Packet loss into KVM virtual machine, drops in vnet TX counters

Solution Verified - Updated -

Issue

  • Packet loss into KVM virtual machine, drops in "tun_net_xmit"
  • Traffic inside the VM reports loss of data or in-application sequence numbers, most commonly seen with UDP traffic
  • Running dropwatch on a KVM hypervisor host shows the drops are in the tun_net_xmit function
  • ifconfig or ip -s link show "dropped" counters on vnetX tap interfaces into VMs

Environment

  • Red Hat Enterprise Linux
  • KVM virtualization
  • dropwatch
  • Unreliable transport protocol such as UDP (User Datagram Protocol)

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