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Cisco Router T1 Load balancing

I am having a hard time getting my cisco 3745 to load balance traffic. I have a 2 port WIC with 2 T1's and its always picking the first route every time even though it maxes out at 255TX and will not send any traffic to the second T1. Please let me know what you think or what I can try. The route looks like:

S 168.183.0.0/16 [1/0] via 168.183.138.129
[1/0] via 168.183.138.125

IOS Version:
Cisco Internetwork Operating System Software
IOS (tm) 3700 Software (C3745-JK9O3S-M), Version 12.3(5a), RELEASE SOFTWARE (fc1)
Copyright (c) 1986-2003 by cisco Systems, Inc.
Compiled Tue 25-Nov-03 01:28 by kellythw
Image text-base: 0x60008AF4, data-base: 0x620D2000

ROM: System Bootstrap, Version 12.2(8r)T2, RELEASE SOFTWARE (fc1)

SLC_3745 uptime is 2 hours, 51 minutes
System returned to ROM by reload at 12:11:27 UTC Wed Jun 6 2007
System image file is "flash:c3745-jk9o3s-mz.123-5a.bin"

cisco 3745 (R7000) processor (revision 2.0) with 249856K/12288K bytes of memory.
Processor board ID JMX0737L2V6
R7000 CPU at 350MHz, Implementation 39, Rev 3.3, 256KB L2, 2048KB L3 Cache
Bridging software.
X.25 software, Version 3.0.0.
SuperLAT software (copyright 1990 by Meridian Technology Corp).
TN3270 Emulation software.
Primary Rate ISDN software, Version 1.1.
2 FastEthernet/IEEE 802.3 interface(s)
5 Serial network interface(s)
4 Channelized T1/PRI port(s)
1 Subrate T3/E3 ports(s)
DRAM configuration is 64 bits wide with parity disabled.
151K bytes of non-volatile configuration memory.
125184K bytes of ATA System CompactFlash (Read/Write)

Configuration register is 0x2102

benhanson

create a multilink interface, assign it a ppp multilink group, associate the two T1's with the same Multilink group. You may have to create a policy-map first, but this is quite simple as well.

http://www.cisco.com/en/US/products/ps6350/products_configuration_guide_chapter09186a00804a40f9.html#wp1027188

benhanson

Here's an example from a working multilink setup.

interface Multilink1
description My MultiLink T1
ip address 192.168.1.5 255.255.255.0
service-policy output QOS-to-T1
ppp multilink
ppp multilink group 1

class-map match-all VOIP-Control
match access-group 101
class-map match-all VOIP-RTP
match access-group 100
!
!
policy-map QOS-to-T1
class VOIP-RTP
priority 600
class VOIP-Control
bandwidth 200
class class-default
fair-queue
policy-map L3-to-L2-VOIP
class VOIP-RTP
set cos 5
class VOIP-Control
set cos 3

interface Serial2/0
no ip address
encapsulation ppp
ppp multilink
ppp multilink group 1
!
interface Serial2/1
no ip address
encapsulation ppp
ppp multilink
ppp multilink group 1

ykamp

I think that if you need load balancing you must also contact you ISP. The multiling must be on both sides

benhanson

Right, it must be on both sides. I was assuming these were T1's between two sites, not internet content T1's from you to your ISP.

manticGuru

ASKER

Since they are frame relay circuits I dont think I can use the PPP command. Listed below are the configs of each one. What do you think?

interface Serial0/1:0
ip address x.x.x.130 255.255.255.252
encapsulation frame-relay IETF
frame-relay interface-dlci 149
frame-relay lmi-type cisco

interface Serial0/1:0
ip address x.x.x.126 255.255.255.252
encapsulation frame-relay IETF
frame-relay interface-dlci 149
frame-relay lmi-type cisco

benhanson

Do you control both ends, or are these ISP Content T1's?

ASKER CERTIFIED SOLUTION

benhanson

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manticGuru

ASKER

This is what I used and it worked. I worked with one of my engineers to get to this solution.

This is how I've always done it and had good luck. If the "ip load-sharing per-packet" command isn't available, CEF might be disabled

Under the frame relay subinterfaces (or physical interfaces if you're not using subs), add the following command:
ip load-sharing per-packet

Then add static routes on that router for each of our networks pointing to each circuit to get two equal cost routes to the same destination.

Example
ip route 168.183.x.x 255.255.0.0 "sub-interface" "next-hop IP"
ip route 168.183.x.x 255.255.0.0 "sub-interface" "next-hop IP"

SOLUTION

rburns50

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SOLUTION

soporific

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soporific

Sorry, didn't mean to duplicate. I missed those couple comments above.

soporific

"It is assumed that any participant not responding to this request is no longer interested in its final disposition."

Well I've never earned any points here yet, so I'm interested :P

benhanson

I suppose I'm still an interested party as well.

rburns50

I think my comment added value....but could care less about the points (just like to help)

benhanson

I think manticGuru's answer sounded best, I would split points 60(mant), 20(ben), 20(rburns), or 80, 10, 10.

rburns50

didn't he (manticGuru) ask the question???

benhanson

He did, I wasn't paying attention. After re-reading his comment, it sounds like he answered his own question and points should be refunded.

"This is what I used and it worked"