two pool ratio configuration?

Hi there,

 

 

You could do this with an iRule, but I think it would be easier and more efficient to use ratio load balancing in a single pool. You could set the ratio on the members you want to receive 80% of traffic to 4 and the ratio of members you want to receive 20% to 1. This would also allow you to use a single persistence profile to ensure requests from the same client are sent to the same pool member.

 

 

You can get more information on ratio load balancing in the LTM config guide for your version:

 

 

 

LTM 9.3 Config Guide

 

https://support.f5.com/kb/en-us/products/big-ip_ltm/manuals/product/bigip9_3config/BIG_IP_LTM_9_3_Config_Guide-05-1.html

 

 

Ratio (member) and Ratio (node)

 

The BIG-IP system distributes connections among machines according to ratio weights that you define, where the number of connections that each machine receives over time is proportionate to a ratio weight you define for each machine. These are static load balancing methods, basing distribution on static user-assigned ratio weights that are proportional to the capacity of the servers. Regarding Ratio load balancing:

 

 

Load balancing calculations may be localized to each pool (member-based calculation) or they may apply to all pools of which a server is a member (node-based calculation). This distinction is especially important with the Ratio method; with the Ratio (member) method, the actual ratio weight is a member setting in the pool definition, whereas with the Ratio (node) method, the ratio weight is a setting of the node.

 

 

The default ratio setting for any node is 1. If you use the Ratio (as opposed to Ratio (member) load balancing method, you must set a ratio other than 1 for at least one node in the configuration. If you do not change at least one ratio setting, the load balancing method has the same effect as the Round Robin load balancing method.

 

 

Warning: If you set the load balancing method to Ratio (node), as opposed to Ratio (Member), you must define a ratio setting for each node.

 

 

 

 

Aaron

Thank you Aaron.

 

 

We need to have two pool ratio lb for certain reasons. I was provided the following irule but it is not working, any ideas?

 

 

 

•Pool ratio configuration

 

As discussed, the best way to do this is with a pool populated with two "dummy" IP addresses. These addresses can be used within an iRule as tokens to select the appropriate destination pool. This allows us to use BIG-IPs native LB engine, and is very lightweight and supportable. Configuration example below.

 

 

Pool ratio configuration

 

 

virtual dual_pool_mail_vip {

 

pool dual_pool_mail_pool

 

destination 10.1.2.3:smtp

 

ip protocol tcp

 

rules dual_pool_mail_rule

 

}

 

pool dual_pool_mail_pool {

 

lb method member ratio

 

members

 

1.2.3.4:smtp

 

ratio 80

 

5.6.7.8:smtp

 

ratio 20

 

}

 

rule dual_pool_mail_rule {

 

when LB_SELECTED {

 

LB::reselect

 

pool dual_pool_mail_[LB::server addr]

 

}

 

}

 

pool dual_pool_mail_1.2.3.4 {

 

members

 

1.0.0.1:smtp

 

1.0.0.2:smtp

 

1.0.0.3:smtp

 

1.0.0.4:smtp

 

1.0.0.5:smtp

 

}

 

pool dual_pool_mail_5.6.7.8 {

 

members

 

2.0.0.1:smtp

 

2.0.0.2:smtp

 

 

}

 

That's a novel approach. Out of curiosity, where did you get it from?

 

 

When you say it's not working, what do you see when you test it? Do you see the request making it to the VIP, any errors in /var/log/ltm, ARP for the dummy IP's or the actual server IP's, the request being sent to the actual server IP's, etc?

 

 

Aaron

Is this solution still valid, I tried implementing it and for some reason LB::select picks only one of the dummy nodes and seems to ignore the ratios I defined.

 

-- Danny