cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
1290
Views
0
Helpful
9
Replies

Balancing 2 Router with ACE

vpetracca
Level 1
Level 1

Hi everybody...

A customer wants to loadbalance two router with an ACE 4710 !!

So basically ( i told him that he can do it in other way..) but ..nothing !!!

He wants to use a Loadbalancer !!!

I tested in my lab creating a similar network topology...( similar to Balance two firewalls).

But it's not necessary to have any mac-sticky enable and it doesn't matter about asimmetric routing !!

Which Predictor can let me loadbalance "per packet"  ?

In the bottom example

                   ROUTER-1 int gi 0/1 ( 2.2.2.1)

    WAN <------                                           <------- ACE 4710 --- Clients

                  ROUTER-2  int gi 0/1 ( 2.2.2.2) 

customer want ACE4710 to send a packet to ROUTER-1 and a packet to ROUTER-2 as routers were Rservers!!

The predictor should choose the best Router ( the one that has the less number of packets in on int gi 0/1)

I tried predictor least-loaded with an snmp probe on oid ifOctentin of the interface gi 0/1..

But it works in a strange way ( rservers became MAX-LOAD and the Serverfarm stop working) !!

Any ideas ?

Thanks to all will give me some help,advise,info !!

9 Replies 9

asharmav
Level 1
Level 1

Can you share the config of your probe and your serverfarm.

And also inyour case , i would suggest you to go with Predictor leastbandwidth.

Regards

Abijith

As soon as possible i'll send you the config !!

But any advise using least-bandwith ?

Let me explain...

I know that least-bandwith is ok for Long-time-connection ( as..downloading a video clip ).

But i think customer will check using this type of test (so i'm using pretty the same in my Lab) :

One Client ( six  same processes :  ping 1.1.1.4 -t -l 1500)  for an hour !!

                                               ROUTER-1 int gi 0/1 ( 2.2.2.1)

SERVER ( 1.1.1.4 )   <--- WAN                                              <------- ACE 4710 --- Client

                                               ROUTER-2  int gi 0/1 ( 2.2.2.2) 

So again ... Any good advise using predictor least-bandwith in this situation ?

Just curious, Is there any product DOES support load-balancing per packet?

acoolme

Hi Alex,

Load-balancing per packet is undesireable for most kinds of traffic, so, no, there are no products doing it.

Daniel

Daniel Arrondo Ostiz
Cisco Employee
Cisco Employee

Hi,

The ACE doesn't support load-balancing per packet, only per connection.

For this kind of setup, you will probably achieve the best results using the simple round-robin predictor, but you can also try "leastconn". The best approach would be configuring one of the predictors, and keep it running for a few days to see the load-balancing results it gives before making the decision whether to try a different one or not

Regards

Daniel

I'm trying now roundrobin !!!

But the result are not so good ..

Let me explain  :

1) One Client ( six  same processes :  ping 1.1.1.4 -t -l 1500)  for an hour !!

                                               ROUTER-1 int gi 0/1 ( 2.2.2.1)

SERVER ( 1.1.1.4 )   <--- WAN                                              <------- ACE 4710 --- Clients

                                               ROUTER-2  int gi 0/1 ( 2.2.2.2) 

2) Statistic after half an hour :

    ROUTER-1 int gi 0/1 pkt in   1600

    ROUTER-2 int gi 0/1 pkt in   17800

I know that each np works indipendentely..but..why so big differences ?

Good afternoon,

This kind of test is not a good approach. As with any other kinds of traffic, the ACE will establish a connection for the ICMP traffic and keep it open for some time, so, all the traffic will basically go through one of the routers.

If you want to do a better testing, I would recommend doing a lot of HTTP requests against a web server. You should see better load-balancing in that way.

Daniel

Ok Daniel...

Just to make the customer see the solution working in the Lab i'll use the scenario you tell me ( a lot of HTTP requests..).

Anyway can be better/useful to use parameter "use-same-np" ( serverfarm parameter) just during the demo to the customer ,without using "hw-module cde-same-port-hash (global conf parameter)" as it is advise in some release notes of ACE software ...

In other words can be useful this parameter ( using roundrobin predictor ) to have a better balance between the two router ?

 

Thanks and best regards

No, I would not touch any of these two parameters. The normal load-balancing should already be good enough to prove that the system is working as expected

Daniel

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: