Poor data throughput using FortiClient on macOS

[JonSnow]

I can't get more than 1mbps bandwidth up and slightly less down, when connected to the Fortigate60 via FortiClient on my Mac, using SSL VPN. I have had this problem for a very long time and I have tried with many different Forticlient  and macOS versions. I have the latest official firmware on the FG60 as well as 5.4.1 FortiClient on the Mac.

I can also run Windows on my Mac (via Boot camp) and when using Forticlient there, I get about 25 mbps throughput (up). This means it is not network related, but either a problem related to macOS, Forticlient for Mac or any other software running on the mac

I have removed all other firewall or antivirus software to limit interferences. The Mac Firewall is on, but that seems to make no difference as I've also tried it turned off. I use standard Network settings (Ethernet/MTU 1500/Full Duplex flow-control)

Since it works flawlessly on the same hardware, using Windows10, but I get only 4% the throughput using the macOS, it wonder if it is some odd network setting in my macOS that causes this. 

I've also tried with a colleagues mac and get the same poor throughput. 

Has anyone succeeded with SSL VPN from Mac? Can anyone help with ideas what it could be and how it could be resolved? What have I missed? 

Thanks

[moby]

Hi Jon,

Whilst I do not know the root cause for this problem  - we also had this problem  - we switched to IPSEC VPN and we had much better results with Macs.

Cheers, Moby