mutli-homing behavior with primary path disabled in the network.

Anand N Ilkal <anandnilkal@gmail.com> Mon, 22 November 2010 09:58 UTC

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Subject: mutli-homing behavior with primary path disabled in the network.
From: Anand N Ilkal <anandnilkal@gmail.com>
To: tsvwg@ietf.org
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Date: Mon, 22 Nov 2010 09:58:45 -0000
X-Original-Date: Mon, 22 Nov 2010 15:29:38 +0530
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Hello,

I have a multi-home association between Node A(IP1, IP2) and Node B(IP3,
IP4). IP1 and IP3 are configured as primary IP's.

A static route is configured between Node A and Node B for IP1 and IP3.
Hence it will always take this path for message exchange.
Now at the intermediate node this route is disabled. Hence no message reach
other end using IP1 and IP3.

It is observed that even HEARTBEAT's are not exchanged between IP1 and IP3.
Since secondary path is available, the messages are
exchanged between IP2 and IP4. in addition to this all message are tried on
the primary path first and then are sent on the secondary path.

1. How long SCTP tries sending message on primary path? or it tries for the
lifetime of the association?
2. How the decision of forbiding primary path is taken? is this the job of
SCTP layer or IP layer beneath it? or it wont take such decision?
3. when is the message exchange is resumed on primary path?


-- 
with regards,
Anand kumar Ilkal