[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Originating LSAs during OSPF graceful restart



Hi Acee

I agree with what you said, but it didn't help me completely so let me put
my question simple and straight-forward.

1. What is the restarting router supposed to summarize during database
exchange while forming an adjacency with a neighbor (helper or otherwise)? 

2. Is the behavior here any different when compared to normal OSPF bring up?

Thanks again
Ramesh

-----Original Message-----
From: Acee Lindem [mailto:acee at CISCO.COM]
Sent: Monday, February 06, 2006 10:47 AM
To: OSPF at PEACH.EASE.LSOFT.COM
Subject: Re: Originating LSAs during OSPF graceful restart


Hi Ramesh,

Kandula, Ramesh wrote:

>Hi Acee,
>
>Thanks for the reply.
>
>Are you saying that the restarting router should not summarize
>self-originated lsas (I mean pre-restart self originated lsas) during
>database exchange with a neighbor? 
>
No. I'm saying the restarting router will not originate new LSAs until 
exiting
graceful restart.

>If so, why is this required? I don't find
>any statement in RFC3623 which implies this? 
>
>Also, you said if a neighbor doesn't have a pre-restart lsa, the restarting
>router will send it. If there was an adjacency before restart with this
>neighbor, isn't the restarting router supposed to quit restart mode? 
>  
>
No. In fact, a router won't act as a helper router unless it previously 
had an adjacency with
the restarting router.

Thanks,
Acee

>thanks
>ramesh
>
>-----Original Message-----
>From: Acee Lindem [mailto:acee at CISCO.COM]
>Sent: Saturday, February 04, 2006 2:34 AM
>To: OSPF at PEACH.EASE.LSOFT.COM
>Subject: Re: Originating LSAs during OSPF graceful restart
>
>
>Hi Ramesh,
>
>Ramesh Kandula wrote:
>
>  
>
>>Hi All,
>>
>>Should the restarting routing summarize it's own lsas (self-originated) 
>>during adjaceny establishment? This can happen in the following scenario.
>>
>>Suppose there are 3 OSPF routers on a broadcast network and the DR 
>>restarts. When it establishes adjacency with the first neighbor, it will 
>>get its own lsas from it. Now while forming adjaceny with the second 
>>neighbor, should it summarize it's own lsas?
>> 
>>
>>    
>>
>No.
>
>  
>
>>If yes, then the neighbor will request for them and the restarting router 
>>will send these lsas. So does the RFC 3623 mean that the restarting router

>>should not originate "newer" instances of lsas of type 1,5 or 7? 
>> 
>>
>>    
>>
>If the neighbor doesn't already have them (and normally it will), the 
>restarting router will send its
>pre-restart LSAs. Don't confuse origination with sending an LSA during 
>the database exchange
>process.
>
>Hope this helps,
>Acee
>
>  
>
>>Thanks in advance
>>ramesh
>>
>> 
>>
>>    
>>
>
>  
>