The MPLS WG Archive

["Ashwin C. Prabhu" <Ashwinp@in.huawei.com>]

Title: Doubt in draft-ietf-mpls-te-mib-07.txt MIB

 

Hello Abhay

 

     Thanks for your reply.

   

     But still i am not clear.

 

    There is one more entry in the tunnel table. fastReroute under the mplsTunnelSessionAttributes

    as follows

 

-----------------------------------------------------------------------------------------------------------------------------------------------

    mplsTunnelSessionAttributes OBJECT-TYPE
   SYNTAX      BITS {
                  fastReroute (0),
                  mergingPermitted (1),
                  isPersistent (2),
                  isPinned (3),
                  recordRoute(4)
                 }
   MAX-ACCESS    read-create
   STATUS        current
   DESCRIPTION
        "This bitmask indicates optional session values for
          this tunnel. The following describes these
          bitfields:
       
        fastRerouteThis flag indicates that the any tunnel
          hop may choose to reroute this tunnel without
          tearing it down.  This flag permits transit routers
          to use a local repair mechanism which may result in
          violation of the explicit routing of this tunnel.
          When a fault is detected on an adjacent downstream
          link or node, a transit router can reroute traffic
          for fast service restoration.
        
   REFERENCE
        "1. RSVP-TE: Extensions to RSVP for LSP Tunnels,
          Awduche et al, Internet Draft <draft-ietf-mpls-rsvp-
          lsp-tunnel-07.txt>, August 2000."
   DEFVAL        { 0 }
   ::= { mplsTunnelEntry 13 }

 

 I think the flag you were talking about is the above one and not the mplsTunnelLocalProtectInUse.

 Please tell me if i am wrong.

 I am still not clear about mplsTunnelLocalProtectInUse flag what it is ment for ? According to my

 understanding this flag shold be set only when the local protection is in use ? And if this is what is

 the purpose then it should be read-only and not read-create.

 

Best Regds,

Ashwin

 

-----Original Message-----
From: abhay [mailto:abhay@multitech.co.in]
Sent: Tuesday, October 16, 2001 9:48 AM
To: Ashwin C. Prabhu; mpls-ops@mplsrc.com; mpls@UU.NET
Subject: Re: Doubt in draft-ietf-mpls-te-mib-07.txt MIB

Ashwin,

           mplsTunnelLocalProtectInUse,is usually used by the administrator to view if the primary path is protected.

 

          1) When we enable a primary path to have disjoint local protection path,the primary path has its mplsTunnelLocal

           ProtectInUse filled when we create the path and not when the link in the path fails.

 

           2)It is also can be a way to telling the MPLS Management(ref the recent draft on MPLS Management) running on the

              router to know that the primary path is fast-reroute enabled and this router if required should participate in setting up

              local repair paths.

 

          That explains the read-create attribute of the variable.

 

          Hope this helps,

          Regards,

          Abhay

----- Original Message -----

From: Ashwin C. Prabhu

To: mpls-ops@mplsrc.com ; mpls@UU.NET

Sent: Monday, October 15, 2001 7:21 PM

Subject: Doubt in draft-ietf-mpls-te-mib-07.txt MIB

Hello

 In the  draft-ietf-mpls-te-mib-07.txt tunnel table
 the Local protection is defined as

mplsTunnelLocalProtectInUse  OBJECT-TYPE
   SYNTAX        TruthValue
   MAX-ACCESS    read-create
   STATUS        current
   DESCRIPTION
        "Indicates that the local repair mechanism is in use
          to maintain this tunnel (usually in the face of an
          outage of the link it was previously routed over)."
   ::= { mplsTunnelEntry 15 }

 Shouldn't this be read-only variable as the fast reroute is enabled only
 when the link is failed and the local protection is in use flag will be set?

 
Ashwin