After upgrading to VMware NSX Data Center for vSphere 6.4.2 or 6.4.3, or a fresh install of VMware NSX Data Center for vSphere 6.4.2 or higher version, you experienced these symptoms:
This issue occurs because the NSX Edge is used as a one-arm LB configuration with a higher MTU size of 9000 than the client's 1500 MTU size.
This issue is resolved in VMware NSX for vSphere 6.4.4.
Workaround:
Change the MTU size of the NSX Edge to 1500.