Router Load Balance

What Is An Affordable, Multiple WAN Input, Load Balancing...

New postby Dierdre » 25 Oct 2012, 19:53

What is an affordable, multiple WAN input, load balancing router?

We have a medium sized office and our single T1 connection gets maxed out from time to time. I'm looking for an affordable upgrade solution. Ideally I would use a router that could take our T1 connection and an additional WAN connection (either cable, DSL, or another T1). I'm trying to figure out if there exists an affordable router, that's not hard to configure, that can do this.
With a Cisco 1841 can I use a T1 as one WAN connection and DSL or Business Cable as the other WAN connection? Does it depend on the broadband providers or can the 1841 handle any/most broadband connections?
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New postby Margene » 25 Oct 2012, 19:53

If you going for WAN, go for a great product. Look for some Cisco routers, like the 2810 or basically 2800 series ones. I use the predecessors of 2800 series router, i.e the 2600 series for WAN connectivity. They are tremendous !! Take a look at some Nortel and D-Link routers as well (I hate D-Link - highly unreliable but very cheap!!)
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Trying to load balance a cisco 1720 router w/ 2 T1's...

New postby Clemmie » 25 Oct 2012, 19:53

Trying to load balance a cisco 1720 router w/ 2 T1's running to it?

I have a 7200vxr supplying 2 T1's to a 1720 router. I have them load balancing, and the graphs show this. But when the customer goes to do a speed test, it shows only 1.5mps. This i believe is due to it working as a per-destination style, instead of per-packet. Everywhere i read tells me to use 'IP cef', but there is no recognition of IP cef anywhere on the 1720 router.

Here is the ver for the 1700 series.

IOS (tm) C1700 Software (C1700-Y-M), Version 12.1(5)T12, RELEASE SOFTWARE (fc1)

Please any help would be great. Do they just need to upgrade their IOS? It seems like IP cef was introduced before 12.1, but i can't find anything to confirm or deny that it should be on there. Thanks much. Please ask me for any more details you would need. Thanks again
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New postby Lincoln » 25 Oct 2012, 19:53

Sorry, I don't have any direct experience with your problem.
It appears CEF is supported in your IOS version. What happens when you enter 'ip cef' in config mode [ router-1720#(config) ip cef ]? Does it show up in the running config? Do you get anything when entering the command 'sh ip cef summary' in enable mode?
Be aware the 12.1(T) IOS train is no longer updated and is subject to multiple vulnerabilities, so an upgrade is recommended.
If you enable CEF and then create an access list that uses the log keyword, the packets that match the access list are not CEF switched. They are fast switched. Logging disables CEF.
When performing a 'speed test', what is the destination IP, and is the routing distance/cost from the 1720 to the destination IP the same over both connections?
From the link shown below, it appears you should issue the 'no ip route-cache' command on the ethernet interface of the 1720. Note the warning that this may crash your router.
You may also need to use these commands: 'no ip load-sharing per-destination' and 'ip load-sharing per-packet' on applicable interfaces.
If you use a VPN connection across the T1's and have the VPN daughterboard in the 1720, you may suffer severe performance loss if you enable CEF on a newer IOS version.
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Can someone give me the basic configuration steps to load...

New postby Terrilyn » 25 Oct 2012, 19:53

Can someone give me the basic configuration steps to load balance two T1's? It is on a 1700 series router.
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New postby Alaina » 25 Oct 2012, 19:53

If you have 2 T1s coming into your 1700 series router, they should load balance automatically. The maximum-paths setting is 4 paths by default with a maximum of 6 paths. So assuming the routing protocol you're using gives two equal cost paths (one over each T1) then the router will automatically load balance these. You'll also want to look at if your want to do per-packet or per-destination load balancing, which can be accomplished with the interface commands "no ip route-cache" and "ip route-cache" respectively. If the paths are NOT equal cost, then you would need to run IGRP or EIGRP and configure the variance setting to allow unequal cost path load balancing. Also check out the design technote (link below) on IP routing load balancing.
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Load Balancing Router and DSL Question for Streaming Video.?

New postby Mai » 25 Oct 2012, 19:53

Said name customer has debit system (POS) on a DSL line with a dynamic IP of course. He wants to remote his DVR to view his shady employees while home. 4 cameras at 380x420 res I estimate need at least 2mbs up to stream decently. He gets 1.5 down and 1 up on his DSL. If we add a second DSL line with a static IP for the DVR, could I then install a load balancing router to double his upload speed? So I'd have the first dynamic ip modem going to a switch, the POS/debit system plugged into that switch, that switch going to the load balancing router, and also the second DSL line going to that load balancing router. Will this all work and anyone recommend a good load balancing router if my theory is in fact correct? Thanks for any help as I'm not familiar with load balancing routers.
Do you think I'll get 2 to 2.5mbs up to the DVR like this?
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New postby Ethyl » 25 Oct 2012, 19:53

You can't COMBINE the lines you will only get the speed of one line or the other!

You might check and see if the provider offers higher speed. Otherwise, you will have to have the ISP "BOND" the two lines so that you have only 1 IP which will then deliver the increased speed.

Without a "single" line (or two lines bound together), you will get TWO lines which can either fail over or load balance but not combine.

PS - I have a customer who views his DVR over a standard line without issues - its not "smooth" but he can indeed check any camera or view the four - they are just a little slow in updating.
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How to configure load balancing on cisco 1811 router on...

New postby Gino » 25 Oct 2012, 19:53

How to configure load balancing on cisco 1811 router on unequal links with local area network behind nat? How to configure load balancing on cisco 1811 router on unequal links with local area network behind nat?
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New postby Jane » 25 Oct 2012, 19:53

To properly answer this, we will need more information - particularly what routing protocol you are using (some support unequal cost load-sharing, some do not) and what the intended result is (outbound load-share, inbound load share, both, etc.).
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I am having two routers and two links termineted on the...

New postby Linh » 25 Oct 2012, 19:53

I am having two routers and two links termineted on the routers respectively. How shouls i load balance traffi

I am having two routers with single ISP connection on both. How could I load balance traffic between these two routers?
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Give suggestions for low cost load balancing routers with...

New postby Jermaine » 25 Oct 2012, 19:53

Give suggestions for low cost load balancing routers with 2 or more WAN ports?

Want to take multiple internet connections and use them on the network as one fast internet connection.
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New postby Alysa » 25 Oct 2012, 19:53

Buy a Cisco PIX with multiple WAN ports and it will load balance for your.


With a cisco 3700 router and a 2950 port switch I have been able to NAT LAN connections to 4 cable modems. Plug your cable modems in the 2950 ports and put each one on a diffrent VLAN, create an ISL or Dot1Q trunk from the switch to the router. Create virtual sub interfaces on the link from the switch and apply each sub interface one of the VLANS from the switch. So if you have 3 cable modems put them on VLAN 10, 20, 30. Then trunk VLAN 10, 20, 30 to the router and create FastEthernet0/0.10, FastEthernet0/0.20, FastEthernet0/0.30. For each subinterface have them aquire their IP address via DHCP. Apply an "ip nat outside" to each subinterface. For the inside interface apply and ip nat inside. Build access-lists consisting of the machines you want on each cable modem. So build:
access-list 110 permit ip host x.x.x.x
access-list 120 permit ip host x.x.x.x
access-list 130 permit ip host x.x.x.x
You can put multiple ip address or subnets on each access list. Finally build you global nat statement.

ip nat source-list 110 interface fastEthernet0/0.10 overload
ip nat source-list 120 interface fastEthernet0/0.20 overload
ip nat source-list 130 interface fastEthernet0/0.30 overload

So every host in access list 110 will go out to VLAN 10 on the outside switch which will then put the information on that cable modem.

This is a clunky way to do NAT and it's not really load balancing I would just research a cisco PIX
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