Here are some steps put together for setting up load balancing on a SharePoint farm with Windows Server 2008.
Let the steps to configure load balancing commence…
1. Install Network Load Balancing Feature on each Web Front End
On each front end in the farm, within Server Manager, add the NLB feature:
Wait a bit:
2. Add a New Cluster
Through the start menu, Administrator Tools, click Network Load Balancing Manager:
Right click Network Load Balancing Clusters, and choose New Cluster:
Type the IP address of one of the web fronts in the farm to serve as the first host in the cluster:
Leave the defaults and click next again:
3. Set Cluster IP Address
This IP Address is the dedicated IP address for the cluster and is what DNS will point to, to get load balanced between the front ends. On the Cluster IP Addresses box, click Add and type an available dedicated IP address and subnet mask:
Optionally, you can setup many clusters IPs for fault tolerance purposes, but for most cases you'll just have one:
4. Specify Cluster Parameters
Select the Multicast operation mode, and click next:
5. Specify Port Rules
Click edit on the default port rule:
Deselect the "All" checkbox, and choose the Network filtering mode:
After finish, the NLB manager will show it has begun the configurations changes. If you're in a remote desktop to the server, you'll lose your connection temporarily while it re-configures:
6. Add Any Additional Hosts to the Cluster
Now that the cluster is ready to go, you can add additional hosts/web front ends. Right click on the cluster IP address and click Add Host To Cluster and type the IP of another web front end in the farm. Repeat until they're all added.
Some SIde Notes:
if you get "Could not locate NLB on the specified computer" you must first install the load balancing manager feature. See step 1.
Here is a good resource that shows how to implement Network Load Balancing (NLB) and Round Robin.
The article says its for Exchange...but it definitely applies to SP as well.
Personally, if I had to choose between the two...it would be NLB. However, the DNS solution is a breeze to setup.
As for the SharePoint side of things, there isn't any further configuration required. Just simply configure load balancing from one of those methods and then start building more than one SharePoint server that holds the Web role.
Also, as an FYI Joel has a good post for troubleshooting NLB as well as some "tips" that are worth perusing through. It's an older post, but I don't think NLB has changed much with Windows Server 2008 from 2003.
Thanks to Joel and Phil for the above info