Hello,
We have a problem with our VPN.
We are experiencing an issue that occurs once every month, where employees (it changes - skipping between users) using only Mac computers come to the office (but happens also in their home wifi) and are unable to access internet when they are connected to VPN.
We use:
Forticlient vpn only free - last version
IPSEC VPN
When they try to ping servers/addresses: sendto no buffer space available
When it happens I see many interfaces with addresses of VPN (192.168.11.0/24).
After disabling interface with VPN: ifconfig interface utun4 down - internet works!
Another user told me: WIFI works, VPN works. He leaves the computer, computer goes to sleep mode and after that Forticlient seems as connected but no internet!
Another user reported: I was on the train, using HOTSPOT and Forticlient.
Close the lid (So internet was disconnected). Went to the Office, I was connected to Office's WIFI and had this problem of buffering.
Why are there many interfaces instead of just one? Why does FortiClient create multiple connections?
Thanks
Hi Captain
Here we can see IPv6 default gateways are being injected.
Internet6:
Destination Gateway Flags Netif Expire
default fe80::%utun0 UGcIg utun0
default fe80::%utun1 UGcIg utun1
default fe80::%utun2 UGcIg utun2
default fe80::%utun3 UGcIg utun3
default fe80::%utun4 UGcIg utun4
default fe80::%utun5 UGcIg utun5
In case you are not using IPv6, can you just try disable it on your MacOS and try again?
Or check on FG side if IPv6 split tunnel is disable, then enable it.
Or just disable IPv6 on FG's IPsec config.
You can also remove the IPv6 default gateway through to confirm this is the actual root cause.
Again the idea is to avoid having default gateway through tunnel in your routing table.
Hello,
Attaching the configuration of IPv6 in my IPSEC (from Fortigate)
Should I disable something?
Could you please kindly explain why it might create a problem
Thanks
On the IPsec config I see IPv6 is disabled on FG. That's strange because it seems something else is pushing IPv6 default gateway on the client.
Next step is, when the issue occurs, delete the IPv6 gateways on the client that are through the VPN tunnels, and see if it fixes the issue.
A command that already tested and fix the problem is:
ps aux | grep -i 'forti' | grep -v 'grep' | awk '{print $2}' | xargs sudo kill -9
Kill all the processes of Forticlient
But if I asked users to do it, they would hate me because they just want the problem solved.
As you may know some issues need long troubleshooting, and it can take long time especially when there is no direct interaction with the machine.
In this case I don't have immediate solution. For this I hope some more experienced member can help better.
Works for me. Thank you very much for this solution.
Hello,
Same issue... not solved.
Attaching log from Forticlient from mac computer with multiple interfaces:
Hello,
I see in my logs of Forticlient (I use ipsec)=
message_handler:469 send pfkey errno: 1
Any idea please?
User has full permissions
We tried: Reinstall other old Forticlient versions
Thanks
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