What is the maximum MTU size for VMs in Google Cloud?

The maximum MTU (Maximum Transmission Unit) size for VMs in Google Cloud is 1,460 bytes. This value is specifically chosen to accommodate the overhead of the additional headers that are added when using the Virtual Private Cloud (VPC) network configurations in Google Cloud. When taking into account other network encapsulations such as VPN, the effective payload space available for data transfer is limited to this size to avoid fragmentation.

In typical Ethernet networks, the standard MTU size is 1,500 bytes; however, in Google Cloud, the configuration requires a slight adjustment downwards to account for various network headers. Therefore, the reduction to 1,460 bytes is made to ensure efficient handling of packets within the cloud infrastructure while still maintaining optimal performance and minimizing packet fragmentation.

Understanding MTU size is crucial in network design and performance optimization within Google Cloud, especially when dealing with network-intensive applications or services. This knowledge helps in configuring components such as load balancers and firewalls that must align with the established MTU settings to ensure seamless data transfer across the network.