Requested revision
Standard: | 802.1AX-2014 | Clause: | 9.3.2 |
Clause title: | Intra-Portal Link |
Rationale for revision
When a DRNI portal is created, it is critical for the LACP partner of
the portal to be configured with one and only one aggregator using the
same key value as the ports connected to the DRNI portal. Failure to
do this will result in a loop if the IPL in the Portal fails. The
necessity of this configuration for loop-free fault recovery is not
mentioned anywhere in the document.
Proposed text
Add the following paragraph to the end of 9.3.2 (prior to 9.3.2.1):
The operation of the DR Function state machines and Control Protocol
specified in the following sections assures that if a loss of connectivity
via the IPL results in a Portal System being unable to communicate with
other Portal Systems in the Portal, those Portal Systems will used different
key values in LACPDUs exchanged on the Aggregation Links attached to the
Portal Systems. This prevents Aggregation Links attached to Portal Systems
that cannot communicate via an IPL from being selected for the same LAG.
It is possible that these Aggregation Links could become operational
in separate LAGs, however, potentially creating a communication loop through
the LACP partner of the Portal Systems. To prevent this loop it is essential
that the LACP partner of the DRNI Portal be configured such that there is
one and only one Aggregator with the same key value as the Aggregation Ports
connected to the DRNI Portal.
Impact on existing networks
If there is an existing network with the LACP partner of a DRNI Portal that is
not already configured in this matter, then a configuration change would be
necessary to avoid the possibility of creating a loop upon the failure of an IPL.
Originator
Name: | Stephen Haddock | Email: | shaddock@stanfordalumni.org |
Affiliation: | Stephen Haddock Consulting LLC | ||
Submitted: | 2015-05-18 |