August 2nd, 2013, 05:51 PM
Backup Web & DNS Server
I would like to do the following, but not sure which (if any) of the existing DNS servers would work well for this, or if the idea would work in-general.
My company currently has 1 server that hosts about a dozen websites, and a few custom server apps for applications/services we sale. Short outages/downtime are not really an issue for us, but we would like to avoid long term outages, more than a few hours. In the past this could be that our ISP is down due to environmental issues, or our server has hardware failure.
We indent to have 2 backup plans:
#1 - A 2nd ISP at the same location, this will be used 1st when possible.
#2 - A backup/copy of the server at another location, with a different ISP as well. Used only if the 1st server has a hardware issue, or both ISPs are down at that location.
In either case, in order for traffic to go to either the 2nd ISP at same location, or the other server and ISP at the other location, we need all of the IPs for our domains to change.
I know there are "Dynamic DNS" providers out there, but we are worried that the cheaper ones will have their own outages, in which case we'll just be adding more outages due to their issues. The more expensive ones are well, just out of our budget.
So what we'd like to do is host the DNS ourselves, on the server (and backup server) we already have. If they are down, our DNS might as well be down as well. The thought is that each server would just always return its own IP address(es), and a short TTL, for every DNS query it receives. Then, in order to route traffic to one server or the other (or other ISP), all we would need to update is the NS (NameServer) record for the domains. Since an NS record is actually a domain itself, not an IP, that actually means we only need to update the IP of the domain we use for our NS record -- easy enough.
We have been looking at doing this with Windows DNS server (both our servers use Windows 2003 Server OS). The main problem seems to be maintenance though, and keeping the DNS records updated on 2 different servers, and not just an exact copy either, because each needs to have different IP addresses that they return for different domains.
Any ideas or suggestions/comments/etc very welcome. I know a lot about how DNS works from a programming and network traffic level, but have never managed a DNS server or had to deal with issues like this.
If only GoDaddy had an API so that we could quickly change all of the IP addresses for every domain... then we wouldn't need to host our own DNS. They also don't support very short TTL, but that is a bit less of an issue, since we aren't worried about short outages so much.
August 12th, 2013, 10:40 AM
Turns out this is not really correct. NS records are host names, but on the GTLD servers you need a glue record to map that to an IP, so the NS record might as well be an IP.
Originally Posted by shopguy
So, long story not so long... we are going to just try DNSimple (most likely, possibly some other one), because unlike GoDaddy and Network Solutions, they have an API that will make changing the IPs for every domain easy.