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New Contributor

FortiOS 6.2: memory issues, best approach



I've been running 6.2 Beta and have switched to 6.2 public release, but the memory goes quickly up and system enters conserve mode and the system becomes unusable.


The 61E was running always around 75 to 80% for a couple of months, now with 6.2 the memory increased after an hour to that level and became useless.


What are your experiences and any best approaches with 6.2 troubleshooting (most probably the same as before) and feedback to Fortinet?

Contributor III

.0 releases of FortiOS are notorious for having bugs.  If this is a testing/lab firewall then go for it, but if you are using this in a production environment you are better off using a later 5.6.X or 6.0.X release for stability. 


For example at work we are still on a later variant of 5.6.X for a 500D supporting hundreds of users, while at home I have a FWF60E and I'm running 6.0.3.  I had some issues with DNS and 6.0.4 so I haven't gone past .3 yet.


We just grabbed a pair of 501s, and we will test 6.0.4 on those before we put into production with the assumption that the newer hardware on the 501Es will handle 6.0.X better.


I know it is tempting to get access to the latest gizmos, but on a FG of your size you are going to be constrained as to what you can do.  It may help to review the features enabled and turn off anything you are not using such as WLAN or Switch Control, Adv Routing, etc.


If you do open a ticket, you can SSH into the gate and capture some of the following:


diag debug crashlog read

(If that is insanely long, use "diag debug crashlog clear", wait 24 hours and send the new output)

If the UI is crashing and you can login, you may need to keep an open terminal session up via serial to capture the output, or enable Syslog.


Here is an article with more info:


for 5.4 but still useful.




You should follow/read this thread also:



Experienced the same thing with 2 customers - today.  It's the wad service using all the memory, device goes into conserve mode, then I get a call that the internet is down.


#diag sys top - find the wad service

#diag sys kill 11 wad-service-id

New Contributor III

Two 1500D's in HA A/P

WAD service creates memory creep.

Created an automation stitch to restart the WAD process daily at 3am.  Supposedly fixed in 6.2.1

Once restarted memory drops by 20%.


diagnose test application wad 99

New Contributor

Anyone know when the 6.2.1 will be release ?!

3 month with this bug, it is very annoying.

New Contributor

There's been an IPS memory leak bug that's still not resolved since FOS 5.4 :(

New Contributor

Having issues with internet going out after upgrading from 6.0.5 to 6.2 as well. Logged in to find it was in conserve mode due to memory usage. 

New Contributor III

Update to 6.2.1 will fix the memory issues....






New Contributor

Still seeing them in 6.2.1 on my 30E. Had to reboot this morning when no one could access the internet. Memory usage seems stable at 65% now, but was at 98% before the reboot. 6.2.1 has been installed for a couple of weeks or more.

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