Re: Redistribute Static metric x x x x x Route-Map Static...HELP

Erick.Valle · ‎08-17-2010

Hello Everyone, I have been looking for some help on a specific issue that I am having but I can't seem to find the same senerio anywhere online...like that is strange! However, I have drawn a diagram and attached it to see if anyone can help me figure out the best way to do this. I need to modify the metric of a redistributed route in order for the CORE router to see it as the primary path. when the main frameRelay ckt has reestabished after an outage. When the ckt is down, it will take the wireless route, which is not running eigrp, it is base soley of static routes. There is a purpose to this because of cost. If not I would be runing eigrp everywhere. The problem is the switch loopback address that I am redistributing to the core with a meter of 1 1 1 1 1 at this time. I can get to it with no problem under normal conditions. when the frame goes down I can also get to it fine. But when the FrameRelay comes up the eigrp sees the wireless route as a better route and it stays there. It will not see the Frame Ckt as a better path. Please see diagram and let me know if I can make sense out of this for anyone.

Thanks in advance,

Erick

gatlin007 · ‎08-17-2010

Why not allow the switch loopback to be native to EIGRP so that it's considered an internal EIGRP route; admin distance 90. This way it will always look better than the external EIGRP route (admin distance 170) when it is available.

As an alternative if the static route is being redistributed on the wireless router change the redistributed metric to reflect the true circuit attributes at all points of redistribution.

The following from: http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a008009487e.shtml

Redistribution Configuration Syntax and Examples

IGRP and EIGRP

This output shows an IGRP/EIGRP router redistributing static, Open Shortest Path First (OSPF), RIP, and Intermediate System-to-Intermediate System (IS-IS) routes.

router igrp/eigrp 1 
network 131.108.0.0 
redistribute static
redistribute ospf 1 
redistribute rip 
redistribute isis 
default-metric 10000 100 255 1 1500

IGRP and EIGRP need five metrics when redistributing other protocols: bandwidth, delay, reliability, load, and MTU, respectively. An example of IGRP metrics follows:

Metric	Value
bandwidth	In units of kilobits per second; 10000 for Ethernet
delay	In units of tens of microseconds; for Ethernet it is100 x 10 microseconds = 1 ms
reliability	255 for 100 percent reliability
load	Effective load on the link expressed as a number from 0 to 255 (255 is 100 percent loading)
MTU	Minimum MTU of the path; usually equals that for the Ethernet interface, which is 1500 bytes

Keep in mind that the by default EIGRP only evaluates bandwidth and delay.

The following from: http://www.cisco.com/en/US/tech/tk365/technologies_white_paper09186a0080094cb7.shtml#redis

EIGRP uses these scaled values to determine the total metric to the network:

metric = [K1 * bandwidth + (K2 * bandwidth) / (256 - load) + K3 * delay] * [K5 / (reliability + K4)]

Note: These K values should be used after careful planning. Mismatched K values prevent a neighbor relationship from being built, which can cause your network to fail to converge.

Note: If K5 = 0, the formula reduces to Metric = [k1 * bandwidth + (k2 * bandwidth)/(256 - load) + k3 * delay].

The default values for K are:

K1 = 1
K2 = 0
K3 = 1
K4 = 0
K5 = 0

For default behavior, you can simplify the formula as follows:

metric = bandwidth + delay

Erick.Valle · ‎08-18-2010

Forgive me for the dump question I'm about to ask, as I am new to routing and switching..I usually focus more on the security side of things. However, Thank you for your reply, but how would I go about allowing the switch loopback to be native to EIGRP? I have looked around but I am still at a stand still. YOur advise is greatly appreciated.

Erick

gatlin007 · ‎08-18-2010

Erick,

There are no bad questions. I remember asking my old boss what SSH was.

Add the switch loopback address to EIGRP in the form of a network statement. This makes it internal or native to EIGRP. Something like the following:

router eigrp XXXX

network 192.168.113.13 0.0.0.0

exit

This should cause all the routers receiving this route to install it in the route table with an administrative distance of 90 making it more attractive than the redistributed route on the wireless router (external EIGRP route) with and administrative distance of 170.

Chris

Erick.Valle · ‎08-24-2010

Hey Chris,

I tried your suggestion of putting the switch Lpbk add as a network into eigrp but the loopback address of the switch is not being seen by the core router in eigrp at all. The only way the core router sees the loopback address is by configuring the following

(1) a static route= ip route 192.133.190.13 255.255.255.255 192.168.191.7

(2) Extended IP access list ALLOWED_STATICS

permit ip host 192.133.190.13 host 255.255.255.255

(3) router rigrp xxx

redistribute static metric 1 1 1 1 1 route-map STATIC->EIGRP

Once the core router is aware of the loopback address in it routing table it shows up with an AD as 170 as external, and so the wireless backup route is used instead of the primary circuit.

Core#sh ip ro 192.133.190.13
Routing entry for 10.133.190.13/32
Known via "eigrp 100", distance 170, metric 2560512512, type external
Redistributing via eigrp 100
Last update from 155.109.80.14 on Vlan80, 1d18h ago
Routing Descriptor Blocks:
* xx.xx.xx.xx(Core), from Core, 1d18h ago, via Vlanxx
      Route metric is 2560512512, traffic share count is 1
      Total delay is 20020 microseconds, minimum bandwidth is 1 Kbit
      Reliability 1/255, minimum MTU 1 bytes
      Loading 5/255, Hops 2

Route via the Wireless router:

************************************

Core#sh ip ro 192.133.190.13
Routing entry for 192.133.190.13/32
Known via "eigrp 100", distance 90, metric 268800256, type internal
Redistributing via eigrp 100
Last update from xx.xx.xx.xx(Wireless) on Vlan80, 00:00:22 ago
Routing Descriptor Blocks:
* xx.xx.xx.xx(Wireless), from xx.xx.xx.xx(Wireless), 00:00:22 ago, via Vlan80
      Route metric is 268800256, traffic share count is 1
      Total delay is 500010 microseconds, minimum bandwidth is 10 Kbit
      Reliability 255/255, minimum MTU 1472 bytes
      Loading 2/255, Hops 1

Any suggestion and question are welcome.

Erick

Jeremy Buck · ‎08-24-2010

Hey Erick,

Are you running EIGRP between the switch & router in the yellow box at the lower right corner of your diagram?

Once you include the network statement on the switch with the loopback, you should immediately see an AD 90 route for that network advertised to the adjacent router and accross the frame relay link. All routers minus that of the wireless router should prefer the AD 90 route.

Can you paste your EIGRP configs for the 2 routers and the switch?

Thanks,

Jeremy

EPHRAIM MANI · ‎08-24-2010

Thanks Chris your post is informative.

Erick.Valle · ‎08-25-2010

Hey Jeremy, I am not running EIGRP on the remote switch, it only has layer2. However I think I have figured out my problem. The wireless router is also redistributing the static route to the CORE eigrp, but they are being redistributed with an AD of 90/Internal, as apoose to the normal behavior if redistributed static routes that should be with an AD of 170 and consider external to eigrp. As is the case from the route router, So in this case it seems that the IOS that I am running on the wireless router has a bug, or something process calculation is wack out in the router because the default behavior to eigrp on the redistributed static should be external with AD-170,unless the AD has been changes and in this case it has not. So for now the reason why the eigrp is preferring the wireless route instead of the frame relay ckt is because the core is seem a AD of 90 via the wireless and AD of 170 via the frame. Thanks for all your input guys. If anyone has any question of reason to think that I am in the wrong, please advise..

Regards,

Erick