Santosh,
Just an an answer to 1.
Thus, I read "an LSA" as a Grace LSA as an
example..
Within "Router X recieves an LSA"...
Grace LSAs are Opaque LSAs and Opaque capability
is first required for GR. Secondly, then the
understanding of what a Grace-LSA is, and then
third the willingness to respond to a recieved
Grace-LSA.
Mitchell Erblich
-----------------
Santosh P K wrote:
>
> Hi all,
> I have couple of doubt in graceful restart for ospf.
>
> 1. Router X receives an LSA that is inconsistent with
its pre-
> restart router-LSA. For example, X receives a
router-LSA
> originated by router Y that does not contain a
link to X, even
> though X's pre-start router-LSA did contain a
link to Y. This
> indicates that either a) Y does not support
graceful restart,
> b) Y never received the grace-LSA or c) Y has
terminated its
> helper mode for some reason (Section 3.2).
>
> Why is it really required to validate the router LSA?
> In all the above three cases mentioned the restarting
router can come
> to know about inconsistency in hello packet itself, as the
hello
> received by that restarting router from its previously
adjacent
> neighbor would contain a one-way.
>
> 2 Seciont 2 point 2
> The restarting router runs its OSPF routing
calculations, as
> specified in Section 16 of [1]. This is
necessary to return
> any OSPF virtual links to operation. However,
the restarting
> router does *not* install OSPF routes into the
system's
> forwarding table(s) and relies on the forwarding
entries that
> it installed prior to the restart.
>
> At wht point of time I need to run SPF when the router
comes up?
> Because after adjacency is formaed the restarting router
exits
> graceful restart and anyways at this point it calculates
SPF and
> update forwarding table.
>
> Thanks and regards
> Santosh P K
>
> _______________________________________________
> OSPF mailing list
> [email protected]
> https://www1.ietf.org/mailman/listinfo/ospf
Santosh P K wrote:
>
> Hi all,
> I have couple of doubt in graceful restart for ospf.
>
> 1. Router X receives an LSA that is inconsistent with its pre-
> restart router-LSA. For example, X receives a router-LSA
> originated by router Y that does not contain a link to X, even
> though X's pre-start router-LSA did contain a link to Y. This
> indicates that either a) Y does not support graceful restart,
> b) Y never received the grace-LSA or c) Y has terminated its
> helper mode for some reason (Section 3.2).
>
> Why is it really required to validate the router LSA?
> In all the above three cases mentioned the restarting router can come
> to know about inconsistency in hello packet itself, as the hello
> received by that restarting router from its previously adjacent
> neighbor would contain a one-way.
>
> 2 Seciont 2 point 2
> The restarting router runs its OSPF routing calculations, as
> specified in Section 16 of [1]. This is necessary to return
> any OSPF virtual links to operation. However, the restarting
> router does *not* install OSPF routes into the system's
> forwarding table(s) and relies on the forwarding entries that
> it installed prior to the restart.
>
> At wht point of time I need to run SPF when the router comes up?
> Because after adjacency is formaed the restarting router exits
> graceful restart and anyways at this point it calculates SPF and
> update forwarding table.
>
> Thanks and regards
> Santosh P K
>
> _______________________________________________
> OSPF mailing list
> [email protected]
> https://www1.ietf.org/mailman/listinfo/ospf
_______________________________________________
OSPF mailing list
[email protected]
https://www1.ietf.org/mailman/listinfo/ospf
