Path MTU black holes can result in network performance/connectivity issues
Applies to
Environments where endpoints support a larger MTU(Maximum Transition Unit) than the smallest MTU in the path.
Issue
- User environments where Path MTU is not successfully discovered can experience issues with both network performance as well as general connectivity issues.
- The performance issues might stem from intermediate devices performing IP fragmentation on large MTU packets, or endpoints having to reassemble.
- Connectivity issues usually occur when a large MTU frame fails to traverse the network, leading to the re-transmission of this packet until one of the endpoints gives up and resets the connection.