Modbus
Cellular
Gateway
Index
skipping
is
used
to
reserve
slots
for
new
function
insertion,
when
required.
278
Following
tables
list
the
parameter
configuration
as
a
group
example
for
the
gateways
in
above
diagram
with
"VRRP"
enabling.
Use
default
value
for
those
parameters
that
are
not
mentioned
in
the
tables.
Master
Gateway
Configuration
Path
[Ethernet
LAN]
‐
[Configuration]
([Basic
Network]
‐
[LAN&VLAN])
LAN
IP
Address
10.0.75.1
Subnet
Mask
255.255.255.0
(/24)
Configuration
Path
[VRRP]
‐
[Configuration]
VRRP
■
Enable
Virtual
Server
ID
253
Priority
of
Virtual
Server
254
Virtual
Server
IP
Address
10.0.75.200
Backup
Gateway
Configuration
Path
[Ethernet
LAN]
‐
[Configuration]
([Basic
Network]
‐
[LAN&VLAN])
LAN
IP
Address
10.0.75.2
Subnet
Mask
255.255.255.0
(/24)
Configuration
Path
[VRRP]
‐
[Configuration]
VRRP
■
Enable
Virtual
Server
ID
253
Priority
of
Virtual
Server
253
Virtual
Server
IP
Address
10.0.75.200
Scenario
Operation
Procedure
In
above
diagram,
the
Master
Gateway
and
the
Backup
Gateway
are
the
redundant
gateway
group
of
Network
‐
A
and
the
subnet
of
its
Intranet
is
10.0.75.0/24.
The
master
gateway
has
the
IP
address
of
10.0.75.1
for
LAN
interface,
203.95.80.22
for
WAN
‐
1
interface.
However,
the
backup
gateway
has
the
IP
address
of
10.0.75.2
for
LAN
interface,
118.18.81.33
for
WAN
‐
1
interface.
They
both
serve
as
NAT
routers.
Specify
the
ID
of
VRRP
virtual
server
to
be
"253"
and
its
IP
address
to
be
"10.0.75.200".
The
priority
of
the
master
gateway
is
254
and
it
is
larger
than
the
one
(253)
of
the
backup
gateway.
At
first
stage,
all
data
from
the
Intranet
go
through
the
master
gateway
that
has
the
highest
priority.
Once
the
master
Internet
connection
is
broken,
the
backup
gateway
will
take
over
the
data
transmitting
job
and
serve
as
the
master
gateway.
When
a
gateway
with
higher
priority
than
current
master
gateway
recovers
from
its
broken
Internet
connection,
it
will
be
in
charge
of
the
data
transmitting
again.
