Linode Forum
https://forum.linode.com/

openvpn: new client - slow connection, same config - why??
https://forum.linode.com/viewtopic.php?f=19&t=10057		 Page 1 of 1
Author:  cattani [ Tue May 07, 2013 4:48 pm ]
Post subject:  openvpn: new client - slow connection, same config - why??
hy!
I use openvpn to tunnel my internet traffic over linode. for years it worked with 15mbit (i´m far away from my linode :).

recently i changed internet subscription from 20mbps docsis to 55mbps docsis - same provider, new modem (technicolor), didnt realize it changed a thing, apart that the line has 55mbps with direct connections.

then my win7 client crashed.

re-installed win7, installed openvpn, using old config.

now openvpn is max 5mbps, with the old client it was approx. 15 mbit.

plz help me debug this, i dont see the problem...

here´s the client config

Code:
proto udp
ns-cert-type server 
tls-client
client
mssfix
dev-node tap
remote x.x.x.x 32799
ca xx.crt
cert xxx.crt
key xxxx.key


server config is

Code:
port 32799 
proto udp
dev tap0
ca xxx.crt
cert xxxx.crt
key xxxx.key
dh dh512.pem
server 10.8.0.0 255.255.255.0
duplicate-cn
keepalive 10 120
push "redirect-gateway def1 bypass-dhcp"
push "redirect-gateway def1"
push "dhcp-option DNS 10.8.0.1"
push "route 10.8.0.0 255.255.255.0"
max-clients 25
client-to-client
status /var/log/openvpn.log
verb 4
Author:  cattani [ Tue Dec 10, 2013 3:26 pm ]
Post subject:  Re: openvpn: new client - slow connection, same config - why
hy!
i did some testing and nothing changed, until i connected to the openvpn server using a macbook on another internet line, and voila - 13mbit downstream.

so i let the technician check my internet line. he changed the modem to a new one, but same product (technicolor 7200). same dismal speed of 2-4 mbit.

now i did some testing using "netalyzr" (http://netalyzr.icsi.berkeley.edu/index.html) while the openvpn tunnel was up and it says:

"you cannot send fragmented udp traffic, fragmented udp traffic could be received. your modem or firewall seems not be capable of handling udp fragmentation. the biggest sent udp packet was 1383 bytes". another test says that the biggest udp packet was 1393.

could it be that i have a fragmentatin issue?

i now tried setting
tun-mtu 1383
or
tun-mtu 1393
or even
tun-mtu 1333
on server and client but nothing changed..

how do i have to handle this fragmentation issue?
thx!
Page 1 of 1 All times are UTC-04:00
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/