Mirrored servers in data centers nationwide -- how?

Posted by Sysadmin Evstar on Server Fault See other posts from Server Fault or by Sysadmin Evstar
Published on 2011-01-08T22:16:43Z Indexed on 2011/01/08 22:55 UTC
Read the original article Hit count: 176

Filed under:

Mirrored servers in data centers nationwide -- how? I flunked my IT interview by getting this question wrong.

I thought that in the various metropolitan areas, an "http://google.com" request goes to the ISP's DNS server, which somehow returns an IP address for one of several geographically-nearby http servers, and then something internally rolls over to the next available local Google server. But then, I could not explain where the table of available local Google servers is actually cached, or the details of the IP address rollover. Or how they could manually take some server out of the rotation, from anywhere.

So, what should I be reading now so I can ace this question next time?

Also, what daemons run on these machines 24/7 to keep all those mirrored database disks synchronized?

© Server Fault or respective owner

Mirrored servers in data centers nationwide -- how?

Posted by Sysadmin Evstar on Super User See other posts from Super User or by Sysadmin Evstar
Published on 2011-01-08T21:08:59Z Indexed on 2011/01/08 21:55 UTC
Read the original article Hit count: 176

Filed under:

I flubbed my IT interview with Google by getting this question wrong. I thought that in the various metropolitan areas, an "http://google.com" request went to a local DNS server in a geographically nearby datacenter, which then returned an IP address for just one of several nearby http servers, which then rollover'd to the next local server, and I could not explain how or where the nationwide DNS kept its table of the available local servers cached, or how such a rollover happened. Or how they could manually take some server out of rotation, from anywhere. Fail. So, which Wikipedia page should I be looking at now so I can ace this question next time? And, what daemons run on these machines 24/7 to keep the mirrored database disks synchronized?

© Super User or respective owner

Related posts about dns