IPSec VPN not connecting on Android phone.

[dareios]

Hello!

I have recently signed up to a new mobile contract and trying to configure my Android phone to connect to a VPN using IPSec PSK VPN and the connection is not going through. I do not even see the connection attempt in my router logs. I spoke to support over TOBi assistant and they have verified SecureNet is disabled and no content blocking bars are in place and assured me this would fix the problem. I have restarted the device as instructed and still my VPN is not establishing a connection.

Please help.

[CrimsonLiar]

Your connection is probably using CGNAT (Carrier Grade Network Address Translation).  The problem is that CGNAT does not always play nicely with IPSec VPNs!  If you have the option, using WireGuard may perform better, but even that is not guaranteed to work over CGNAT.

See: https://www.anandtech.com/show/18692/the-ubiquiti-diaries-a-sitetosite-vpn-story/3 for a bit more info

[Bhavesh1]

You have taken the necessary steps to troubleshoot the VPN connection issue, but it's still not working. To further diagnose the problem, I suggest checking if your Android phone's IPSec PSK VPN settings are correctly configured. Double-check the VPN server address, your pre-shared key, and authentication settings. If everything appears correct and the issue persists, consider trying a different VPN server or contacting your VPN service provider for additional support.
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