Using VPN Gate by a debian client

[JCurry]

I use debiian 8.1 x64,
and I installed openvpn and gadmin-openvpn-client from a debian repository.

I tried to connect by a .ovpn file,which is displayed on
http://www.vpngate.net/en/
When I choosed the .ovpn file of vpn725298766.opengw.net in Canada,
http://www.vpngate.net/common/openvpn_d ... _1686.ovpn
I could make a connection to the VPNGate server and browse various Web sites.

$ sudo openvpn --config ~/Desktop/vpngate_vpn725298766.opengw.net_udp_1686.ovpn
Tue Aug 25 02:45:59 2015 OpenVPN 2.3.4 x86_64-pc-linux-gnu [SSL (OpenSSL)] [LZO] [EPOLL] [PKCS11] [MH] [IPv6] built on Dec 1 2014
Tue Aug 25 02:45:59 2015 library versions: OpenSSL 1.0.1k 8 Jan 2015, LZO 2.08
Tue Aug 25 02:45:59 2015 WARNING: No server certificate verification method has been enabled. See http://openvpn.net/howto.html#mitm for more info.
Tue Aug 25 02:45:59 2015 Socket Buffers: R=[212992->131072] S=[212992->131072]
Tue Aug 25 02:45:59 2015 UDPv4 link local: [undef]
Tue Aug 25 02:45:59 2015 UDPv4 link remote: [AF_INET]67.204.212.90:1686
Tue Aug 25 02:46:00 2015 TLS: Initial packet from [AF_INET]67.204.212.90:1686, sid=7c0c6198 bde9c4c0

Doesn't we need to create a client key?
Its procedure is shown in the section "Generate certificates & keys for 3 clients"
at
https://openvpn.net/index.php/open-sour ... howto.html

And I visited sites which show the browser's environment variable.
Then,some time in
REMOTE_HOST
REMOTE_ADDR
my IP address and ISP's hostname appeared.
And the other time VPNGate server's IP address and hostname were there.
The function of the VPNGate server wasn't stable.
Is this a problem of configuration?
(And,people who uses VPNGate,which VPNGate server do you use?)