HP network adapter teaming: load balancingin ProLiant servers running Microsoft Windows operating systemswhite paperIntroduction. 2Overview of teaming and load balancing. 2Transmit Load Balancing. 3Configuring TLB . 3Receive Load Balancing. 4Receive Load Balancing configuration decisions . 4Configuring Receive Load Balancing . 5Conclusion. 6For more information. 6
IntroductionBalancing the network traffic load on a server can enhance the functionality of the server and thenetwork. Load balancing within network interconnect controller (NIC) teams enables distributing trafficamongst the members of a NIC team so that traffic is routed among all available paths. HP NetworkConfiguration Utility (NCU) software provides a user-friendly method to configure load balancing andto view load-balancing statistics. Load balancing is available to all NCU customers who team theirNICs in ProLiant servers running Microsoft Windows operating systems.This paper describes the load balancing options available with HP network adapter teaming, which isavailable on NICs in slots or embedded on ProLiant servers.Overview of teaming and load balancingBy means of HP teaming software, system administrators can configure the network adapter portswithin a ProLiant server as teams to provide fault tolerance. A team consists of two to eight ports thatfunction as if they were a single port. The virtual port appears to the system as a single physicaladdress and a single IP address. One port in the team, designated as the primary port, transmits andreceives all traffic. The other ports are designated as backup ports. Should the primary portexperience a disabling problem such as hardware failure, link loss, or a blocked path, HP teamingsoftware will automatically make one of the backup ports the primary port.Besides providing fault tolerance, NIC teams can also share the load of network traffic whilepresenting the unified single address to other network resources. This sharing of the load is calledload balancing. The ports in a team can share both traffic transmitted by the server and trafficreceived by the server.
Transmit Load BalancingThe purpose of transmit load balancing (TLB) is to distribute transmitted traffic equally across all portsin the team. TLB allows a ProLiant server, statistically and heuristically, to balance network traffic morefully across all team members. Several configuration options allow administrators to determine whichport will handle the transmit traffic. Table 1 identifies configuration options available for teamsproviding TLB with fault tolerance.Table 1. Configuration options for transmit load balancing with fault tolerance in ProLiant serversMethodDefinitionUsage notesAutomatic(the default andrecommendedmethod)Allows the software to determine (statistically and heuristically) thebest load balancing possible, dynamically and flexibly, based onper-packet packet type. A combination of Destination IP and TCPconnection is used.Destination MACaddressSends traffic through a port based on the physical address (MAC)of the destination node. Uses the least significant three bits tomap to the transmission port.Do not use a router in thistraffic path.Destination IPaddressSends traffic through a port based on the IP address of thedestination node. Uses the least significant three bits of the rightmost octet to map to the transmission port.This is typically the easiestand most useful configuration.TCP connectionSends traffic through a port based on the network connectionpath (source-IP address, source port, destination-IP address,destination Port). Uses elements of all four address fields to mapto the transmission port.This is used fairly often andcan help on multi-applicationservers.Round robin(packet order notguaranteed)Sends traffic through a port based on a sequential selectionmodel, which does not guarantee “in order” packet delivery onone path.Web server environments arethe most appropriatecandidates for this option.The default; most commonlyused option.UDP-based applications arealso good candidates.Configuring TLBOnce you have decided on the type of transmit load balancing for your system, use the NetworkConfiguration Utility (NCU) to configure your choices. The NCU interface provides a simpleconfiguration panel for specifying how traffic will be routed through the ports in a team (Figure 1).To configure TLB, complete these steps:Open the HP Network Configuration Utility.Display the properties for the network adapter team.In the Team Properties window, select the Teaming Controls tab.Enter the appropriate team name.From the Team Type drop-down list, select the desired type of TLB team.From the Transmit Load Balancing Options drop-down list, select the TLB configuration option ofyour choice.7. Click OK.220.127.116.11.5.6.
Figure 1. Using the HP Network Configuration Utility to configure TLB for a NIC teamReceive Load BalancingSwitch-assisted load balancing (SLB) balances traffic transmitted and received by a ProLiant server.SLB is accomplished by means of several switch ports grouped into a single virtual port. The virtualswitch selects the adapter to receive traffic based on the particular method supported by the switch.Receive Load Balancing configuration decisionsMultiple configuration options allow administrators to determine how the ports will handle traffic.Table 2 identifies configuration options available for teams providing SLB.Table 2. Configuration options for receive load balancing in ProLiant serversMethodDefinitionTeams neededWhen to use802.3ad Dynamic withFault Tolerance or LACP(no license required)Using two virtual ports, theswitch selects the ports forreceive traffic as needed.At least onetwo-port teamPorts are limitedSwitch-assistedDual ChannelLoad Balancing(requires PEINP license)The switch uses two or morestatic ports, each designatedto handle either transmit orreceive traffic.At least onefour-port teamwith two ports perport channelTraffic is normally not high.The switch supports this method.Ports are numerous.Traffic is constantly high.The switch supports this method.Switch redundancy is required.
Configuring Receive Load BalancingOnce you have decided on the type of switch-assisted load balancing for your system, use the HPNCU to configure your choices. The NCU interface provides a simple configuration panel forspecifying how traffic will be routed through the ports in a team.To configure SLB, complete these steps:Open the HP Network Configuration Utility.Display the properties for the network adapter team (Figure 2).In the Team Properties window, select the Teaming Controls tab.Enter the appropriate team name.From the Team Type drop-down list, select the desired type of SLB team: Dynamic 802.3ad if youdo not have a PEINP license, Dual Channel if you have a license or both if you have a license andwant to use Dynamic Dual Channel teaming.6. From the Transmit Load Balancing Options drop-down list, select the TLB configuration option ofyour choice.7. Click OK.18.104.22.168.5.Figure 2. Using the HP Network Configuration Utility to configure SLB Transmit and Receive Load Balancing in a ProLiant server
ConclusionLoad balancing is an important way to maximize network efficiency. HP provides practical andeffective load balancing options and smooth configuration for harnessing the power of networks thatcontain ProLiant servers.For more informationFor more information about ProLiant network adapters and adapter teaming, see the following /products/servers/networking/teaming.html#1 2005 Hewlett-Packard Development Company, L.P. The information containedherein is subject to change without notice. The only warranties for HP products andservices are set forth in the express warranty statements accompanying suchproducts and services. Nothing herein should be construed as constituting anadditional warranty. HP shall not be liable for technical or editorial errors oromissions contained herein.Microsoft and Windows are U.S. registered trademarks of Microsoft Corporation.TC050104WP/2005
network. Load balancing within network interconnect controller (NIC) teams enables distributing traffic amongst the members of a NIC team so that traffic is routed among all available paths. HP Network Configuration Utility (NCU) software provides a user-friendly method to configure load balancing and to view load-balancing statistics.