Huawei quidway s7700 Configuration Manual page 265

Quidway S7700 Smart Routing Switch
Configuration Guide - SPU
By default, the probe mode is fail-on-one. In fail-on-one mode, a server is considered as Down
when all the probes bound to the server group detect that the server member is in Down state.
When the probe mode is fail-on-one, the server member is considered as Down when a probe
bound to the server group detects that the server member is in Down state.
Step 5 Run:
failaction { purge | reassign }
The action performed when a server fails is set.
By default, no action is taken when a server fails.
If the action is set to purge, when the master server fails, the connections of the master server
are removed and not switched to a backup server. If the action is set to reassign, when the master
server fails, all the connections of the master server are switched to a backup server.
Step 6 Run:
switch-threshold percent1 restore-threshold percent2
The threshold for switching services from the master server to the backup server is set.
percent1 specifies the threshold for the master server group to remain active and percent2
specifies the threshold for the backup server group to remain active. When the percentage of
active servers in the master server group is smaller than or equal to the value of percent1, the
SPU switches services to the backup server group. When the percentage of active servers in the
master server group is greater than the value of percent2, the master server group is recovered
and starts to provide services.
By default, the thresholds for the master and backup server groups to remain active are 0. In this
case, if all the servers in the master server group are invalid, the SPU automatically switches
services to the backup server group. If a server in the master server group becomes active, the
SPU switches services back to the master server group.
Step 7 Run:
forward-mode dnat
The packet forwarding mode is set to DNAT.
Or, run
forward-mode dmac
The packet forwarding mode is set to DMAC.
In server load balancing, the packet forwarding mode can be set to DNAT or DMAC. In DNAT
mode, the SPU changes the destination IP address of packets to the IP address of a server before
forwarding them. In DMAC mode, the SPU changes the destination MAC address of packets to
the MAC address of a server before forwarding them. The destination IP address of the packets,
however, remains unchanged.
Step 8 Run:
load-balance method { { hash address { destination | source | both } [ netmask ] }
| { hash url [ begin-pattern expression1 ] [ end-pattern expression2 ] } |
leastconns | roundrobin }
The load balancing algorithm is set.
By default, the WRR algorithm is used for load balancing.
Issue 01 (2011-07-15) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
6 Load Balancing Configuration
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