Network Load Balancing with KCS SMTP-Based Links (MX7, SM, MFP, SC7)

Issue

Use of Microsoft Network Load Balancing clusters with SMTP-Based Links on KCS 9.x and above

• Setup of NLB-Cluster with one Link using only one Network-Interface.
• Setup of NLB-Cluster with 2 or more Links using different NICs (Network Interface Controller), one is using NLB, others do not use it.

Solution

Customer uses TC/Link-MX7 and TC/Link-SM without NLB because of alternative IP-Addresses inside the applications and TC/Link-MFP with NLB because most MFPs do not support multiple server-addresses.

Setup of the Network interfaces for only one NIC (with NLB) (Reference attached NLB-Setup PDF for screenshots)

• Step 1: Configure NIC-Card LAN-Properties Internet Protocol / IP Settings
  Add the Cluster IP Address to every server inside the NLB-cluster
  The Cluster IP Address must be higher then the dedicated addresses of every server
  The Cluster IP Address must be in the same subnet as the dedicated addresses
• Step 2: Configure NIC-Card LAN-Properties for Network Load Balancing (checkbox) on every server inside the NLB-cluster
• Step 3: Configure Load Balancing Properties / Cluster parameters
  Full Internet DNS-Name of the cluster
  Cluster operation mode: Multicast (not default)
• Step 4: Configure Load Balancing Properties / Host Parameters
  Different Host-Priority for every server
  Dedicated IP-Address for each server
• Step 5: Configure Load Balancing Properties / Port Rules
  Specify the Port-Range (default port for SMTP is 25)
  If you use more than one port you have to create more specific rules.
  It is not possible to use a rule with more than 1 port (e.g. 25 to 26) !!!
  Specify the protocol (default for SMTP is TCP)
  Filtering mode: multiple host, Affinity: none, Load weight: equal (checkbox)
• Step 6: Modify the Registry HKLM/Software/WOW6432Node/Topcall/TCLinkxx/TCLSM on every server
  OwnIPAddress: <Cluster IP-Address>
  NLBPortControl : 1

After starting TCSRV you can see in the KCS Monitor for the NLB-Link NLB port control running (Port: <port-number>).

Setup for all other Network interfaces with one ore more IP-Address on each NIC (without NLB)

• Configure the NICs without Network Load Balancing checked
• Define one or more IP-Addresses for every additional NIC
  It is possible to connect an additional NIC to the same physical network as the Cluster-NIC
  The IP-Address must be different (smaller or bigger than the Cluster-IP) and different to all other IP-Addresses

After starting TCSRV you can see in the KCS Monitor for the NLB-Links: NLB port control running (Port: <port-number>)
Non-NLB-Links: without the line above.

Level of Complexity 

High

Applies to  

References

13324_NLB-Setup.pdf

Keywords: SMTP, Network Load Balancing, Cluster, NLB