)]}'
{"/COMMIT_MSG":[{"author":{"_account_id":16688,"name":"Rodolfo Alonso","email":"ralonsoh@redhat.com","username":"rodolfo-alonso-hernandez"},"change_message_id":"8db23576df8839d75f8260a6c9e8f8a21fb93e84","unresolved":true,"context_lines":[{"line_number":6,"context_line":""},{"line_number":7,"context_line":"ovs: disable IPv6 on taps created by create_tap before bringing them up"},{"line_number":8,"context_line":""},{"line_number":9,"context_line":"When Neutron asks os-vif to create the tap (ovs_create_tap), create_tap"},{"line_number":10,"context_line":"gives the tap the instance\u0027s MAC address and brings it up with IPv6 still"},{"line_number":11,"context_line":"enabled. The host kernel then derives the instance\u0027s own link-local"},{"line_number":12,"context_line":"address for the tap and runs duplicate address detection for it; that"}],"source_content_type":"text/x-gerrit-commit-message","patch_set":1,"id":"1aca4a57_ec248f8b","line":9,"range":{"start_line":9,"start_character":0,"end_line":9,"end_character":71},"updated":"2026-09-14 06:01:10.000000000","message":"nit: it is better to limit the line length to 72 chars https://docs.openstack.org/contributors/es_MX/common/git.html#body","commit_id":"70e9b383beb478620101d575344c6755302fe333"}],"/PATCHSET_LEVEL":[{"author":{"_account_id":16688,"name":"Rodolfo Alonso","email":"ralonsoh@redhat.com","username":"rodolfo-alonso-hernandez"},"change_message_id":"525b099056796dc0cdfeb18261c2329829e8c753","unresolved":false,"context_lines":[],"source_content_type":"","patch_set":1,"id":"f86df3dc_0b7b582a","updated":"2026-09-14 05:59:46.000000000","message":"This could explain the random issues we have been experiencing with ipv6 tests in tempest and neutron-tempest-plugin since we made this flag enabled by default.","commit_id":"70e9b383beb478620101d575344c6755302fe333"},{"author":{"_account_id":8313,"name":"Lajos Katona","display_name":"lajoskatona","email":"katonalala@gmail.com","username":"elajkat","status":"Ericsson Software Technology"},"change_message_id":"69392bedd9e0d2a650273c0f96e5f5bba16730ec","unresolved":false,"context_lines":[],"source_content_type":"","patch_set":1,"id":"4087c666_7fd30fb3","updated":"2026-09-14 09:17:41.000000000","message":"nice","commit_id":"70e9b383beb478620101d575344c6755302fe333"}],"releasenotes/notes/tap-disable-ipv6-f9dd0dd18fbe960f.yaml":[{"author":{"_account_id":11604,"name":"sean mooney","email":"smooney@redhat.com","username":"sean-k-mooney"},"change_message_id":"ede4e21bb588082e8f21500f13cd6f4eafb4e023","unresolved":true,"context_lines":[{"line_number":2,"context_line":"fixes:"},{"line_number":3,"context_line":"  - |"},{"line_number":4,"context_line":"    Tap devices created by the Open vSwitch plugin (when Neutron requests"},{"line_number":5,"context_line":"    ``ovs_create_tap``) now have IPv6 disabled before they are brought up."},{"line_number":6,"context_line":"    The tap is given the instance\u0027s MAC address, so with IPv6 enabled the"},{"line_number":7,"context_line":"    host derived the instance\u0027s own link-local address for it and ran"},{"line_number":8,"context_line":"    duplicate address detection for that address; the resulting neighbour"}],"source_content_type":"text/x-yaml","patch_set":1,"id":"ae9d4db8_a70de7d8","line":5,"range":{"start_line":5,"start_character":3,"end_line":5,"end_character":22},"updated":"2026-09-14 10:47:03.000000000","message":"note Open vSwitch plugin implies `ovs_create_tap`` only applies toe ml2/ovs\n\nbut `ovs_create_tap`` is actully used by all backends that supprot that supprot vif_type\u003dovs which include ovn and odl and well anything else that manages openvswich.","commit_id":"70e9b383beb478620101d575344c6755302fe333"},{"author":{"_account_id":11604,"name":"sean mooney","email":"smooney@redhat.com","username":"sean-k-mooney"},"change_message_id":"ede4e21bb588082e8f21500f13cd6f4eafb4e023","unresolved":true,"context_lines":[{"line_number":13,"context_line":"    This disables only the host\u0027s IPv6 stack on the tap, not IPv6 traffic"},{"line_number":14,"context_line":"    forwarded to or from the instance. Guest IPv6 remains enabled. The fix"},{"line_number":15,"context_line":"    applies to newly created tap devices; existing devices are not"},{"line_number":16,"context_line":"    reconfigured until recreated through the normal instance lifecycle."}],"source_content_type":"text/x-yaml","patch_set":1,"id":"9e1aac01_257a7016","line":16,"updated":"2026-09-14 10:47:03.000000000","message":"as far as im aware\nyou can use something like \n```\nsysctl -w net.ipv6.conf.default.addr_gen_mode\u003d1\n```\nto disabel all link local addresses for interfaces on the hsot\n\nalthouhg a beteer workaround is to use udev \n\n```\n# /etc/udev/rules.d/90-tap-no-ipv6-linklocal.rules\nACTION\u003d\u003d\"add\", SUBSYSTEM\u003d\u003d\"net\", KERNEL\u003d\u003d\"tap*\", \\\n    RUN+\u003d\"/usr/sbin/sysctl -q -w net.ipv6.conf.%k.addr_gen_mode\u003d1\"\n```\n\nsince that is more targeted.\n\nwith that said this is in socpe of os-vif to do.","commit_id":"70e9b383beb478620101d575344c6755302fe333"}]}