Description
This article describes how to calculate 'Authentication Refresh' count-down number which shows under the Authentication Keep-alive page of FortiGate.
Scope
FortiGate.
Solution
To understand where the 'Authentication Refresh' count-down number comes from and know how to calculate it to display as requested.
Make sure that the authentication keep-alive page is enabled.
How to check if the authentication keep-alive page is enabled/disable
With the following CLI commands:
# config system global
set auth-keepalive enable <----- Disable by default (set as enable for enabling authentication keep-alive page)
end
FortiGate with VDOM enabled:
# config global
# config system global
set auth-keepalive enable <----- Disable by default (set as enable for enabling authentication keep-alive page)
end
For Checking/setting Authentication timeout using GUI:
a) For FortiGate without VDOM enabled:
Go to User & Device ( User&Authentication ) -> Authentication Settings -> Authentication Settings -> Authentication timeout :Z minutes.(Z is the value of Authentication timeout.).
b) For FortiGate with VDOM enabled:
Choose the VDOM to configure -> User&Device ( User&Authentication ) -> Authentication Settings -> Authentication Settings -> Authentication timeout : Z minutes.(Z is the value of Authentication timeout.).
For Checking/setting Authentication timeout using CLI:
a) FortiGate without VDOM enabled:
#config user setting
set auth-timeout 23 ---> Enter an integer value from <1> to <1440> (default = <5> in minutes)
end
b) FortiGATE with VDOM enabled:
#config vdom
edit <vdom Name>
config user setting
set auth-timeout 23 23 ---> Enter an integer value from <1> to <1440> (default = <5> in minutes)
end
end
How to calculate Authentication Refresh time as shown below snapshot A
Formula for authentication Refresh count-down number = Z x 20
For example:
Authentication timeout : 23 minutes.
Z = 23
So At 'Authentication Keep-alive' page -> 'Authentication Refresh count-down number
It will show = Z x 20 = 23 x 20 = 460 seconds to count down.
Authentication timeout : 23 minutes.
Z = 23
So At 'Authentication Keep-alive' page -> 'Authentication Refresh count-down number
It will show = Z x 20 = 23 x 20 = 460 seconds to count down.
Figure : Snapshot A
Reference Documents :
https://docs.fortinet.com/document/fortigate/6.4.4/cli-reference/508620/config-user-setting
Technical Tip: Authentication keep-alive page
https://community.fortinet.com/t5/FortiGate/Technical-Tip-Authentication-keepalive-page/ta-p/196620
Technical Tip: Explanation of auth-timeout types for Firewall authentication users
