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Date: Fri, 8 Nov 2019 15:44:07 -0800
From: Stephen Hemminger <stephen@networkplumber.org>
To: Maxime Coquelin <maxime.coquelin@redhat.com>, Tiwei Bie
 <tiwei.bie@intel.com>, Zhihong Wang <zhihong.wang@intel.com>
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Subject: [dpdk-dev] vtap0 device creation (bug)?
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When I create a virtio-user device with rte_hotplug it creates a kernel device (ie vtap0).
This is normal an the device has ifindex N.

But later when device is configured an started the original vtap0 device is deleted
and a new one is created (with ifindex N+1).  This seems like a bug, if nothing
else it unnecessary overhead and link flapping for routing daemons.

Noticed only while tracking down a bug where after vtap was created the
address was being set, but then disappearing.

Is this intentional? Is it documented?