VPN（OpenVPN）に接続した後、VPSにアクセスできません。

2つの仮想プライベートサーバーがあり、OpenVPNを使用して1つのネットワークで動作するようにしたいと思います。それらはすべてDebianマシンです。

サーバー設定：

port 11194
proto udp6 # I know using udp6 instead of udp here is unnecessary
dev tap
ca ca.crt
cert server.crt
key server.key
dh dh2048.pem
server 10.8.0.0 255.255.255.0
push "redirect-gateway def1 bypass-dhcp"
push "dhcp-option DNS 208.67.222.222"
push "dhcp-option DNS 208.67.220.220"
keepalive 10 120
cipher AES-128-CBC
comp-lzo
user nobody
group nogroup
persist-key
persist-tun
status openvpn-status.log
log-append  openvpn.log
verb 3

クライアント設定：

client
port 11194
remote 86.xx.xx.190
cipher AES-128-CBC
dev tap
proto udp
nobind
auth-nocache
persist-key
persist-tun
verb 2
comp-lzo
keysize 128
key-direction 1
log-append openvpn.log
<ca>
[ca here]
</ca>
<cert>
[cert here]
</cert>
<key>
[key here]
</key>

Windowsクライアントは問題なくサーバーに接続でき、接続はうまく機能します。ただし、セカンダリVPS経由で接続しようとすると、次のようになります。

openvpn --config /path/to/cfg.ovpn

SSHセッションが終了し、サーバー全体にアクセスできず、そのパブリックIPアドレスを使用できなくなりました。その後、間違った接続を停止するには、クラウド管理パネルを介して強制的に再起動する必要がありました。私がここで何を間違っているのか？

クライアントのログファイルは次のとおりです。

Fri May  5 09:48:52 2017 OpenVPN 2.3.4 x86_64-pc-linux-gnu [SSL (OpenSSL)] [LZO] [EPOLL] [PKCS11] [MH] [IPv6] built on Nov 12 2015
Fri May  5 09:48:52 2017 library versions: OpenSSL 1.0.1t  3 May 2016, LZO 2.08
Fri May  5 09:48:52 2017 WARNING: No server certificate verification method has been enabled.  See http://openvpn.net/howto.html#mitm for more info.
Fri May  5 09:48:52 2017 UDPv4 link local: [undef]
Fri May  5 09:48:52 2017 UDPv4 link remote: [AF_INET]86.xx.xx.190:11194
Fri May  5 09:48:53 2017 VERIFY OK: depth=1, C=US, ST=CA, L=SanFrancisco, O=Fort-Funston, OU=MyOrganizationalUnit, CN=Fort-Funston CA, name=server, [email protected]
Fri May  5 09:48:53 2017 VERIFY OK: depth=0, C=US, ST=CA, L=SanFrancisco, O=Fort-Funston, OU=MyOrganizationalUnit, CN=server, name=server, [email protected]
Fri May  5 09:48:53 2017 WARNING: 'keydir' is present in local config but missing in remote config, local='keydir 0'
Fri May  5 09:48:53 2017 Data Channel Encrypt: Cipher 'AES-128-CBC' initialized with 128 bit key
Fri May  5 09:48:53 2017 Data Channel Encrypt: Using 160 bit message hash 'SHA1' for HMAC authentication
Fri May  5 09:48:53 2017 Data Channel Decrypt: Cipher 'AES-128-CBC' initialized with 128 bit key
Fri May  5 09:48:53 2017 Data Channel Decrypt: Using 160 bit message hash 'SHA1' for HMAC authentication
Fri May  5 09:48:53 2017 Control Channel: TLSv1, cipher TLSv1/SSLv3 DHE-RSA-AES256-SHA, 2048 bit RSA
Fri May  5 09:48:53 2017 [server] Peer Connection Initiated with [AF_INET]86.xx.xx.190:11194
Fri May  5 09:48:55 2017 TUN/TAP device tap0 opened
Fri May  5 09:48:55 2017 do_ifconfig, tt->ipv6=0, tt->did_ifconfig_ipv6_setup=0
Fri May  5 09:48:55 2017 /sbin/ip link set dev tap0 up mtu 1500
Fri May  5 09:48:55 2017 /sbin/ip addr add dev tap0 10.8.0.4/24 broadcast 10.8.0.255
Fri May  5 09:48:55 2017 Initialization Sequence Completed
Fri May  5 09:49:17 2017 event_wait : Interrupted system call (code=4)
Fri May  5 09:49:17 2017 Closing TUN/TAP interface
Fri May  5 09:49:17 2017 /sbin/ip addr del dev tap0 10.8.0.4/24
Fri May  5 09:49:17 2017 SIGHUP[hard,] received, process restarting
Fri May  5 09:49:17 2017 OpenVPN 2.3.4 x86_64-pc-linux-gnu [SSL (OpenSSL)] [LZO] [EPOLL] [PKCS11] [MH] [IPv6] built on Nov 12 2015
Fri May  5 09:49:17 2017 library versions: OpenSSL 1.0.1t  3 May 2016, LZO 2.08
Fri May  5 09:49:19 2017 WARNING: No server certificate verification method has been enabled.  See http://openvpn.net/howto.html#mitm for more info.
Fri May  5 09:49:19 2017 UDPv4 link local: [undef]
Fri May  5 09:49:19 2017 UDPv4 link remote: [AF_INET]86.xx.xx.190:11194
Fri May  5 09:49:19 2017 VERIFY OK: depth=1, C=US, ST=CA, L=SanFrancisco, O=Fort-Funston, OU=MyOrganizationalUnit, CN=Fort-Funston CA, name=server, [email protected]
Fri May  5 09:49:19 2017 VERIFY OK: depth=0, C=US, ST=CA, L=SanFrancisco, O=Fort-Funston, OU=MyOrganizationalUnit, CN=server, name=server, [email protected]
Fri May  5 09:49:20 2017 WARNING: 'keydir' is present in local config but missing in remote config, local='keydir 0'
Fri May  5 09:49:20 2017 Data Channel Encrypt: Cipher 'AES-128-CBC' initialized with 128 bit key
Fri May  5 09:49:20 2017 Data Channel Encrypt: Using 160 bit message hash 'SHA1' for HMAC authentication
Fri May  5 09:49:20 2017 Data Channel Decrypt: Cipher 'AES-128-CBC' initialized with 128 bit key
Fri May  5 09:49:20 2017 Data Channel Decrypt: Using 160 bit message hash 'SHA1' for HMAC authentication
Fri May  5 09:49:20 2017 Control Channel: TLSv1, cipher TLSv1/SSLv3 DHE-RSA-AES256-SHA, 2048 bit RSA
Fri May  5 09:49:20 2017 [server] Peer Connection Initiated with [AF_INET]86.xx.xx.190:11194
Fri May  5 09:49:22 2017 TUN/TAP device tap0 opened
Fri May  5 09:49:22 2017 do_ifconfig, tt->ipv6=0, tt->did_ifconfig_ipv6_setup=0
Fri May  5 09:49:22 2017 /sbin/ip link set dev tap0 up mtu 1500
Fri May  5 09:49:22 2017 /sbin/ip addr add dev tap0 10.8.0.4/24 broadcast 10.8.0.255
Fri May  5 09:49:22 2017 Initialization Sequence Completed