Finding and Setting MTU on Mac
Finding MTU on Mac Right so you have just moved house and your internet falls off when you connect to your works VPN - likelihood is your MTU is set too high for your ISP. Searching for this on the net there is a ton of misinformation. So usually the mac has a maximum MTU of 1500 for some ISP’S this limit needs to be set much lower. So first lets take a look at what your macs MTU currently is. ToDo this: 1.Open ‘Terminal’ 2.Type: " networksetup -getMTU en0" This will return you with what your MTU is currently set at. For Macs this is usually 1500. Now you need to test what is the maximum MTU you can use on your connection 3. In terminal enter: "ping -D -s 1500 www.google.com" , You will probably get the message ‘ping: sendto: Message too long' Procedure to find optimal MTU: If your MTU is currently set too low, for example 576, the following procedure will not be able to detect whether you have discovered the "Optimal MTU size"...