Here has not LInux Anyconnect client download in the email when Sandbox is ready to connect.
Download the Cisco AnyConnect VPN Client Software
after I installed a 3rd party anyconnect client, I was not able to connect the Lab LINKprovided
devnetsandbox-us-sjc.cisco.com:20248
by using IP address was same error
128.107.93.228:20248:
by using openconnection , the connection was refused
(py3-venv) devnet@devnet-virtual-machine:~/dnav3-code$ openconnect -b https://devnetsandbox-us-sjc.cisco.com:20248
POST https://devnetsandbox-us-sjc.cisco.com:20248/
Failed to connect to 128.107.93.228:20248: Connection refused
Failed to connect to host devnetsandbox-us-sjc.cisco.com
Failed to open HTTPS connection to devnetsandbox-us-sjc.cisco.com
Failed to obtain WebVPN cookie
internet connection was verified and good.