Abhay D.S.,
Actually it is just a bit more
complicated.
With OSPF, we should start with a case
of two routers.
How does the restarting router know
that the restart is done and how does
the other router know that the restart
is done?
The restarting router can determine
whether NSF and restart is done. Whether
restart required a a standard resync of
the LSDB is almost irrelevant.
So, the question is why must Gracefull
be successful? It basicly just "reduces"
overhead while NOT distrupting forwarding.
Thus, It is done when it re-starts sending HELLOs
and re-extablishes full adjs from the perspective
of the 2nd router. The hellos are the aliveness
criteria from my earlier post.
` So, you MIGHT want to track the nbr FSM
if you have access to the OSPF source code.
Mitchell Erblich
----------------
"Abhay D.S" wrote:
>
> Mitchell,
>
> 2) Their is no GUARANTEE that any Restart will
> be sucessful, that the LSDB will be stable and/or
> that helper(s) exist.
>
> I wanted an automated and deterministic number 2.
>
> Any ideas or any attempts in the direction of 2 ?
>
> With Regards,
> Abhay
>
> ----- Original Message -----
> From: "Erblichs" <[EMAIL PROTECTED]>
> To: "Abhay D.S" <[EMAIL PROTECTED]>
> Cc: <[email protected]>
> Sent: Saturday, October 20, 2007 3:43 AM
> Subject: Re: [OSPF] Cascaded Graceful Restarts with NSF for OSPF
> protocolQuestion
>
> > Abhay D.S., et al,
> >
> > Their are multiple issues that need to be addressed
> > before you can even attempt to sucessfully perform
> > a cascade restart:
> >
> > 1) NSF is a patented process that is specific to
> > one well-known company.
> >
> > 2) Their is no GUARANTEE that any Restart will
> > be sucessful, that the LSDB will be stable and/or
> > that helper(s) exist.
> >
> > 3) It would be my initial expectation that
> > resumption of recieving "aliveness" from a
> > restarting router COULD be a passive method.
> >
> > Mitchell Erblich
> > -----------------
> >
> > "Abhay D.S" wrote:
> > >
> > > hi all,
> > >
> > > Suppose I am providing real-time transactions over IP in a
> > > non NSR environment(I dont invest much on getting a backup RP i.e).
> > >
> > > But I have NSF, owing to the ease of which OSPF can be used, I
> > > use OSPF to manage connections to WAN.
> > >
> > > And I have bought new I/0 modules which require a restart for
> > > all my routers for proper installation.
> > >
> > > Luckily, I have inservice upgrade on the boxes.
> > >
> > > Assuming that I am a new operator without any certifications under
> > > my belt, I dont have a beautiful NMS with colored buttons.
> > >
> > > But I must implement the new I/O cards and its features without
> disturbing
> > > the users who are using the network for routing transactions such as
> data
> > > backup over network or voice forwarding and other distributed
> applications
> > > running over TCP/IP using my network.
> > >
> > > I want to graceful restart all my routers one by one, called as cascaded
> > > re-starts, how can I make sure the transition is done seamlessly.
> > >
> > > I want the "this thing" to be automatic, since each router is graceful
> > > restarted
> > > and then then the next one is re-started and then the next one,
> > > automatically.
> > >
> > > I can write a script to do that, but I am not sure the forwarding will
> be
> > > safe,
> > > because it is difficult to control the network transient conditions.
> > >
> > > Any mechanism available ?.
> > >
> > > Thanks and Regards,
> > > Abhay
> > >
> > > _______________________________________________
> > > OSPF mailing list
> > > [email protected]
> > > https://www1.ietf.org/mailman/listinfo/ospf
_______________________________________________
OSPF mailing list
[email protected]
https://www1.ietf.org/mailman/listinfo/ospf
