Alright, I'll make one thing clear from the get go, i am not a TP client or customer, but I've been reading through the forums about all the informative things all of the intelligent staff members have been posting, and answering questions to.

Firstly, I'm sorry to all of you who may get neglected by my questioning (if answered),
Secondly, TP Staff, do not feel that this is an Urgent subject, and do not feel obligated to answer my question.

I simply have read a lot up on the forums about different solutions for different things, a lot of useful and exciting information, currently, i work for an ISP, who is now providing web hosting for its clients. We have a CPanel web server, doing DNS and everything else on its own, but, our RAID card died and we lost all of our data, the RAID card corrupted the data on the drives so our RAID 5 Array failed. This left my mind curious about a vast majority of solutions, as I've seen the Clustering option in CPanel, and I've read on here that it's for DNS only, but it makes me wonder a few questions to aid in my understanding.

DNS Clustering?
Does this just simply copy all of the DNS data from one physical (or virtual) server to another?

File/Web Hosting Clustering?
How does it work exactly? i know that r sync copies the files by changes (only coping the changed sections of the files if possible.

I want some hard knowledge behind me before i approach him.

So, here's a quick description of what i want to talk to my boss about doing.

Buying an Additional Server (or two)
Running the DNS on Both servers, keeping them both fully active.
use a Load balancing sonic wall router (or higher end).

Both servers run under the same IP Address and also have secondary internal IP address's (for syncing files) and having the first (or primary) server handle all incoming requests. so basically both servers act the same, just if the primary goes down, then the secondary will take over the communications of the data...

Is this possible at all? so that without ever dropping any data at all (maybe a packet upon look up of secondary server information), that it could work properly?


And again, for the staff, If this is of any Inconvenience Please Notify me. The only reason i ask this question, is all the data I've found on this website, is extremely detailed and feels very professional, I'm not the server administrator at my work place, but i do know Linux and networking fairly well.

Any Suggestions or Tips to help in my research if possible?

Thanks.
-Chris

Cpanels' built in clustering function is just for dns -- it's great though, but currently only for this one purpose. If you only run the dns-only version on another server or vps, then yes it just copies all the main server's dns info to the slave server. If you run the full version of cpanel on two or more servers and set them up to all be in a cluster, then any changes made on one are synchronized to the others, so adding a new account on any of the servers in the clusters updates the others (or a customer adding a subdomain, etc.)

As far as file/web clustering, it depends on the dynamic content your customers are serving. If it's plain html and images, it's pretty simple. But if they are running forums, blogs, and other things that are dynamic content modified every time the page loads, it can be a bit more complex in the setup required and the support or standard control panels.

Full clustering would be ideal.

A simple backup plan would probably be adequate too though -- it's unfortunate that you suffered the worst kind of catastrophic failure of your raid system, but this is pretty darn rare. Something like R1soft running in conjunction with a good hardware raid system would probably be plenty sufficient. The advantage of R1soft is that you can set it to backup at a very frequent interval (hourly) without a huge overhead.

Even more on the budget, using whm/cpanel's built in backup mechanism to backup to network attached storage or an offsite-backup server would probably be sufficient. (this would likely only be daily backups to off-server, and a major raid/server failure would result in a couple hours of downtime to restore the accounts in cpanel, but with the odds of the raid failing being fairly low, this is probably sufficient for most customers' needs and budgets)

P.S. I'll let the load balancing gurus step in now to tell you the ideal way to do it. I'm probably too budget conscious!

Thank you so much for your insight Jeff, the person in charge of our servers at first when it failed, thought it was just a bad drive, i mean what are the odds off a $200-300 raid card failing right? on top of that the server was built by one of my bosses family members, so it should have been good hardware, not rip off cheep parts, once we found out the raid card had freaked out, we realized that the worst-case-scenario had happened kinda bizarre, no-where in town had a raid card to bring the system back up with... hmm bizarre coincidence, anyways, the reason I'm looking for a load balancing solutions is that if by chance, one whole server dies, another will come back up.

Any other help, or insight would be appreciated.

There is no out of the box cPanel for clustering anything but the DNS and MySQL via the remote MySQL option.

If you want to look at your own solution you could look at something like DRBD or iSCSI paired with heartbeat for failover. That should let you do what you want but would require a backup server of the same specs doing nothing while it is running smoothly.

There are a few people with cPanel clusters out there and we have some partial clusters but it is not something very well documented anywhere.