User guide

17-28 E
XTREME
W
ARE
S
OFTWARE
U
SER
G
UIDE
S
ERVER
L
OAD
B
ALANCING
(SLB)
The switches in a redundant SLB configuration should have identical SLB
configurations except for the failover parameters. You can configure SLB on one switch,
upload the configuration, edit it, and download it to the second switch to replicate the
configuration.
U
SING
P
ING
-C
HECK
Failover ping-check is used to determine if the currently active SLB server has the
required network connectivity. If the specified IP address is unreachable for a specified
duration, the ping-check triggers a failover to the redundant switch.
To configure ping-check, use the following commands:
config slb failover ping-check <ipaddress>
enable slb failover ping-check
The address being pinged should be that of a device other than the redundant
SLB switch.
C
ONFIGURING
A
CTIVE
-A
CTIVE
O
PERATION
Using active-active redundant SLB, you configure one switch as unit 1 and the other
switch as unit 2. You then assign the VIPs either to unit 1 or to unit 2 (by default, a VIP
is assigned to unit 1). When both switches are active, each switch performs SLB only for
the VIPs assigned to it. If a switch fails, the other switch takes over the VIPs assigned to
the failed switch.
The basic failover configure command assigns the switch's unit number:
config slb failover unit [1 | 2] remote-ip <ipaddress> local-ip
<ipaddress>:<L4Port> {alive-frequency <seconds> timeout <seconds>}
{dead-frequency <seconds>}
Where the following is true:
•
remote-ip
— Specifies the IP address of the redundant SLB switch.
•
local-ip
— Specifies the IP address of the switch you are configuring.
All VIPs with a given virtual IP address must be assigned to the same unit.