Why does the vmxnet3 driver shipped with RHEL 6 update 2 drops small UDP packets?

Solution Verified - Updated -


  • After upgrading from RHEL6.1 to 6.2,loadbalancer does not work correctly.Before the upgrade only one LB was active (seen with ipvsadm -L) and used the virtual IP configured for the service. After the upgrade both LB are active (seen with ipvsadm -L) an both show the virtual IP for the configured service.
  • TFTP transfer times out after upgrading the kernel to RHEL 6 update 2
  • After upgrading to RHEL6.2, UDP or heartbeat packets are getting dropped when using vmxnet3 driver
  • vmxnet3 update in RHEL 6.2 broke small UDP packet transmission


  • RHEL 6 update 2

  • kernel-2.6.32-220.el6.i686 / kernel-2.6.32-220.2.1.el6.x86_64 / kernel-2.6.32-220.el6.x86_64

  • vmxnet3

  • Vmware ESX Host

Subscriber exclusive content

A Red Hat subscription provides unlimited access to our knowledgebase, tools, and much more.

Current Customers and Partners

Log in for full access

Log In

New to Red Hat?

Learn more about Red Hat subscriptions

Using a Red Hat product through a public cloud?

How to access this content