CONFIGURING MNLB FOR LOAD BALANCING

EXCHANGE 2013 CU2 CAS SERVERS FOR HIGH

AVAILABILITY

INFRASTRUCTURE CONFIGURATION

2 CAS Servers Virtual Machines running on Hyper-V Windows Server 2013 R2 Generation 2 each CAS Server has 2 NICs one is for Public Access (LAN

NIC) and one for NLB (NLB NIC) both NICs are in the Production Network

192.168.1.0

HYPER-V VIRTUAL MACHINE FQDNS ARE:

CAS1.mvatcybernet.com 192.168.1.4 LAN NIC | 192.168.1.104 NLB NIC

CAS2.mvatcybernet.com 192.168.1.5 LAN NIC | 192.168.1.105 NLB NIC

MNLB NAME: cybermail.mvatcybernet.com 192.168.1.3

EACH HYPER-V VIRTUAL MACHINE HAS 2 NIC

CONFIGURED AS FOLLOW:

CAS1.mvatcybernet.com LAN NIC: 192.168.1.4

CAS1.mvatcybernet.com NLB NIC: 192.168.1.104

CAS2.mvatcybernet.com LAN NIC: 192.168.1.5

CAS2.mvatcybernet.com NLB NIC: 192.168.1.105

CAS1.mvatcybernet.com LAN NIC: 192.168.1.4 configuration

CAS1.mvatcybernet.com NLB NIC: 192.168. 1.104

CONFIGURE NLB CLUSTER

1. This should be the Secondary NIC for NLB but in the same

Production Network.

2. Configure the IP Address and Subnet Mask and DNS.

In Advanced’s DNS tab, confirm checkbox for Register

this connection’s addresses in DNS is unchecked

In Advanced’s WINS tab, ensure Disable NetBIOS over

TCP/IP is checked

3. NLB Configuration Steps:

Validate required NIC Binding order on CAS1 and CAS2

Otherwise, reorder the NICs so they occupy the first and second positions

Save settings by clicking OK and close Network Connections Applet

INSTALL NETWORK LOAD

1. Click on Start | Administrative Tools | Server Manager Click on Features | Add Features In the Add Features wizard, check Network Load Balancing checkbox Click Install

2. Close once installed.

CREATE A NEW NLB

1. On CAS1, click on Start | Administrative Tools | Network Load Balancing Manager

2. From the NLB console, right‐click Network Load Balancing Clusters

3. Click New Cluster 4. In Host field, enter CAS1 FQDN;

cas1.mvatcybernet.com click Connect

5. Choose the NLB NIC (Interface IP 192.168.1.104);

click Next | Add

6. In Add IP Address dialog box, enter 192.168.1.3 on

IPv4 address 7. For Subnet mask, enter 255.255.255.0; click OK |

Next 8. In New cluster: Cluster Parameters dialog box,

confirm Custer IP Address 9. On Full Internet name, enter Cluster Name

“mail.domain.com”

10. On Client operations mode, choose Unicast; click Next

11. In Add/Edit Port Rule dialog box, allow all port then Click Finish

12. Allow the new NLB cluster to converge; after convergence, the cluster status should say Success and with a GREEN icon next to it.

13. From CAS2, confirm Cluster Name “mail.xxxxxxxx.com” responds with the cluster

IP 192.168.1.3; otherwise determine DNS issue and resolve the issue.

14. Add the Second Node to NLB Manager Console. 15. Right‐click mail.xxxxxxxx.com Cluster Name 16. Click Add Host to Cluster 17. Type in Server 2 FQDN cas2.xxxxxxx.com in the Host

field then click Connect

18. Choose the NLB NIC (Interface IP 192.168.1.105) then

click Next and Next 19. Leave all settings at default; click Finish 20. Allow CAS2 to converge with the cluster; after

convergence, the cluster status should say Success and with a GREEN icon next to it

VERIFY NLB:

1. Stop Windows NLB service on CAS1 then from CAS2, confirm mail.xxxxxxx.com name responds with the cluster IP 192.168.1.3 and page is opening; otherwise determine and resolve the issue.

2. Restart Windows NLB service on CAS1 and allow the Cluster Nodes to converge successfully.

3. Stop Windows NLB Service on CAS2 then from CAS1, confirm mail.xxxxx.com responds with the cluster IP 192.168.1.3 and page is opening; otherwise determine and resolve the issue.

4. Restart Windows NLB Service on CAS2 and allow the Cluster Nodes to converge successfully.

CONFIGURE THE MAC ADDRESS TO THE VM NLB NIC

If you have virtualized CAS then follow this step

1. Go to NLB Manager Cluster Properties in Clusters

Parameters Tab and write down the Network address for

the NLB Cluster.

2. Shut down the NLB Cluster VMs one by one then in Hyper-V Manager, manually configure the Network Adapters that you added to the VMs for the NLB Cluster

to use a Static MAC Address that matches the NLB

Network Address: 02-BF-C0-A8-01-03.

3. Check the checkbox “Enable Spoofing of MAC Addresses”

4. Restart the CAS Server VMs in Hyper-V Manager. 5. Confirm successful NLB Cluster convergence status one

more time.

NIC FORWARDING

Run the below command on both the Servers so that NLB NIC can forward service request to Production NIC

This is a VERY IMPORTANT STEP, if you have missed this then NLB

will not be able to forward the CAS request to Production NIC and

no app will open.

1. Open the cmd prompt with Run as Administrator and run the below cmd.

netsh interface ipv4 set interface “NLBInterfaceLabel” forwarding=enabled