Extra Shared Memory

This section discusses the amount of extra shared memory required and the steps to configure extra shared memory.

In Avi Load Balancer, there are various features that rely on database lookups. These features include IP reputation, L7 features dependent on a geographic database lookup, Bot Management, and GSLB site selection based on geolocation. These features need extra shared memory on the Service Engine to accommodate the requirements of these databases. Similarly, GSLB, where many configuration objects are involved, requires some extra shared memory on the Service Engine.

Extra Shared Memory Requirements

The requirements for extra shared configuration memory depend on the features being used.

The extra memory requirement for each feature is shown below:

Feature	Extra Shared Memory Required
IP reputation	40 MB
L7 features using GeoDB lookup	350 MB
Bot Management	600 MB (390 MB (=40 MB + 350 MB) for IP reputation and L7 GeoDB lookup)
GSLB using Geolocation	2000 MB
GSLB using any LB algorithm with 500-5000 GSLB Services	1000 MB
GSLB using any LB algorithm with greater than 5000 GSLB Services	2000 MB
CSRF Protection	500 MB

If you are using more than one of these features simultaneously, then configure extra_shared_config_memory to be the sum of the requirements outlined above. However, as the Bot Management feature relies upon IP Reputation and L7 GeoDB lookup, the memory requirement of 600 MB already incorporates the 390 MB required for these two features.

Use the following examples to understand this further.

Example 1

Using Bot Management and GSLB Geo Location with 1000 GSLB Services.

The breakup of extra shared memory to be configured is as follows:

Feature	Extra Shared Memory Required
Bot Management	600 MB
GSLB using Geolocation	2000 MB
GSLB using load balancing algorithm with 1000 services	1000 MB
Total shared Memory to be configured	600 + 2000 + 1000 = 3600 MB

Example 2

Using Bot Management, IP reputation, and GSLB Geo Location with lesser than 500 GSLB Services.

The breakup of extra shared memory to be configured is as follows:

Feature	Extra Shared Memory Required
Bot Management	600 MB
IP reputation and GSLB Geo Location with <500 GSLB Services	2000 MB Note: IP reputation requires 40 MB additional shared memory. Since this 40 MB is accounted for under Bot management, it can be excluded from the extra shared memory configuration. Therefore, only the shared memory of 2000 MB , required for GSLB geo- location is considered here.
Total shared Memory to be configured	600 + 2000 = 2600 MB