I am trying to configure ospf bfd between R1 AND R2 .
The bfd interval command crashing my router.
It seems you are using dynamips..
Share the IOS version that is causing problems
Cisco IOS Software, 7200 Software (C7200-SPSERVICESK9-M), Version 12.2(33)SRE2,
Dynamips can't cope with sub-second protocols like OSPF BFD and OSPF Fast Hello.
What is worth trying is to set the BFD interval to the maximum value:
R9(config-if)#bfd interval 999 min_rx 999 multiplier 3
I tried this 999 figure on my dynamips still it;s hanging./
I think you just can't do the bfd on the dynamips, since the bfd is more like a hardware function than a soft one.
The ospf fast hello is ok, just will cost you a lot of cpu resource .
Although supported by the 7200, I don't think dynamips supports or work well with BFD, have been unable to get it working either.
Just my 2 cents.