commit 017bc7012dc018df91558470c296aabf8089a07d
author Sam Balana <sbalana@google.com> Tue Oct 27 06:42:09 2020 +0000
committer CQ Bot <commit-bot@chromium.org> Tue Oct 27 06:42:09 2020 +0000
tree 0a5d28402531e89fce74ed48b414b1ce8d430de7
parent da96c3321bff377c5464120b78318b8e861c249f

[netstack] Reland NUD with additional logs

This is a reland of 6252f928d165275915930f4fd177d8eb4f16f68c

Flip the flag to replace the current implementation of ARP and NDP
through linkAddrCache, with an implementation of NUD through
neighborCache. Switching to using NUD for both ARP and NDP is beneficial
for the reasons described by RFC 4861 Section 3.1:

  "[Using NUD] significantly improves the robustness of packet delivery
  in the presence of failing routers, partially failing or partitioned
  links, or nodes that change their link-layer addresses. For instance,
  mobile nodes can move off-link without losing any connectivity due to
  stale ARP caches."

  "Unlike ARP, Neighbor Unreachability Detection detects half-link
  failures and avoids sending traffic to neighbors with which two-way
  connectivity is absent."

Also add additional logging for NUD events so we can better debug
network issues that may come from flipping this flag.

Multiply: `[
  {
    "name": "host_x64/package_manager_test",
    "total_runs": 30
  }
]`

Bug: 61723
Bug: 62788
Change-Id: I6cae157c706bdef089d53de88a03b29c2e3b4aa7
Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/441165
Commit-Queue: Sam Balana <sbalana@google.com>
Reviewed-by: Tamir Duberstein <tamird@google.com>
Testability-Review: Tamir Duberstein <tamird@google.com>