Multi-Hosting

One Site - Two Hosts?

[Napoleon]

A domain name of course has a primary and secondary nameservers specified in the DNS.

Presumably, the second is used if the server for the first is down or if there is a problem.

I wondered if anyone had any experience with the following.

Nameserver primary I point at Hosting-Company-1. Nameserver secondary I point at Hosting-Company-2. Both hosting companies are ready to receive the same domain.

Would this work? If Hosting-Company-1 goofed, would the system revert to Hosting-Company-2 and display that copy?

Anyone tried this?

If it does work, any suggestions regarding the impact on Google (if any)?

[DaveAtIFG]

I have no first hand experience, perhaps some one else does?

It sounds like completely workable setup to me and I don't think the SEs will have a problem with it.

[chris_f]

If your primary name server is working it will use that regardless of weather your site is operational or not. It will only switch to the secondary nameserver if the primary nameserver cannot be reached.

[incywincy]

probably showing my ignorance here but i thought that although you can specify a primary, seconday and even tertiary nameserver these nameservers should only point to one unique i.p. address for the webspace. if your primary and secondary nameservers point to different i.p. addresses won't this cause confusion somewhere along the line? this would be especially true if you had a database.

[przero2]

I am seriously considering this option of using different hosts for primary and secondary?. Could any one point if there will be any concerns with primary and secondary DNS having different IPs? Thanks.

[Lisa]

The only concern with have two different IPs is that some clients receive one and some will receive another. Primary doesn't mean it gets used first. The order a client looksup your name servers can be in any order. So don't assume they will always find the first site.

Another thing to be concerned about is the TTL. My computer will relookup the IP address after the TTL expires. So, I may be browsing your domain and then suddenly directed to a different IP. I should notice the difference but your software may have hiccups with this.

[scotty]

I think from the end-user point of view, there is no such thing as 'primary' or 'secondary' name servers -- they are just host names listed under the NS section of the zone. Therefore clients can query any NS from the list. Only the name servers know about themselves, so that the secondary knows where to do the zone transfer...

And Lisa is right - what happen if the IP address changes in the middle of browsing, say, a transaction? The applications on both hosts will be very confused. TTL is usually set to 12-24 hours (at least for my domains), and I believe browsers will normally cache the DNS results. However, just in case a glitch happens...