Hi folks.
I have a simple OpenVPN setup, based on the default sample configuration files, dev tun, with proto udp, port 1194. Everything works fine, can ping everything, etc. ...
After some random period of time suddenly internet sites start to respond terribly slow.
Especially google and google-related domains seem to slow down everything.
Google or Youtube need up to 10 or 15 minutes to load, other sites seem to get stuck with the browser saying that they wait for some scripts to finish from google-analitycs, or some other google-friendly domain ...
At the same time other sites, wich seem to have nothing in common with google load instantly.
Facebook for example, Yahoo, DeviantArt, ... they load instantly after entering the URL in the browser
Ping gives good results on google, can dig DNS and no errors anywhere.
My secondary linux box on the same network withoput openVPN loads google instantly.
The OpenVPN server itself loads pages instantly. A guest OS in virtualbox loads pages instantly.
The strange thing is, that even if the slowdown starts, and I stop OpenVPN the slowdown is presistent.
Rebooting the mashine helps. ...
I set now a static IP on my local lan. 192.168.1.99, gateway is 192.168.1.1.
ip route
10.8.0.1 via 10.8.0.9 dev tun0
10.8.0.9 dev tun0 proto kernel scope link src 10.8.0.10
192.168.1.0/24 dev eth2 proto kernel scope link src 192.168.1.99 metric 1
default via 192.168.1.1 dev eth2 proto static
ifconfig
eth2 Link encap:Ethernet HWaddr BC:AE:C5:E1:AF:C2
inet addr:192.168.1.99 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::beae:c5ff:fee1:afc2/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:4091024 errors:0 dropped:0 overruns:0 frame:0
TX packets:3475796 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:2790453695 (2.5 GiB) TX bytes:3081772468 (2.8 GiB)
Interrupt:48 Base address:0x6000
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:24728 errors:0 dropped:0 overruns:0 frame:0
TX packets:24728 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:1592220 (1.5 MiB) TX bytes:1592220 (1.5 MiB)
tun0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
inet addr:10.8.0.10 P-t-P:10.8.0.9 Mask:255.255.255.255
UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1
RX packets:6577 errors:0 dropped:0 overruns:0 frame:0
TX packets:6031 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:5040095 (4.8 MiB) TX bytes:457452 (446.7 KiB)
The OpenVPN server config file
proto udp
port 1194
dev tun
tls-server
ca /etc/openvpn/keys/ca.crt
cert /etc/openvpn/keys/r2.crt
key /etc/openvpn/keys/r2.key
dh /etc/openvpn/keys/dh1024.pem
mode server
# The server's virtual endpoints
ifconfig 10.8.0.1 10.8.0.2
# Pool of /30 subnets to be allocated to clients.
ifconfig-pool 10.8.0.4 10.8.0.255
# Push route to client to bind it to our local
# virtual endpoint.
push "route 10.8.0.1 255.255.255.255"
# Push any routes the client needs to get in
# to the local network.
### push "route 192.168.0.0 255.255.255.0"
# Push DHCP options to Windows clients.
### push "dhcp-option DOMAIN vpn.d250.hu"
### push "dhcp-option DNS 192.168.0.1"
### push "dhcp-option WINS 192.168.0.1"
# Client should attempt reconnection on link
# failure.
keepalive 10 60
# Delete client instances after some period
# of inactivity.
inactive 600
# Route the --ifconfig pool range into the
# OpenVPN server.
route 10.8.0.0 255.255.255.0
# The server doesn't need privileges
user openvpn
group openvpn
# Keep TUN devices and keys open across restarts.
persist-tun
persist-key
verb 4
And then, at one point, the response time get back to normal again ...
.. the slowdown seem to happen especially at night.
Any ideas for the bughunting? :)
