Configuring congestion control using the CLI

Use the CLI commands in this procedure to configure analysis congestion control. You can configure the Congestion Bypass option, the Connection Refusal option, or both.

Prerequisites

An established connection between the appliance and the Internet.
You are logged in to the appliance CLI as an Admin or Operator.

To configure the Congestion Bypass and Connection Refusal congestion control options:

Go to CLI configuration mode.

hostname > enable
hostname # configure terminal

View the current configuration for the analysis congestion control options. Check the values displayed in the following lines in the command output:

"Congestion Bypass Mode:"
"Congestion Bypass Threshold:"
"Congestion Refuse-connnection Mode:"
"Congestion High Threshold:"

In the following example, the Congestion Bypass option and the Connection Refusal options are configured with default values:

hostname (config) # show email-analysis policy 
  Email-Analysis Policy:
    Analyze URLs in body:      yes
	Analyze attachments:          yes
	Analyze email using YARA:     yes
	Email YARA Weight Cap:        30
	Max Email Size (MB):          35
	Analysis Timeout (sec):       240
	Analyze image URLs:           yes
	Advanced URL Defense:         no
       Extract/Rewrite HTML URL as Text:    yes
	Max URLs Analyzed/email:      5
	Max Att. Analyzed/email:      20
	Congestion Bypass Mode:   yes
	Congestion Bypass Threshold:   2000
       Congestion Bypass Unprocessed Limit:  0
       Congestion Refuse-connection Mode:   yes
	Congestion High Threshold:    10000
	Congestion Low Threshold:     9000
	.
	.
	.

By default, both options are enabled. The Congestion Bypass Threshold is 2000 emails and URLs queued, and the Connection Refusal threshold is 10,000 emails queued.

(Optional) Modify the Analysis Bypass configuration.
To disable Analysis Bypass:
hostname (config) # no email-analysis policy congestion mode bypass enable
To change the Analysis Bypass threshold:
hostname (config) # email-analysis policy congestion bypass-threshold 19000
To enable Analysis Bypass:
hostname (config) # email-analysis policy congestion mode bypass enable
(Optional) Modify the Connection Refusal configuration.
To disable Analysis Bypass:
hostname (config) # no email-analysis policy congestion mode refuse-connection enable
To change the Analysis Bypass threshold:
hostname (config) # email-analysis policy congestion high-threshold 19000
To enable Analysis Bypass:
hostname (config) # email-analysis policy congestion mode refuse-connection enable

Verify your configuration.

hostname (config) # show email-analysis policy
  Email Analysis Policy:
    Analyze URLs in body:      yes
    Analyze attachments:          yes
    Analyze email using YARA:     yes
    Email YARA Weight Cap:        30
    Max Email Size (MB):          35
    Analysis Timeout (sec):       240
    Analyze image URLs:           yes
    Advanced URL Defense:         no
    Extract/Rewrite HTML URL as Text:    yes
    Max URLs Analyzed/email:      5
    Max Att. Analyzed/email:      20
    Congestion Bypass Mode:   yes
    Congestion Bypass Threshold:   19000
    Congestion Refuse-connnection Mode:   yes
    Congestion High Threshold:    29000
    Congestion Low Threshold:     26100
    .
    .
    .

Save your changes.
```
hostname (config) # write memory
```