When is the ‘CP/Flow session table full’ alarm triggered?

This article provides information about the event that triggers the CP/Flow session table full alarm on SRX devices.

There can be two scenarios.
1. when my total cp session capacity is higher than the total of max flow session capacity of all SPUs.
Example: In SRX 3600 without extreme license we will have around 2.3 Mil Cp session capacity, In the same box if we use just 2 SPU, the total of max flow session of both SPU will account to around 1.5 Mil session capacity.

2. When my total cp session capacity is lower than the total of max flow session capacity of all SPUs.
Example: In SRX 3600 without extreme license we will have around 2.3 Mil Cp session capacity, In the same box if we use just 4 SPU, the total of max flow session of both SPU will account to around 3.5 Mil session capacity.

In case 1: when my total cp session capacity is higher than the total of max flow session capacity of all SPUs.
When the session table of the flow SPU is full, the failed-sessions counter increases, if new sessions are created on this SPU:

In Case 2: When my total cp session capacity is lower than the total of max flow session capacity of all SPUs.

However, it is rare that the following alarm is simultaneously generated in syslog:

This alarm is generated, when the CP current session is greater than the sum of the max flow sessions of all SPUs. The alarm is cleared, when the CP current is less than or equal to the sum of the max flow sessions of all of the SPUs.

To obtain the current number of CP sessions, use either of the following commands:

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Prasanna

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