2 Servers - 1 cPanel - Load Balancing

[fulleffect]

Hi,

I currently have a dedicated server, with cpanel, and recently had a network outage, resulting in the ecommerce site being down for several hours.

Not good for business...... So my question is, if i bought a second server with another host, how can i implement a fail safe system, where by

1. The primary server serves the shop 24/7
2. In the event of a server crash or network failure, i can switch to the secondary server
3. Can i use 1 cpanel to do this, or do i need 2?
4. What software would you use to make the switch?
5. Are there any other better ways to do what i need?


Thanks in advance!

[speed]

Originally Posted by fulleffect

1. The primary server serves the shop 24/7
2. In the event of a server crash or network failure, i can switch to the secondary server

Look at the failover system at DNS Made Easy when it detects the main server down it updates DNS to point visitors to the 2nd server.

3. Can i use 1 cpanel to do this, or do i need 2?

No, cPanel is installed per server, having said that I guess you could write custom scripts to copy setup from the cPanel server to the backup server and have them update Apache etc.

4. What software would you use to make the switch?

DNS made easy should take care of switching to the back up server and back to the main one once it's running again.

However you are going to need something to keep the 2 copies of the site in sync, assuming you store order information on the server then you're going to need to keep the databases in sync and then catch the failed one up, possibly merging data from the 2 back into one. Think this sounds easier than it is.

You're going to need the sync to happen without having to take the service offline, you'll probably end up having to have your e-commerce software modified to support this.

Note: The above is failover rather than load balancing that is only one server is live at a time. If you want to load balance then normally you do it within the same data center using special hardware.

For load balancing both servers would be serving data and if one fails the other takes over all the work, however if the network fails you're down again, although if the host has many providers this shouldn't be that frequent.

[imvain2]

For merging Databases, there are a few solutions.

It really depends on your budget, preference and ecommerce application abilities.

In theory, the "easiest" and least expensive way to accomplish this is a basic 3rd server, which doesn't have to be dedicated.

The 3rd server could be the online order center. Where all of the order details are store and accessed. So both ecommerce servers would store the orders on the third server.

This way, no matter what ecommerce server goes down and when, there will be a central storage area.

**
Of course NO solution is the perfect solution, so there will be flaws or "what ifs" in ALL solutions.

[speed]

Originally Posted by imvain2

In theory, the "easiest" and least expensive way to accomplish this is a basic 3rd server, which doesn't have to be dedicated.

Then this is a single point failure and therefore the other 2 servers are pointless therefore may as well stick with a single server.

[sanver]

Managing downtime for an enterprise application or an e-commerce sie is certainly a mater of priority today for Webmasters. Of-course choosing the right data center or the web hosting company can take care of lot of risk associated with downtimes.

Having alternate DNS is certainly a good step provided the otherDNS points to a live replicate sever. Replicating coding part of the application maynot be a very difficult task. For Databases, nearly al databases provide for a way to replicate it. For MySQL, you may like to go through MySQL :: MySQL 5.0 Reference Manual :: 16 Replication and for MS-SQL, you may like to go through Microsoft SQL Server - Wikipedia, the free encyclopedia so on....

You need to calculate the cost of your downtime is decidicng how much time and money you are going to spend on setting up fail safe alternative server.

All the best!

[Orion]

the DNS route is a great, simple easy way to go.. simply use name servers to point to main and sub server however if the site is dynamic and you need to track everything it will not be sync'd nor balanced...... for that you need a proxy system in between (effectively a 3rd server) dns points to the proxy in the middle which then routes traffic based on load parametres you've previously determined. This system can also be set up to sync the data / orders etc. between the two servers .. it is fairly expensive way to go, but definitely is the best, it's what most enterprise level sites do.