About distributing the default route with OSPF

[Hirotaka Kato]

Hi All,

It is necessary to switch the default gateway in the OSPF environment.

The scale is about 30 routers.

1)Enter

no default-information originate

for devices that have already distributed the default route.

2)Introduce

default-information originate

to new equipment.

*1) and 2) work time is about 1 minite.

Will the default route be distributed immediately after the settings are submitted?

Also,how long will it take to disconnect the communication?

I don't want to interrupt communication for more than 2 minutes.

Best regards,

[Georg Pauwen · Accepted solution]

Hello,

I just tested this, on a smaller network, but the default route shows up in less than 1 second. 

[Hirotaka Kato]

Hello,Georg

Thanks for the reply.

[MHM Cisco World]

One suggest "test it by lab with counties ping"
can you play with metric, form old to new, 
this make control plane recalculate the new default route and data plane still use the default route in RIB.
i.e. metric for new better that metric of OLD one and hence the OSPF do recalculate and still RIB is use OLD one.