Nortel Networks WEB OS 212777 - Manual (Page 141)

Web OS 10.0 Application Guide
Chapter 6: Server Load Balancing n 141
212777-A, February 2002
Load Balancing Metric
For each service, a real server is selected using the configured load balancing metric ( hash ,
leastconns , minmisses , or roundrobin ). To ensure even distribution, once an avail-
able server is selected, the switch will use the roundrobin metric to choose a real port to
receive the incoming connection.
If the algorithm is leastconns , the switch sends the incoming connections to the logical
real server (real server IP address/port combination) with the least number of connections.
The /cfg/slb/virt command defines the real server TCP or UDP port assigned to a ser-
vice. By default, this is the same as the virtual port (service virtual port). If rport is config-
ured to be different from the virtual port defined in /cfg/slb/virt < virtual server
number >/service <virtual port>, the switch maps the virtual port to the real port.
N OTE – To use the single virtual port to multiple rport feature, configure this real server port
option to be a value of 0. However, note that you cannot configure multiple services with mul-
tiple
rports in the same server if the multiple rport feature is enabled.
Configuring Multiple Service Ports
Two commands, addport and remport , under the real server menu allow users to add or
remove multiple service ports associated with a particular server. (A service port is a TCP or
UDP port number.) For example:
addport 8001 and remport 8001.
1. Configure the real servers.
2. Add all four servers to a group.
3. Configure a virtual server IP address.
>> # /cfg/slb/real 1/rip 192.168.2.1/ena
>> # ../real 2/rip 192.168.2.2/ena
>> # ../real 3/rip 192.168.2.3/ena
>> # ../real 4/rip 192.168.2.4/ena
>> # /cfg/slb/group 1
>> Real server Group 1# add 1
>> Real server Group 1# add 2
>> Real server Group 1# add 3
>> Real server Group 1# add 4
>> # /cfg/slb/virt 1/vip 192.168.2.100/ena