Solved

NLB for terminal server not working

Posted on 2011-09-27
10
662 Views
Last Modified: 2012-06-22
I have 3 win 2k3 servers that I want to use NLB  as a terminal server farm. These are all VMs on vsphere, and I know that shouldnt make much of a difference.

I was going to use multicast, as that seemed to be the best way.

I installed NLB on each server, then set the cluster IP and the cluster name on each, set them to multicast, and then set the priority.

The MAC it shows seems to be the same for 2 of the machines, and the 3rd is different.  After I added this to the 3 machines, when I connect to the cluster, only 1 allows connections, when I look at the other 2, it states acquiring network address.  It gives an IP Conflict message,

I did add (as per the insructions I saw) the cluster IP into each server as a 2nd IP after installing the NLB.

I ended up having to turn off the NLB from 2 of the machines, and let just one of them keep the cluster IP so people could still connect to it.  I am not certain of what is going wrong.  I was able to ping each of the servers actual IP address, and could reach each via RDP before the NLB config.

I have a cisco 3750 switch, and I did add an static arp statement, which pointed to what I assume was the cluster MAC, each server showed the same MAC for the most part, but one had 01, and 2 had 02 as the first characters in the MAC.  I used what they gave, but replaced the first 2 characters with 00 for the arp statement.

Any ideas??
0
Comment
Question by:Wayside_Tech
  • 5
  • 4
10 Comments
 
LVL 39

Accepted Solution

by:
noci earned 333 total points
Comment Utility
Switches are designed with the assumption that MAC addresses are unique world wide.
So having seen on packet from one system, that would indicate wich portshould be used.

Switching between ports can cause a lot of problems with packets ending up in the wrong session.
AFAICT a HUB should be useed for this type of configuraton

0
 
LVL 1

Assisted Solution

by:Kareem_ElBably
Kareem_ElBably earned 167 total points
Comment Utility
why dont you use Unicast mode with 2 network cards it is much better
also check ARP configuration on the link below

http://www.cisco.com/en/US/products/hw/switches/ps708/products_configuration_example09186a0080a07203.shtml
0
 
LVL 1

Author Comment

by:Wayside_Tech
Comment Utility
Since these are VMs, it would be challenging to have the ports connected to a hub before the switch.   The problem with unicast is the same, as per Vmware, they should be in multicast mode.  If they were physical machines, I could understand that..
0
 
LVL 1

Author Comment

by:Wayside_Tech
Comment Utility
One thing I noticed, is that there is an admin tool for NLB, is that a better choice to use to setup the cluster instead of individually on each server?
0
 
LVL 39

Assisted Solution

by:noci
noci earned 333 total points
Comment Utility
Then the mac-addresses need to have an odd first byte, that bit signals the presence of multicast traffic.
0
How to run any project with ease

Manage projects of all sizes how you want. Great for personal to-do lists, project milestones, team priorities and launch plans.
- Combine task lists, docs, spreadsheets, and chat in one
- View and edit from mobile/offline
- Cut down on emails

 
LVL 39

Expert Comment

by:noci
Comment Utility
I meant the effective MAC addresses for the cluster alias.
0
 
LVL 1

Author Comment

by:Wayside_Tech
Comment Utility
how do I determine what the cluster MAC would be?  I didnt see it anywhere.  I assumed what it was, but not sure.
0
 
LVL 1

Author Comment

by:Wayside_Tech
Comment Utility
I figured it out.  NLB display gave me all sorts of stats, and I used the NLB manager to get it up and running and it works great.
0
 
LVL 1

Author Closing Comment

by:Wayside_Tech
Comment Utility
i figured it out on my own, assigning points because they are earned,,...
0
 
LVL 39

Expert Comment

by:noci
Comment Utility
Thanks.
0

Featured Post

How to run any project with ease

Manage projects of all sizes how you want. Great for personal to-do lists, project milestones, team priorities and launch plans.
- Combine task lists, docs, spreadsheets, and chat in one
- View and edit from mobile/offline
- Cut down on emails

Join & Write a Comment

Many of us need to configure DHCP server(s) in their environment. We can do that simply via DHCP console on server or using MMC snap-in on each computer with Administrative Tools installed in a network. But what if we have to configure many DHCP ser…
ADCs have gained traction within the last decade, largely due to increased demand for legacy load balancing appliances to handle more advanced application delivery requirements and improve application performance.
Illustrator's Shape Builder tool will let you combine shapes visually and interactively. This video shows the Mac version, but the tool works the same way in Windows. To follow along with this video, you can draw your own shapes or download the file…
Get a first impression of how PRTG looks and learn how it works.   This video is a short introduction to PRTG, as an initial overview or as a quick start for new PRTG users.

772 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

10 Experts available now in Live!

Get 1:1 Help Now