Differences

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--- eve-os:interface-naming [2026/08/20 14:53] – mc
+++ eve-os:interface-naming [2026/08/20 15:03] (current) – [Migration Note] mc
@@ Line 20: / Line 20: @@
   * Why bridge everything up front: so a bridge is already sitting there ready to accept app VIFs later, even on the management port itself, without needing a reboot or reconfig.
   * To pull this off without renaming anything visible, EVE renames the physical NIC to ''kethX'' and lets the bridge take over the ''eth0'' name.
-  * The bridge also takes over the original MAC address, so DHCP still hands out the same IP after an EVE update. ''kethX'' gets a different MAC (with the local bit set) so there's no collision.
-In short: ''eth0'' is the bridge. ''kethX'' is the real physical NIC sitting underneath it, demoted to a bridge port.
+===== MAC Address Behavior (version dependent) =====
+  * **EVE 17.0 and newer (PR #6167, merged Jul 2026):** ''ethX'' and ''kethX'' share the exact same MAC address. Testing showed this causes no problems; the Linux bridge FDB tolerates a duplicate local address by design, and NIM only assigns IP (including IPv6 link-local) to the ''ethX'' bridge, never to ''kethX'', so there's no collision.
+  * **Older EVE (pre-17.0, still true on 16.0/14.5/13.4-stable):** ''kethX'' got a different MAC than ''ethX'' by flipping the locally-administered bit. This was a conservative design choice, not a technical requirement, and it's what could make a box look like it has two MACs on one port, which some security software flagged.
+  * Check your EVE version before assuming which behavior you're looking at.
 ===== bnX / bridgeX: Bridges for Network Instances =====
@@ Line 38: / Line 41: @@
 | vifX | App/container virtual interface | Any NI, attached to its bridge |
-===== Migration Note =====
-On tenant offboarding/re-onboarding, a stale ''kethX'' left over from a previous config is a real failure mode. If the bridge/keth pairing didn't tear down cleanly, the rename can conflict with the next setup. Worth checking during migration troubleshooting.
-===== Source =====
+===== Sources =====
-Confirmed against the lf-edge EVE design doc "K3S flat network in EVE" (wiki.lfedge.org), which describes the bridge-per-port and keth renaming mechanism directly.
+  * lf-edge EVE design doc "K3S flat network in EVE" (wiki.lfedge.org), original bridge-per-port and keth renaming design.
+  * [[https://github.com/lf-edge/eve/pull/6167|lf-edge/eve PR #6167]], "dpcreconciler: drop alternativeMAC", merged Jul 17 2026, backported to 17.0. Confirms current MAC-sharing behavior and drops the old locally-administered-bit distinction.