Web Hosting Talk : Web Hosting Main Forums : Hosting Security and Technology : load balancing?

[AdamFinzel]

Hi

What is the ideal configuration for a load balanced network.

We are using SQL Server and Nt 4. Wea are looking to get 3 to 4 servers.

Should we have SQL server on one machine and then use three machines for serving web pages? or should we have one as a file system. Two as web servers and one as a SQL Server? What is the best configaration?

[allan]

Adam,

It depends on three things:

1. What you are trying to load balance.
2. If the servers are all the same or different.
3. What type of load balancing equipment you are using.

Let's assume you have 4 servers, all the same size. Its always best to have one database server (its actually best to have two database servers and load balance them as well, but we can't have everything ). You should also consider putting a firewall in front of the database server.

Since you are going to be doing a lot of ASP/CGI to query the database you probably want to use the remaining three servers to serve content. If you had one server that was significantly more powerful than the other two you might consider doing all ASP/CGI processing on that server and just use the other two for serving static content (HTML and Images).

If you are going to use the database queries to create session IDs, then you will want to use some sort of persistence based load balancing.

Depending on the types of service your ISP offers you might be able to save some money by looking into Server Side Caching (like the CacheFlow 725) and SSL Acceleration.

Hope this helps.

[Si-WHN]

a lot of setups are similar to the following:

database server
pageserver (actually code html output)
inline content server (ie images etc)

I agree with uuallan in saying that you probably should have 2 database servers if you're going to go down this track.

There are so many configs available for this type of thing. It totally depends in the end on what content you're going to be serving up.

regards,

Simon

[MikePalmer]

Here is a couple of suggestions. If you are looking for high availability and reliabity, use Windows 2000 Advanced Server. Advanced Servers is bundled with Windows Load Balance and Clustering Services.

You should set-up 2 SQL servers with a shared fibre or SCSI storage RAID system in a cluster configuration. Make it Active/Active clustering. This will give you high availabity of the SQL databases. If one server crashes, the other takes over.

Next you should set-up 2 web servers with internal RAID storage is a load balance configuration. This will help even out the web load and also provide for redundancy.

So for the optimal config, you need the following:

Microsoft Advanced Server
SQL 2000 Enterprise
4 Servers
1 Shared SCSI or Fibre channel storage cabinet.

Hope this help,

[allan]

Be careful when using the Advanced Server Load Balancing. Aside from the obvious problems associated with trying to do Layer 4 switching at the server level, Microsoft's Load Balancing service creates a lot of braodcast traffic, which can flood your network if it is not properly segmented off.