TAP Windows Adapter - 10 Mb/s only?

giaur

Hello,

I've sucessfully setup my OpenVPN configuration. Server is Linux and clients are Windows 7. But I'm not really satisfied with this, because of slow transfers inside my vpn. Windows clients use official OpnVPN gui. There is TAP Windows Adapter (it was added during OpenVPN Client installation) used for all vpn traffic. The problem is its speed - 10 Mb/s only.

Please don't tell me this value is not real network speed. I've performed simple test. When transfering data via vpn, TAP Windows Adapter usage reporting in Windows task manager is 99% and transfer speed is 1.1-1.3 Mbps (so, definitely 10 Mbps mode).

But switching to direct connection between the same machines, without using vpn causes increasing transfer rate to 2.5 - 3 MB/s (this is max possible with my ISPs). In any case, cpu load for each machine (clients and server) is low, so this is not out of resources issue.

So, is there any option to increase my vpn speed? Or, 10 Mbps is official OpenVPN's limit and there is nothing to do?

[deleted]

See this post: http://openvpn.net/archive/openvpn-users/2004-02/msg00041.html

10mbit is not actual speed. You may just meed to tweak the vpn. You also don't always get max speed over the vpn.

Are you using lzo compression?

giaur

Yes, lzo is enabled, this is my server.conf:

port 1194
proto udp
dev tun
ca /etc/openvpn/ca.crt
cert /etc/openvpn/server.crt
key /etc/openvpn/server.key
dh /etc/openvpn/dh1024.pem
server 10.8.0.0 255.255.255.0
ifconfig-pool-persist ipp.txt
#push "redirect-gateway def1 bypass-dhcp"
push "dhcp-option DNS 84.204.204.204"
push "dhcp-option DNS 62.233.233.233"
keepalive 10 120
comp-lzo
user nobody
group nogroup
persist-key
persist-tun
status openvpn-status.log
verb 3
client-to-client
topology subnet
client-config-dir ccd

And client.ovpn on Windows:

dev tun
client 
remote <server ip>
proto udp
port 1194 
nobind 
ca ca.crt
cert user.crt
key user.key
comp-lzo
verb 3

How to tweak my setup? In my case, I can see 10 Mbps only and it's not my hardware or isp limitations. Hamachi runs with max speed on the same hardware (direct udp connection).