DTLS handshake failed: Error in the push function. #122

~$ openconnect https://*.*.*.*:4443
POST https://*.*.*.*:4443/                                     
Connected to *.*.*.*:4443                     
SSL negotiation with *.*.*.*                                     
Server certificate verify failed: signer not found
                                                        
Certificate from VPN server "*.*.*.* failed verification.              
Reason: signer not found          
To trust this server in future, perhaps add this to your command line:
    --servercert sha256:***********
Enter 'yes' to accept, 'no' to abort; anything else to view: yes
Connected to HTTPS on *.*.*.*
XML POST enabled                                  
Please enter your username.                          
Username: ****                                                                                                                                                                                    [72/106]
POST https://*.*.*.*:4443/auth                                                                  
Please enter your password.                                         
Password:                                                              
POST https://*.*.*.*:4443/auth                   
Got CONNECT response: HTTP/1.1 200 CONNECTED                         
CSTP connected. DPD 90, Keepalive 32400                                                             
Connected as 10.20.30.14, using SSL + lz4                                                               
DTLS handshake failed: Error in the push function.                
(Is a firewall preventing you from sending UDP packets?)
DTLS handshake failed: Error in the push function.
(Is a firewall preventing you from sending UDP packets?)         
DTLS handshake failed: Error in the push function.  
(Is a firewall preventing you from sending UDP packets?)
DTLS handshake failed: Error in the push function.
(Is a firewall preventing you from sending UDP packets?)                        
SSL read error: The TLS connection was non-properly terminated.; reconnecting.
SSL negotiation with *.*.*.*                     
Server certificate verify failed: signer not found                       
Connected to HTTPS on *.*.*.*                                       
Got CONNECT response: HTTP/1.1 200 CONNECTED                                              
CSTP connected. DPD 90, Keepalive 32400                                                
DTLS handshake failed: Error in the push function.
(Is a firewall preventing you from sending UDP packets?)

~$ netstat -uanp
(Not all processes could be identified, non-owned process info
 will not be shown, you would have to be root to see it all.)
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
udp        0      0 0.0.0.0:68              0.0.0.0:*                           -
udp6       0      0 :::4443                 :::*