NAME

hostRecvRaRFlag - Verifying that a RA sets a IsRouter flag true


TARGET

Host only


SYNOPSIS

  hostRecvRaRFlag.seq [-tooloption ...] -p hostRecvRaRFlag.def


INITIALIZATION

  1. Create an neighbor cache entry for TN where a IsRouter flag is FALSE.
  2. Set its state to REACHABLE.
  3. Cache either TN's LLA or a bogus LLA.


Cache a LLA of TN

  TN                 NUT
  ----------------------
  State: NONCE (for TN)

==== echo-request ===> src=TN's link-local dst=NUT's link-local
State: INCOMPLETE (for TN)
<=== multicast NS ==== src:NUT's link-local dst:solicited-node[TN's link-local] target=TN's link-local SLLA=NUT's LLA timeout: RETRANS_TIMER * MAX_MULTICAST_SOLICIT
==== solicited NA ===> src:TN's link dst:NUT's link-local R=0, S=1, O=1 target=TN's link-local TLLA=TN's LLA
State: REACHABLE (for TN)


Cache a bogus LLA

  TN                 NUT
  ----------------------
  State: NONCE (for TN)

==== echo-request ===> src=TN's link-local dst=NUT's link-local
State: INCOMPLETE (for TN)
<=== multicast NS ==== src:NUT's link-local dst:solicited-node[TN's link-local] target=TN's link-local SLLA=NUT's LLA timeout: RETRANS_TIMER * MAX_MULTICAST_SOLICIT
==== solicited NA ===> src:TN's link dst:NUT's link-local R=0, S=1, O=1 target=TN's link-local TLLA=a bogus LLA (0:0:0:0:a9:a9)
State: REACHABLE (for TN)


TEST PROCEDURE

hostRecvRaRFlag verifies that a RA sets a IsRouter flag true.

  TN                 NUT
  ----------------------

State: REACHABLE (for TN), NONCE(for X)
==== unsolicited RA ===> src=X's link-local dst=all-node M=0, O=0 RouterLifetime=10 ReachableTime=0 RetransTimer=0 w/ SLLA Prefix Option: L=1, A=1 ValidLifetime=2592000 PreferredLifetime=604800 Prefix=3ffe:501:ffff:100::/64
State: REACHABLE (for TN), STALE(for X)
==== solicited NA ===> src:X's link dst:NUT's link-local R=1, S=1, O=1 target=X's link-local w/ TLLA
Wati for 2 sec to ignore DAD NS
State: REACHABLE (for TN, X)
==== echo-request ===> src=off-link global, but LLA is X's one dst=NUT's global
<=== Judgment #1: echo-reply ==== src=NUT's global dst=off-link global, but LLA is X's one
==== unsolicited RA ===> src=TN's link-local dst=all-node M=0, O=0 RouterLifetime=600 ReachableTime=0 RetransTimer=0 w/ or w/o SLLA Prefix Option: L=1, A=1 ValidLifetime=2592000 PreferredLifetime=604800 Prefix=3ffe:501:ffff:100::/64
State: REACHABLE/STALE (for TN), REACHABLE (for X)
Wait (10 sec) for X's router lifetime to be expired
==== echo-request ===> src=off-link global, but LLA is TN's one dst=NUT's global
<=== Judgment #3: echo-reply ==== src=NUT's global dst=off-link global, but LLA is TN's one
State: REACHABLE/DELAY (for TN), REACHABLE (for X)


JUDGMENT

  1. NUT throw an echo-reply to the default router (i.e. X).

2. RA set IsRouter flag.
6.3.4. Processing Received Router Advertisements
After extracting information from the fixed part of the Router Advertisement message, the advertisement is scanned for valid options. If the advertisement contains a Source Link-Layer Address option the link-layer address SHOULD be recorded in the Neighbor Cache entry for the router (creating an entry if necessary) and the IsRouter flag in the Neighbor Cache entry MUST be set to TRUE. If no Source Link-Layer Address is included, but a corresponding Neighbor Cache entry exists, its IsRouter flag MUST be set to TRUE. The IsRouter flag is used by Neighbor Unreachability Detection to determine when a router changes to being a host (i.e., no longer capable of forwarding packets). If a Neighbor Cache entry is created for the router its reachability state MUST be set to STALE as specified in Section 7.3.3. If a cache entry already exists and is updated with a different link-layer address the reachability state MUST also be set to STALE.
============+===========+=============================== RA received by tne NUT | NUT's Neighbor Cache State ------------+-----------+---------+--------------------- Destination | SLLA | Current | New ============+===========+=========+===================== all-node | none | 0 | 1 ------------+-----------+---------+--------------------- all-node | same | 0 | 1 ------------+-----------+---------+--------------------- all-node | different | 0 | 1 ============+===========+=========+=====================
3. NUT throw an echo-reply to NUT instead of X.


TERMINATION

  Send the following RAs to clear the Default Router List:
  - RA (src: TN) with RouterLifetime=0
  - RA (src: X)  with RouterLifetime=0


NOTE

  The test does not invoke any remote command.


SEE ALSO

  perldoc V6evalTool
  perldoc V6evalRemote