User guide

E
XTREME
W
ARE
S
OFTWARE
U
SER
G
UIDE
17-5
F
ORWARDING
M
ODES
F
ORWARDING
M
ODES
The switch supports the following SLB forwarding modes:
• Tran sp arent
• Tran sl at io na l
• Port Translation
• GoGo
Table 17-1 summarizes the features supported by each forwarding mode.
T
RANSPARENT
M
ODE
Using transparent mode, the switch does not modify the IP addresses before sending
the traffic on to the selected server. To accomplish this all servers must respond to the IP
addresses associated with the virtual server. This virtual IP address is the address used
by the clients to connect to the virtual server. The servers must have this address
installed as a loopback address and have the address associated with the virtual server
to be load balanced. As with any server load balancing application, the content must be
duplicated on all physical servers.
In transparent mode, servers can be directly attached or have an L2 switch between the
SLB switch and the server. It is not possible to have a router between the SLB switch
and the servers being balanced.
Table 17-1: Forwarding Mode Feature Summary
Transparent Translational Port Translation GoGo
Performance Hardware-based,
server-to-client
CPU-based,
bi-directional
CPU-based,
bi-directional
Hardware-based,
bi-directional
Load sharing
algorithms
Round-robin,
Ratio, Priority,
Least Connections
Round-robin,
Ratio, Priority,
Least Connections
Round-robin,
Ratio, Priority,
Least Connections
Round-robin
(hash)
Persistence IPSA + Mask, IP
list
IPSA + Mask, IP
list
IPSA + Mask, IP
list
IPSA
Health
checking
L3, L4, L7,
External
L3, L4, L7,
External
L3, L4, L7,
External
L1