The primary issue with MTU size occurs when encapsulation is taking place between sites that only support 1500 byte MTU. It would be highly desirable to be able to increase the MTU size over the WAN.
Aug 02, 2018 WHAT IS THE BEST MTU FOR GAMING? (Lower Ping?) - YouTube Jun 27, 2018 IP OSPF MTU-Ignore Command - Cisco A situation can occur where the interface MTU is at a high value, for example 9000, while the real value of the size of packets that can be forwarded over this interface is 1500. If there is a mismatch on MTU on both sides of the link where OSPF runs, then the OSPF adjacency will not form because the MTU value is carried in the Database MTU settings on a 3750 switch - Cisco Community Routing MTU size is 1500 bytes. When I check the Gig switchports, the MTU is 9000, as expected: Switch#sh int gi 1/0/3 MTU 9000 bytes. However, when I check a L3 VLAN interface. Switch#sh int vlan 10 Vlan10 is up, line protocol is up MTU 1500 bytes
Ping Test to determine Optimal MTU Size on Router | Answer
L2TP VPN MTU Issues - Cisco Community I played with the settings, but we'd lose connectivity to our other customers, so I ended up setting it back to what I had set it to before (ip mtu 1460 and ip tcp adjust-mss 1420) and suddenly I can pass 1452 size packets, and the customer's L2TP VPN conneciton is working again. It worked for another two weeks, and then it stopped working again.
IPv4 - Wikipedia
MTU Size Issues | Network World One method to test and detect a reduced MTU size is to use a ping with a large packet size. Here are some examples of how to do this. C:\Users\ScottHogg> ping -l 1500 192.168.10.1 Jumbo frame - Wikipedia The frame size used by an end-to-end connection is typically limited by the lowest frame size in intermediate links. 802.5 Token Ring can support frames with a 4464-byte MTU, FDDI can transport 4352 byte, ATM 9180 byte and 802.11 can transport 7935 byte MTUs. Mikrotik MTU9200 - YouTube Nov 26, 2012