Re: [libvirt] [RFC] The Quest for Domain-IP Mapping Continues...

On Fri, Dec 5, 2014 at 3:33 PM, Daniel P. Berrange <berrange(a)redhat.com&gt; wrote: > On Fri, Dec 05, 2014 at 12:20:03AM +0530, Nehal J Wani wrote: >> If you remember correctly, about 1.2 years ago, we had... >> https://www.redhat.com/archives/libvir-list/2013-September/msg00351.html >> >> In short, the patch proposed a generalized mechanism for finding out >> IP addresses, with flags for choosing method(s) (SNOOP|LEASE|AGENT). >> >> But since not all methods were supported (only qemu-ga worked), the >> API was deferred. >> >> After exploring a bit, it seems that in all, we can have: >> (i) Leases Method >> (ii) Qemu Guest Agent >> (iiI) DHCP Snooping (exists, but isn't publicly exposed?) >> (iv) ARP Snooping (we can ask the virtual network interfaces to share >> their arp tables with the public?) >> >> Now that we have the dhcp-leases API fully furnished, why not visit >> the qemu-guest-agent again? >> >> OP1. Should we have separate APIs + virsh commands for each one of >> these and then combine them together under >> virDomainInterfaceAddresses? >> - If each one has to be a different API and then combined later, then >> what should be the corresponding name for the virsh command for >> exposing the querying guest agent API? >> OP2. Implement virDomainInterfaceAddresses API with two flags, one for >> dhcp-leases and another for qemu-ga and keep adding others whenever >> they are completed? > > I don't see any real reason to have separate APIs for each method. > The API signature will be the same in all cases, so having a single > virDomainGetInterfaceAddrs() method with a bunch of flags to control > what data source is used is preferrable. I'd expect the DHCP leases > method to be used as the default, since that's the most likely method > to succeed in the common case. So, should I go ahead and redo that patch, with two flags enabled?