GVPN Client cannot connect on ATT network

MikeBMiller

This morning I tried to set up a Sonicwall Global VPN client at a residence. I have done this many times with few problems. So I installed the client software and tried to initiate a connection. It never even gets to the screen where it asks for the shared secret. If I look at the log, it says the peer is not responding. So I tried using the same laptop to connect to several other of my customers that have SW VPNs. No luck on any of those either. Then I got my own laptop and connected to his home wifi and tried to connect to several of those VPNs with no luck. It was time for lunch, so I took the guy's laptop to lunch with me and tested it at a place with free wifi. Bingo - it connected perfectly,

So does anyone know of some setting on the AT&T network that would prevent the GVPN client from working correctly? We tried calling ATT, and got some clueless guy on the phone and then the call got cut off before any answer was received. This guy has ATT fiber to his house and was using the wifi that comes with the ATT modem.

I have ATT fiber at my house and the GVPN client works just fine here.

MitatOnge

I have faced like this. could you send gvc logs.

I think problem is ISAKMP packet.

https://www.sonicwall.com/support/knowledge-base/the-peer-is-not-responding-to-phase-1-isakmp-requests-error-in-global-vpn-client-gvc/170505733549058/

MikeBMiller

Thanks I will check that on Monday.

Ajishlal

@MikeBMiller

Seems its blocking by the either ISP or their modem.

Try to login their modem and enable the IPSEC & VPN related ports.

If it's not found, do the port forwarding in the modem;

https://www.att.com/support/article/u-verse-high-speed-internet/KM1123072

open the below listed ports;

Port 50 (UDP/ESP)

Port 500 (TCP)

Port 4500 (TCP)