From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Cooper Subject: Re: Xen / EC2 network HVM device visibility Date: Wed, 30 Sep 2015 10:11:13 +0100 Message-ID: <560BA731.1090300@citrix.com> References: <2CDE7D7D-3862-4BE5-A4AF-95C192701975@supercoders.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <2CDE7D7D-3862-4BE5-A4AF-95C192701975@supercoders.com.au> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Andrew Stuart , xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org On 30/09/15 06:25, Andrew Stuart wrote: > As far as I can tell, Xen HVM domu guests detect and use the RTL8139 network card thus its not a hard requirement to use the PVHVM drivers. The rtl8139 (or e1000e, depending on configuration) are provided to HVM guests to cater to a Xen unaware configuration. It is expected that any Xen aware operating system use xen-netfront instead. > > On EC2 however, am I right in understanding that although EC2 is using Xen HVM, the RTL8139 network device is not available and therefore to get networking it is a requirement for PVHVM drivers? As part of booting and being Xen aware, there is a handover to disable the emulated card, to avoid the VM having two network interfaces on the same bridge with the same mac address. If you instruct your VM to boot without enabling any Xen PV drivers, you will likely still find an emulated card visible. ~Andrew