Installation guide
C HAPTER 12
Network Scenarios for Sensor High Availability
In the below use-case scenarios, the term Active/Passive refers to network topology and
not the Sensor High Availability (HA) configuration. In Sensor HA, both the Sensors are in
Active/Active state meaning both the Sensors will process traffic received on their
respective monitoring ports.
I-4010 Sensor in Load balanced Configuration
Scenario:
Two I-4010 Sensors are in load-balanced configuration. Each Sensor is monitoring an
active 1GB full duplex link - 500 Mbps in both directions- so each Sensor is handling
1Gbps of traffic. That is the total 2 Gbps throughput for each Sensor is utilized.
Will the total throughput that the Sensors need to handle is more, i.e. will the pair scan 4
Gbps of traffic when combined?
Solution:
When used in the High Availability mode, the total aggregate throughput of Sensor pair
remains the same as in the standalone mode. i.e., Total throughput capability of the pair
<= the quoted throughput rate of the single Sensor. This remains the same when the total
traffic is not evenly distributed across the Sensors.
For example, an I-4010 will scan for 2Gbps in standalone mode, as well as HA mode.
If X is the throughput of one Sensor and Y is the throughput of the second Sensor,
X +Y <= the quoted throughput rate of the Sensor model. Suppose X = 2Gbps and Y =
2Gbps, so the total is 4 Gbps, which exceeds the limit of the total throughput capability of
2Gbps that the pair can handle.
Both Sensors share all data they receive on their monitoring ports with their peers and,
most importantly, both Sensors process the data they receive from their peers. So when
you count how much data an individual Sensor in HA mode is seeing per second, you
have to include both the data it is receiving on its monitoring ports as well as the data it is
receiving from its peer via the HA / interconnect ports.
I-4010 Sensor in Active/Active HA mode
Scenario:
Suppose there are two I-4010's in active/active HA mode with 500Mbps of traffic in both
directions (full duplex), then how does the pair work?
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