Party/External DNS & changing IP addresses


#1

Hi guys,

Would really appreciate some help.

After some downtime earlier this year I’d like to host my DNS externally (eg. UltraDNS) to point to my hosting (a dedicated box) at Dreamhost - so if the DH network goes down for an extended period (and, crucially, the Panel is unavailable), I can simply switch my external DNS to point to another host and my site is back up again.

So… this would be pretty simple if the “Unique IP” Add-on was permanent, but it changes :frowning:

Have read online about delegating authority at external DNS hosts for subdomains, but am not clear if it works for primary domains (and will also introduce much more latency…?).

Has anyone else done this?

(Is the answer that I need to move hosting away from Dreamhost? Hope not! The support is great - happy customer for 10+ years).

Thanks in advance for any tips.

Chris

PS. First time I tried to post this question I got a “Bad Gateway” server error…?


#2

Anyone got any thoughts on this?


#3

I’ve been intending to do what you suggest as soon as enough of IPv6 is working so that one can just use that for linking together the DNS records at the other host and the website at Dreamhost.

Actually, come to think of it, haven’t we just had an “IPv6 day” or something like that?

Does anyone have an idea about how long we still have to wait?

~Tom


#4

I’m assuming this question is about shared hosting. (The answer is different for VPS and shared hosting, since those products both allow you to manage the httpd.conf file.)

With shared hosting this can be done with dedicated IP’s, and the expense of at least one domain that has dreamhost nameservers. This option however gets expensive quickly as each domain you forward in will require it’s own unique IP add-on. Let’s say you have 3 sites called example1.com example2.com and example3.com all with external DNS, and a 4th domain called d_dns.com that has dreamhost nameservers, thus allowing dreamhost to manage the DNS. You would then fully host example1.d_dns.com, example2.d_dns.com and example3.d_dns.com. Then add a unique IP to each on the of those 3 sub domains (a unique IP is only good for one sub-domain in shared hosting because you have no access to edit httpd.conf). Once you have done that, in your external DNS you would add CNAME records for example1.com -> example1.d_dns.com, example2.com -> example2.d_dns.com and example3.com -> example3.d_dns.com

As you can see however, this gets expensive quickly since each domain/subdomain forwarded in this fashion requires that you purchase a unique IP for it.

On the other hand if you are really afraid the dreamhost panel might be unavailable for a long time, another alternative (and probably much less expensive) is for you to decide what registry you think has enough redundancy that they wouldn’t be down for any extended period of time and transfer your registrations there. Once the registrations are transferred away just simply leave their nameservers as NS[1,2,3].dreamhost.com allowing dreamhost to manage the DNS. If the dreamhost network should become unavailable all you would need to do is log in to the alternative registrar and change the nameservers to point to whoever your new host is.

Many people purposely use alternative registrars for this exact reason (among others).


#5

Hi LakeRat,

Thanks for the reply. My query is actually about dedicated hosting. :slight_smile:

Basically I want a 3rd part DNS provider (eg. UltraDNS) to handle nameserving so that I can switch hosting (and propagate quickly) if there is another spell of chronic downtime at DH. I wouldn’t have a problem if DH offered static IPs, but the Unique IP add-on seems to change randomly…

I’ll take a look at your CNAME idea but would be slightly worried about Google penalising this kind of setup? Am also looking at switching to a host that offers perm IPs and more robust email handling. (Would be a shame though - have been with DH since 2000. )

Any DH staffers on here that could reveal if perm IPs are in the works?


#6

I don’t have a dedicated server to look at or play with, but i believe you can do this pretty easily with a dedicated server by turning off dreamhost management in the panel and maintaining your apache httpd.conf yourself. The relevant apache doc seems to be: http://httpd.apache.org/docs/2.2/vhosts/examples.html

FWIW, This is really why CNAME records exist. It’s true google does penalize for duplicate content (meaning two or more domains serving the same content). Untouched my example above for shared hosting would create that situation, however that to could be solved by creating a redirect (in shared hosting via .htaccess) to solve that problem. I have a real world example where this is setup but because it’s not my site I won’t post the information publically, but if you email me using the button below this post I’ll give you the details.