I had a situation this week where a VPS had to go down for a few hours for a much needed resource upgrade. The Hardware it was running on aparently didnt have the spare resources to allocate so the whole virtual machine (I assume thats what its called) had to be moved to new hardware.

That meant I had to spend a day backing up the critical accounts and setting them up on a new VPS temporarily, and changing the DNS for the domains to point to the new VPS. All in all a real pain.

Is there a way to have a permanent redundancy built in using DNS settings or some other method, so that if a VPS goes down and the main IP address known by the nameservers is unreachable, then the nameservers will try a second IP address that I would have set up to host a very recent backup of the first VPS?

Thanks

Hi there, there are ways of doing this however with 1 vps it will only protect you if your nameservers where to go down, for redundancy most often use a secondary site also to forward their visitors to if the main site or vps is down.

the easiest would be "Secondary DNS" a quick google search will find you many providers offering this service an example could be http://www.dyndns.com/services/dns/secdns/ (first result on google)

Hope that helps

I'm sorry. Personally I suggest you to go with a reliable provider.

If they can't assure you that they will can handle problems with professionality or under an agreemeent as SLA you should go to another provider.

yes , there is a way to create redundancy using configuration in dns server where is placed your primary domain name for your site.

SLA or not - MOST SLA's cover notified or scheduled downtime. When a host plans to update hardware, it's in the interest of the customer. More resources are always a good thing.


Setting up a secondary machine and pointing DNS etc is a viable option, as is just setting up a secondary server temporarily.

Setting up as CSN-UK stated would offer more reliability, just be aware that you're doubling your costs of operation.

Thanks for all the replies guys.

I did expect that the solution would be to have a second VPS in the picture, and I am very happy with that. These things arent really that expensive these days. A developer or system admins time just managing that one day of turmoil would pay for a vps for a year.

So, how do I go about setting that up at a DNS level, once I have my two VPS servers running? Having looked at the link and suggestions in the posts made I'm not really any wiser. The secondary DNS thing seems to be about preparing for a nameserver failure, where as what I want to do is get the nameservers to point to a second IP address if the first one is unreachable.

Regarding the reliability of the host - the downtime was because I requested a resource upgrade, but there were not enough resources available on the hardware used by my VPS to allocate what I asked for. So they had to move the entire VPS to new hardware in order to accomodate my request. I dont see that as a reliability issue with the host, as annoying as it may have been.

Thanks