)]}'
{"specs/liberty/approved/libvirt-vnic-network-identification.rst":[{"author":{"_account_id":13734,"name":"Nell Jerram","email":"nell@tigera.io","username":"neiljerram"},"change_message_id":"433b5ca0ad40aff4e3ea03762cf0334ec64319d9","unresolved":false,"context_lines":[{"line_number":12,"context_line":""},{"line_number":13,"context_line":"An instance may have network interfaces connected to very different networks."},{"line_number":14,"context_line":"When DHCP isn\u0027t used in favour of a different management system, the latter"},{"line_number":15,"context_line":"needs a way to know which vNIC is connected to which network so that it can"},{"line_number":16,"context_line":"configure the network interfaces appropriately. If a guest agent is present and"},{"line_number":17,"context_line":"the various network interfaces have unique MAC addresses, the Nova API can"},{"line_number":18,"context_line":"report the interfaces\u0027s names as they appear inside the guest. If one or both"}],"source_content_type":"text/x-rst","patch_set":1,"id":"1af86dd1_2d401556","line":15,"updated":"2015-06-12 16:29:30.000000000","message":"I\u0027m confused - that sounds like information that Neutron would have; with the vNIC mapping to a port object, and the network to a network.  So surely that information is already available?","commit_id":"25c3150164d3dcb32ca3a427979d80c640c0781a"},{"author":{"_account_id":13734,"name":"Nell Jerram","email":"nell@tigera.io","username":"neiljerram"},"change_message_id":"433b5ca0ad40aff4e3ea03762cf0334ec64319d9","unresolved":false,"context_lines":[{"line_number":19,"context_line":"of those conditions are not met, Nova can\u0027t know for sure how devices are named"},{"line_number":20,"context_line":"and ordered inside a guest, but the API can report a device index indicating a"},{"line_number":21,"context_line":"best-effort attempt to know the order in which vNICs are ordered inside the"},{"line_number":22,"context_line":"guest."},{"line_number":23,"context_line":""},{"line_number":24,"context_line":"Problem description"},{"line_number":25,"context_line":"\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d"}],"source_content_type":"text/x-rst","patch_set":1,"id":"1af86dd1_300e2a35","line":22,"updated":"2015-06-12 16:29:30.000000000","message":"Really confused, I\u0027m afraid.  How can Nova know anything about what is happening inside the guest?  Is this spec related to a particular guest OS that you have in mind?","commit_id":"25c3150164d3dcb32ca3a427979d80c640c0781a"},{"author":{"_account_id":1779,"name":"Daniel Berrange","email":"berrange@redhat.com","username":"berrange"},"change_message_id":"d271a7eef414bf1c3e90dd9aa0fff8fba6bb7fe3","unresolved":false,"context_lines":[{"line_number":59,"context_line":"device_name in the servers virtual interfaces API [1]. If either or both of"},{"line_number":60,"context_line":"those conditions are not met, Nova can fall back to a best effort attempt to"},{"line_number":61,"context_line":"report a device order. To do so we add a device_index field to the virtual"},{"line_number":62,"context_line":"interfaces API."},{"line_number":63,"context_line":""},{"line_number":64,"context_line":"Currently, the order in which the user specifies vNICs at instance boot time is"},{"line_number":65,"context_line":"the order in which they end up in the libvirt XML. This in turn becomes their"}],"source_content_type":"text/x-rst","patch_set":1,"id":"fa32b979_609a6765","line":62,"updated":"2015-06-16 13:04:55.000000000","message":"I\u0027m really loathe to see the Nova API get into the business of reporting information about configuration inside the guest OS. I think Nova should exclusively focus on host management \u0026 reporting. If a systems management tool needs to extract information from the guest OS, there are plenty of pre-existing solutions that can be used for that purpose. \n\nNB, MAC address correlation is not nearly as easy as you might suggest. First, there is no 1-1 mapping between guest devices and host side devices. 2 host devices can have been bonded together into 1 logical guest device, with both members of that bond adopting the same MAC address. That bond device might have been then added to a bridge device. So for 1 host MAC address, their can be 4 guest devices with that MAC. Even on their own, NICs can have their MACs changed, though Nova\u0027s anti-spoofing rules would usualyl block that if enabled. It is valid to have multiple NICs with the same MAC address - MAC addresses are only required to be unique within a single logical network segment.  I just don\u0027t think the Nova API should be trying to untangle this mess itself.\n\nSo I think Nova API should just be reporting what NICs are configured against the guest, and let the systems management tool can take on the job of correlating that with data it obtains from the guest OS directly..","commit_id":"25c3150164d3dcb32ca3a427979d80c640c0781a"},{"author":{"_account_id":8864,"name":"Artom Lifshitz","email":"notartom@gmail.com","username":"artom"},"change_message_id":"6c1be9da99236aefdd61fc247c06d5f979679f5f","unresolved":false,"context_lines":[{"line_number":59,"context_line":"device_name in the servers virtual interfaces API [1]. If either or both of"},{"line_number":60,"context_line":"those conditions are not met, Nova can fall back to a best effort attempt to"},{"line_number":61,"context_line":"report a device order. To do so we add a device_index field to the virtual"},{"line_number":62,"context_line":"interfaces API."},{"line_number":63,"context_line":""},{"line_number":64,"context_line":"Currently, the order in which the user specifies vNICs at instance boot time is"},{"line_number":65,"context_line":"the order in which they end up in the libvirt XML. This in turn becomes their"}],"source_content_type":"text/x-rst","patch_set":1,"id":"fa32b979_e7d766eb","line":62,"in_reply_to":"fa32b979_609a6765","updated":"2015-06-16 15:39:54.000000000","message":"You\u0027re making a good point about Nova not reporting configuration inside the guest OS.\n\nThe thing is, operators do have this problem of \"I\u0027m not using DHCP and I want to know what interface inside the guest is connected to what network outside of it.\"\n\nIf Nova\u0027s not going to help them do it (for completely legitimate reasons), can we point them in the directions of solutions that do solve that problem? You mention that \"there are plenty of pre-existing solutions that can be used for that purpose.\" What are some exaple of those solutions that we can present to operators who have this problem?","commit_id":"25c3150164d3dcb32ca3a427979d80c640c0781a"}]}