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New Contributor

100D locks up on firmware version 5.4.0

I have several 100D's and 90D's in my environment. One unit in particular (100D) is locking up every 2 hours. The errors I get are

FortiGate has reached system file descriptor limit for 1 seconds, the error in the FAZ is Kernel enters conserve mode.  The unit rebooted after a firmware update and stated it was not rebooted properly (odd). I am thinking of going up a version to 5.4.2 tonight. I have AV disabled, but not IPS.  anyone see this behavior yet?


I've seen conserve mode on various versions of firmware before.


Why not go to the latest version of 5.4.*?



New Contributor

I am planning on going to the latest versions tonight


Make sure you follow their prescribed path to get to 5.4.8 - looks like there's quite a lot of upgrades to happen.


If you still see conserve mode after this, a ticket to TAC can help.


I've seen various causes of this over the years, sometimes IPS engine, sometimes other things.


TAC can definitely help.




You need to re-format the boot drive and reload the image of the 5.4.x version then reload the saved config. That's what TAC would instruct when you open a TT. If I member correctly, at least 5.4.0 and 5.4.1 had either or both boot drive and log disk when it's upgraded from 5.2.x. It should have been described in the release notes. That's why we skipped those versions when we upgraded ours. Read the release-notes carefully and follow the instructions.


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