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New Contributor

What FortiOS to choose? 4.3, 5.0 or 5.2?

I have several FortiGate 80c and they are all at 4.3.15.   I remember few years ago when 5.0 was first released, it suffered performance issue and that's why I stick to 4.3.   However, I think there's a bug related to VPN in 4.3.15.  Unfortunately, 4.3 is no longer supported by FortiNet so I think I might need to jump to version 5.  So let me ask this stupid question:   Is there a general consensus about performance in 5.0 and 5.2?  I've seen some recent posts about 5.2 -- it might be a better idea to stick to version 5.0, right?  Is there a version that most people would agree on its quality as very stable?   Thanks in advance.

Esteemed Contributor II

I'm not sure about performance for 5.0 and 5.2. But we suffered some memory leak issues while most of our FWs are running 5.0.x, as well as the last SSL bug. Since 5.4 is out for last 7 month, the support on 5.0.x would be numbered by now. I would suggest you step your unit(s) up to 5.2. 



I agree with Toshi. 5.2 is the most stable version of fortiOS right now. We have about 50 Firewalls with this version and everything is working fine for now.

Hope it helps.




Thanks to Toshi and lescudero for your precious feedback.


OK, I will avoid 5.0 at all cost!


Valued Contributor

Yeah, roll with 5.2.x for now. I have moved all clients to 5.4.1 and haven't noticed any issues yet so I am slowly coming around to recommending everyone do the same there as well haha