EIGRP wide metric

[adfsdafs adsfafds]

If a router supports wide metric, does it necessarily use wide metric if the EIGRP process is in named mode?

R1#show eigrp protocols
EIGRP-IPv4 VR(init-eigrp) Address-Family Protocol for AS(100)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0 K6=0
Metric rib-scale 128
Metric version 64bit

How does it handle backwards compatibility? network with mixed named mode and classic mode EIGRP processes

Is there a quick way to tell if a neighbor is using wide metric? 

Thanks.

[milan.kulik]

Hi,

I guess the router should detect the neighbor is not using K6, i.e., running the classic mode EIGRP?

And then to talk to it using the classic metric?

As written here:

http://brbccie.blogspot.cz/2014/08/eigrp-enhancements.html

"EIGRP named mode automatically uses wide metrics when speaking to another EIGRP named mode process. No additional configuration is necessary, this is automatic. So if it's speaking to a traditional EIGRP process, it uses the old calculations."

Best regards,

Milan

[Mark Malone]

Is there a quick way to tell if a neighbor is using wide metric?

when you check the show ip eigrp topology table for a route/network the calculation will be in pico seconds and not microseconds

You should try use one mode or the other not both reason behind it is the metrics will be sent on classic and new mode until a decision is made by each peer what to use so your increasing resource use if not required in bandwidth when there's no requirement oif you already know what's supported , any redistribution pe/ce will all use classic. like Milan said classic - new the classic will win and the peer will revert to classic mode to be compatible

v8 and above eigrp supports wide metrics , show eigrp plugin will give you the version your device is on