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johnlloyd_13
Explorer III
February 5, 2025
Solved

SNAT Policy Log Allowed in FGT VDOMs

  • February 5, 2025
  • 11 replies
  • 2013 views

hi,

i'll be creating multiple (a lot) SNAT policy in a multi-VDOM FGT which is an "F" series (1000 plus model)

my question, do i enable/allow log "all sessions" or just "security events"?

can my current platform (1000 plus F model) can handle such log?

i just want to prevent any high CPU/memory due to lots of NAT processing/cache.

image.png

 

Best answer by dingjerry_FTNT

Hi @johnlloyd_13 ,

 

Technically, it's hard to cause high CPU/Memory usage issues due to NAT usage.

 

1) The following doc is talking about possible reasons causing high CPU:

 

https://docs.fortinet.com/document/fortigate/7.6.2/administration-guide/232929/troubleshooting-high-cpu-usage

 

2) The KB is talking about something for conserve mode (Memory usage issue)

 

https://community.fortinet.com/t5/FortiGate/Technical-Tip-How-conserve-mode-is-triggered/ta-p/198580?externalID=FD33103

 

 

11 replies

funkylicious
SuperUser
SuperUser
February 5, 2025

https://community.fortinet.com/t5/FortiGate/Technical-Tip-Difference-between-Security-Events-and-All-session/ta-p/206881 

Since the 1000F does not have a local disk to store the logs, all logs will be held in memory for a rather short duration of time or until a reboot.

It would be recommended to use a external syslog server or FortiAnalyzer to send the logs to relieve the FGT from any 'stress' .

"jack of all trades, master of none"
dingjerry_FTNT
Staff
Staff
February 5, 2025

Not true. 

 

FGT 1001F does have a Local Disk. It should be the same for FGT 1000F.

 

Version: FortiGate-1001F v7.4.7,build2731,250120 (GA.M)
......
Log hard disk: Available

 

@johnlloyd_13 ,

 

It should be fine to enable NAT and logs in multiple policies.

funkylicious
SuperUser
SuperUser
February 5, 2025

as far as I know, only models ending with xxx1 have local storage, maybe on higher models/chassis this rule doesn't apply but in the product matrix 1000F is not listed with storage but rather, Local Storage 960 GB (1001F)

"jack of all trades, master of none"
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