Contact us if you are looking to Buy a Used BIGIP®.
NOTE: Expert BIGIP and 3DNS Consulting from DOESconsulting is now available!
Click here to discuss your BIG-IP®/3DNS® consulting needs!
About DOESConsulting's BIG-IP®, 3DNS®, and Globalsite® Consulting Service: *
DOESConsulting can help you get quickly started with your BIG/IP® set-up. We assist with configuration, administration, and maintenance. DOESConsulting has years of experience quickly implementing BIG/IP® solutions. In fact, we include free consulting services with every sale of Used BIGIPs® to help you get up and running quickly!
At DOESConsulting, we can help you optimize the performance of your load balacers. DOESConsulting works with both small companies and large to help your I.T. Department and staff quickly clean, optimize and implement. If your company lacks the skills to configure and implement BIG/IP®, DOESConsulting can help.
How It Works
MRTG is a powerful tool that allow you to graph just about everything we want. In this context, the context of load balancers, we can graph two basic types of data: Counters and gauges.
A counter is an OID variable that grows over time (for an explanation on OIDs, check the concepts page). For example, for a counter OID that tracks TCP connections, the number in the counter will increment by 1 every time a new connection is established. This number never gets smaller, it is always incrementing. MRTG polls a configured counter every 5 minutes, subtracts the last number it got, and devides it by the number of seconds in 5 minutes. This gives us a number, in instances per second, that this event (TCP connection being opened) has occured. Here is an example:
10:10am: 123394 connections 10:15am: 138854 connections 138854 - 123394 = 15460 connections in the past 5 minutes 15460 connections / 300 seconds (in 5 minutes) = 52 connections per second (rounded)
The number is rounded because MRTG only deals in positive integers.
A Gauge is a different type of variable. A gauge integer will go up an down according the variable it tracks. For instance, concurrent TCP sessions on a given device is considered a gauge. There is no math done on a guage OID, it just takes the number polled and graphs that number.
Counters and gauges are good for measure different types of metrics. Concurrent sessions, for instance, can only really be measured by a gauge. At a specific moment in time, we are measuring how many active TCP sessions there are. Bandwidth is best measured by a counter. Every time a bit passes an interface, the interface counter is incremented. We can then use the formula above to calculate the average number of bits/s that occured between those 5 minute intervals.
To put it simply, any item that we need in something per second, we need to have a counter. If we just need a varialbe graphed, then we need a gauge.
Some content courtesy of vegan.net
Note: BIG-IP®, 3DNS®, Globalsite® and F5 Networks® are registered trademarks of F5 Networks, Inc.
* DOESConsulting is not affiliated with F5 Networks®, nor has F5 Networks® endorsed DOESConsulting as a qualified consulting company.