Forum: Wie mach ich was?
Topic: MTU optimieren
started by: Michael
Posted by Michael on Sep. 08 2017, 17:26
To set the best MTU value and optimize VPN speed, please perform the following steps:
First connect VPN. If you are using PureVPN Client then it will automatically create VPN connection named PureVPN. If you created the connection manually then it will appear in Step 3 and you need to modify the command given in Step 4.
1 Open “Command Prompt“. Make sure that you have Admin privileges.
On Windows XP, Vista and 7, Click on Start button and click on “Run“, type “cmd” and click “OK“.
On Windows 8, right click at bottom left corner and select “Command Prompt (Admin)”.
2Type the below command and hit enter to check current MTU value . Note down the current MTU value in case you want to revert changes.
netsh interface ipv4 show subinterfaces
3 Type the command below and hit enter.
ping < http://www.google.com > -f -l 1500
If the reply you get is “Packet needs to be fragmented but DF set.”, then you have to try a lower MTU value. Keep decreasing the value by 10, i.e. 1490, 1480, 1470 until you get a successful reply. Start increasing the MTU value with small increments after you get a successful reply. Eventually, you will arrive on a value on which packets will not fragment, add 28 to that value (IP / ICMP headers).For instance, if you got the last successful reply on 1470, then add 28 to it, 1470+28 = 1498.
4This number is your MTU value.
If you are using a LAN connection, then type the following command:
netsh interface ipv4 set subinterface PureVPN mtu=1498 store=persistent
OR
netsh interface ipv4 set subinterface “PureVPN” mtu=1498 store=persistent
where PureVPN is the VPN Connection name.
Recommended:
If some websites are not loading while connected to VPN then please try MTU 1200
netsh interface ipv4 set subinterface PureVPN mtu=1200 store=persistent
OR
netsh interface ipv4 set subinterface “PureVPN” mtu=1200 store=persistent