Re: OSPF Virtual-links and tunnels

Hi Greg,

I think the only other time you may consider using a tunnel is if the lab
says "Don't use Virtual-Links" and you need to have a contiguous OSPF
domain.

You can extend virtual-links by adding a new one onto the end providing the
transit area isn't nssa or stub (in that case tunnels are the way to go)

Provided the area type supports it, you could build a VL between SW2 and
SW4, since the first virtual link extends area 0 to this device (you can see
this when you show ip ospf int brief) which enables you to build chains of
virtual-links where required.

I believe that you could have also put that tunnel directly into area 0 as
well.

Cheers,
Adam

On Thu, Oct 14, 2010 at 3:15 AM, Grzegorz Cegielski <
grzegorz.cegielski_at_klonex.com.pl> wrote:

> Hi All,
>
> I have a question regarding the virtual link and tunnels. When we have to
> use tunnel beside those listed here?
>
> http://www.cisco.com/en/US/tech/tk365/technologies_configuration_example0918
> 6a00801ec9ee.shtml#using<http://www.cisco.com/en/US/tech/tk365/technologies_configuration_example0918%0A6a00801ec9ee.shtml#using>
>
> I have made a setup as below:
>
> R6--A0--SW1--A0--R3--A345--R5--A345--SW2--A24--SW4--A234-SW3--A234--R2
>
> A - abbreviation of word Area
>
> In this setup to have full connectivity I had to:
> 1. Setup a virtual link between R3 and SW2 using Area 345 as Transit Area.
> 2. Setup a tunnel between SW2 and SW4 and put it into the Area 234.
>
> Is there any other solution in such scenario to have full connectivity
> between R6 and R2? For example using only virtual-links?
>
> Regs,
> --
> -=[ Greg Cegielski ]=-
>
>
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Received on Thu Oct 14 2010 - 09:07:20 ART