From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: Re: vif-bridge: ip link set failed, "name" too long Date: Fri, 26 Jun 2015 08:10:51 +0100 Message-ID: <1435302651.17598.29.camel@citrix.com> References: <20150625113648.GK3393@perard.uk.xensource.com> <1435233219.32500.53.camel@citrix.com> <558CF124.6010504@suse.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <558CF124.6010504@suse.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Jim Fehlig Cc: Anthony PERARD , Xen Devel List-Id: xen-devel@lists.xenproject.org On Fri, 2015-06-26 at 00:28 -0600, Jim Fehlig wrote: > On 06/25/2015 05:53 AM, Ian Campbell wrote: > > On Thu, 2015-06-25 at 12:36 +0100, Anthony PERARD wrote: > >> Error: argument "tap695cf459-b0-emu" is wrong: "name" too long > > Under Linux IFNAMSIZ is 16, whereas this is 18 characters. > > > > Since our suffix is "-emu" we are adding 4 to the original 14, so we > > could/should pick a 2 character suffix to distinguish PV from emulated > > interfaces. "-e" perhaps? > > I'm not familiar with Neutron, but might this break some rules or filters it > creates based on the name? Appending stuff to a user-provided name doesn't seem > right. The issue is that we have two devices (the PV vif and the emulated one) and they cannot have the same name, so we have to do something to one of them. It could well be the case that this means we need to change Neutron too. [...] > I realize that doesn't help much if the guest has no pv network driver. I wonder > how this is handled in KVM? In the libvirt qemu driver, the default interface > model is rtl8139 if is not specified. Does nova add type='virtio'/> to interfaces for KVM instances? Is it expected that the guest > OS has a virtio network driver? I don't know, but my suspicion is that QEMU/KVM is able to route both virtio and emulated device traffic over the same tap interface, since both originate in the same process. We sadly don't have that liberty. If openstack is already assuming virtio only then that would of course be wonderful for us and we should do the same... Ian.