WAAS - NME Implementaion confirmation question

Paul Pinto · ‎11-18-2008

Hi,

I would just like to confirm if there is any reason why using a /31 mask would not work with an NME using WCCP? If not, what the reason would be.

I don't believe this would work with the Appliance on it's own VLAN, probably at least a /29??

Thanks in advance.

Paul Pinto · ‎11-18-2008

Hi again,

I hope my query is not to ambiguous or sounds trivial.

I would just like to confirm it.

Thanks again.

ropethic · ‎11-18-2008

You will need a least a /30

With a /30 you get 2 host addresses.

So lets say network 0, host 1 and 2. x.x.x.1 for

the gateway, 2 for the NME, WCCP router list x.x.x.1,

Here is a sample config

R2821-edge#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

R2821-edge(config)#int integrated-Service-Engine 1/0

R2821-edge(config-if)#ip address 10.10.100.1 255.255.255.252

R2821-edge(config-if)#service-module ip address 10.10.100.2 255.255.255.252

R2821-edge(config-if)#service-module ip default-gateway 10.10.100.1

R2821-edge(config-if)#ip wccp redirect exclude in

R2821-edge(config-if)#exit

R2821-edge(config)#end

R2821-edge#copy running-config startup-config

Paul Pinto · ‎11-18-2008

Hi Robert,

Thanks again for the prompt response.

I am OK with the general required config, it's the mask I'm querying. I'm being told the /31 would be OK. So, below is the intendended config in question (using your example host range of .1 and .2):

R2821-edge(config)#int integrated-Service-Engine 1/0

R2821-edge(config-if)#ip address 10.10.100.1 255.255.255.254

R2821-edge(config-if)#service-module ip address 10.10.100.2 255.255.255.254

R2821-edge(config-if)#service-module ip default-gateway 10.10.100.1

This works with Point-2-Point links and the likes, but with the NME? This is where my query lies.

Thanks again for the assistance.

ropethic · ‎11-18-2008

with a /31 you only get 1 subnet address and that would not allow for the NME WAE and gateway to be on the same network.

if int engine is 10.10.100.1 whta will you use for an address for NME service module?

i guess you could /31 with 10.10.100.2 but will need a default route on the NME to get to the default gateway or simply have a L2 connection to the between the wae and integrated service engine.

It would probably work, but not sure why you would not want to use a minum of two address

You need an IP on the NME for CMS registration back to CM. It has always been Cisco best practice to put engine and module on same net

Paul Pinto · ‎11-18-2008

Hi Robert,

Thanks again for the promt reply,

Like you say, there are the two adresses, and it would probbaly work, but it's not best practice, so I was just looking for some confirmation on the best practices which you have provided.

Will let you know the outcome soon.

ropethic · ‎11-18-2008

http://www.cisco.com/cgi-bin/Support/IpSubnet/home.pl

URL for subnet calculator

/31 will only give you one address.

As long as the router can see the nme in wccp group, it should be fine.

All routers with ip wccp 61 & 62 will be part of the same group. With the NME and Appliance, you just need to provide the wccp router list.

I will try in my lab also.

when done, do a show wccp routers on wae

if router shows up then you are fine. WCCP will use the highest IP address of an interface to identify itseld to WAE

Paul Pinto · ‎11-21-2008

Hi,

Were you able to try this in the lab yet?

Thanks again for the prompt responses.