[trill] Nickname Selection

Mahesh Akula <mahesh.akula36@gmail.com> Tue, 08 May 2012 17:24 UTC

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From: Mahesh Akula <mahesh.akula36@gmail.com>
To: Donald Eastlake <d3e3e3@gmail.com>
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Subject: [trill] Nickname Selection
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Hi Donald,

In RFC 6325 3.7.3, i'm troubling understanding below statement, can you
please help clarify?

First it says, node with higher IS-IS ID keeps the nickname, then it says, *if
there is a tie in priority* then node with higher IS-IS system ID keeps the
nickname.  It gives meaning that IS-IS ID and nickname priority are same??

Each RBridge is responsible for ensuring that its nickname or each
      of its nicknames is unique.  If RB1 chooses nickname x, and RB1
      discovers, through receipt of an LSP for RB2 at any later time,
      that RB2 has also chosen x, *then the RBridge or pseudonode with
      the numerically higher IS-IS ID (LAN ID) keeps the nickname, or if
      there is a tie in priority,* the RBridge with the numerically
      higher IS-IS System ID keeps the nickname, and the other RBridge
      MUST select a new nickname.  This can require an RBridge with a
      configured nickname to select a replacement nickname.