Backup page for when your site has to go down for whatever reason


#1

So today my website went down, I wasn’t expecting it to, and the support said it was due to a faulty hardware and unhappily it was out of my control…

Then I tough to myself, hell DH is so great why it doesn’t have a backup server that allow us to show a custom page, that we can customize on our control panel with some message/html/whatever, for example:

“Hey our website is down for a schedule maintenance check back later!”

Or something alike…

This is my scenario on today’s issue, the DNS was working properly, given that, it would not trigger secondary DNS in case you had one setup.

I could have changed the IP of the domain redirecting it to another service to show the said above mentioned page, however, since it requires the DNS to propagate, not all users would be seeing the same page, right? Which would be a problem and then you have to set the IP back to resume the services, which is an annoyance due to the DNS propagation.

However if DH was to have a backup server for such issues where when our sites have to go or are down for whatever reason they can simple turn a switch and even make that switch available to us in case we need, that would simple redirect the domain to a backup server with that custom page, which we can customize in our control panel, that did be awesome!

Thus even if our domain server goes down, we are still able to reach our clients and users with a message about what is going on or to keep em up to date.

Hope you consider and accept my suggestion.

NOTE: Basically it would work as a secondary DNS for when your DNS is still responding… As mentioned above a secondary DNS will not be reached unless the primary DNS times out, but that does not take into account the web server of your domain’s DNS, AFAIK, but feel to correct me here.


#2

It would be awesome if that functionality was built into DNS, but it’s not.

The functionality you’re speaking of takes 2-3 times the computing capacity to implement, and it’s not actually failsafe unless scaled much larger than that. In short it’s not worth it with average 99.99% uptime.


#3

I use Cloudflare for all of my sites. Cloudflare has a “Down” page. It looks like this:
http://cloudflarepreview.com/preview-cpage?act=preview&target=always-online%3Ano-copy

On a paid Cloudflare account, you can create a custom page. As a side note, Cloudflare has an Always Online feature (on free and paid plans), so if your site is down, Cloudflare will show the last cached version.


#4

That functionality is built into DNS.
And yes, the internet is awesome.
When the web browser does a hostname lookup, the DNS server (if properly set up) returns a list of IP addresses.
Modern web browsers try the first IP address on the list, and if it times out, tries again with the next IP address on the list.

At your favorite command line, you can see for yourself – both “nslookup cnn.com” on Windows and “host cnn.com” on Linux return the list of IP addresses.

“Using multiple A-records for my domain - do web browsers ever try more than one?” http://webmasters.stackexchange.com/questions/10927/using-multiple-a-records-for-my-domain-do-web-browsers-ever-try-more-than-one
"The internet was designed so that if parts of it were wiped out the network would still function. Multiple A records were designed for this reason." – Dave Gibelli https://bugzilla.mozilla.org/show_bug.cgi?id=565862
"Creating a DNS Record for a Host with Two or More IP Addresses" https://support.microsoft.com/en-us/kb/168321
"https://support.microsoft.com/en-us/kb/168321" http://stackoverflow.com/questions/6971556/is-host-name-to-ip-a-one-to-one-mapping
"Using DNS for failover using multiple A records" http://stackoverflow.com/questions/5319649/using-dns-for-failover-using-multiple-a-records
"Round-robin DNS" https://en.wikipedia.org/wiki/Round-robin_DNS


#5

I agree that browsers will check multiple IP’s for a site, you can serve a site from any number of IPs for redundancy, and yes that is what DNS does. I also agree that its Round-robin.

But you can’t serve an alternate maintenance page that way, which was the OP’s request. There is no order, no priority, it’s round robin. no primary, secondary IP’s. A first time visitor just might get the maintenance page when the sites fully up and running.


#6

When a modern web browser first visits a page, it tries the first IP address on the list it gets from DNS, and if it times out, tries again with the next IP address on the list.
The first IP address on the list is the primary IP, the second one is the secondary IP.
If you wanted to do round-robin, you could set the rrset-order (or the equivalent in any modern DNS server) to “cyclic” or “random”, but it sounds like the original poster wants rrset-order set to “fixed”.

Alternatively, if the original poster is happy with manually “turn a switch” rather than completely automatic, when things are running normally the backup computer could somehow be disconnected from the public internet. So no matter what the rrset-order – even if the DNS is set to round-robin – a web browser that picks the backup IP will time out and try again with the primary IP. When the primary computer is offline, someone could manually “turn a switch” to temporarily connect the backup computer to the public internet until things are back to normal; and everyone’s web browser will (after a short timeout) see the backup computer, without waiting for DNS to propagate the backup IP address.
(Once it is set up, this “turn a switch” is fairly easy to do by clicking checkboxes in the firewall router, without touching the configuration of either the primary or secondary computers. Other methods of implementing this “turn a switch” may be easier to set up).