What is IT Monitoring

Transcription

1 What is IT Monitoring And Why Should You Use It? Opsview Technical Overview

2 Page 2 What is IT Monitoring and Why Should You Use it? Contents What is IT Monitoring...3 Monitoring Philosophy: A Hierarchical Approach...3 The Foundation Layer...3 The Monitoring Layer...4 The Interpretation Layer...6 Closing Thoughts...10 Case Study...11

3 Page 3 In Opsview, like in many other IT monitoring/ Application Performance Management companies, we like to talk about the next generation of monitoring and the new features that are constantly being released and developed; from multi-tenancy and scalability through to service monitoring, dashboards, cloud, etc. However, there is a lot of assumed knowledge that goes views into the operational status of those devices, i.e. I know that my server is up and running, I also want to make sure that the hard drive doesn t run out of space. This is called a service check; checking that hard drive is working, that the CPU isnt 100% busy, etc. This leads us onto the hierarchical approach to monitoring. Monitoring Philosophy: A Hierarchical Approach before each of the aforementioned items the basics of what IT monitoring is and what the information provided by IT monitoring means to an organization. Monitoring has an intrinsic hierarchy in such that certain objects must exist in a certain order. What is Monitoring? In order to monitor our server s C:/ drive, we must first monitor our server. This is obvious. However sometimes The essence of IT monitoring is simple ensuring that your IT equipment is available and performing to the level expected and required to maintain business as normal. the syntax and naming is very confusing, given that it often differs from vendor to vendor with some calling the server a host or a monitor, and some calling the C:/ drive style checks monitors, service checks, counters, etc. In the following paragraph, hopefully In basic monitoring solutions this is often done by simply sending a ping to the device and awaiting a response. If a response is obtained, then the user can be assured that the server/router/switch is up and hasn t this syntax should become clearer as we step through each of the 3 layers. The Foundation Layer been powered off, crashed etc. This function allows a system administrator a simple view into their IT estate, and to ensure that IT systems are available. The first of our 3 layers is the foundation layer. This layer of monitoring forms the basis of the advanced monitoring discussed later. Here we monitor our More advanced monitoring solutions allow detailed physical or virtual devices, called hosts such as a

4 Page 2 Windows server, Linux server, Cisco router, Nokia firewall, VMware virtual machine, etc and these are often the lowest level of the stack and we ensure they are up by pinging them. Once configured, this allows us a view such as the image shown (right) into the devices we have added and which ones are up or down allowing us to see if a device has crashed or been powered off. devices on a host The Monitoring Layer Once we know the physical/virtual hardware is up, we want to monitor items running on them. These could be: a. Linux servers: Swap space, CPU Usage, FS usage, Service running, etc. b. Windows servers: Pagefile size, memory usage, CPU Usage, C:/ space, processes, etc. c. Network devices: throughput on interfaces, CPU load, memory, etc. d. VMware/Virtualization: Datastore free, temperature checks, number of VM s, CPU, etc. We refer to these items as service checks and they run against the hosts that we configured and specified in the foundation layer. A common scenario is: I ve added my Windows Server, windows001.domain.com, as a host and I can see that it is up (step 1). Now I want to monitor some items on it, so I ll add a C:/ Drive check, a CPU Check, and a Memory Check, along with a few others. Now I can not only see that my host is up, but I m also monitoring performance items on that server, giving me a better view into its operational performance.

5 Page 3 host templates This gives a good insight into server health and performance. However, the issue we have now is that to add 100 hosts (e.g. Windows servers) and then 6 service checks to each of those hosts, could take a long time. So in Opsview and a few other monitoring solutions, we have the concept of grouping these service checks together into a Host template. We give a group a meaningful name i.e. Windows Servers, to which we can add lots of service checks. This template can then be applied en-masse to all the Windows servers, reducing the time it takes to implement all our checks. service checks

6 Page 4 Now we have templates to speed up our configuration time, our only time consuming task is adding these hosts hostname by hostname. Again, innovation in monitoring has deemed this an unnecessary evil with the creation of autodiscovery. Autodiscovery allows a monitoring system to search and scan a predefined subnet or network and find devices on that network. In our Windows example, we can scan the subnet and discover all hosts on that network and import them into our monitoring system, ready to be modified and have host templates added to. autodiscovery scans in Opsview In Opsview, we can even determine the Operating System and apply templates automatically based on the results, meaning the time-to-value is extremely low.

7 The Interpretation Layer Page 5 Now that we are monitoring our hosts and also the services running on them, we can start to be intelligent with the interpretation of the data. i.e. how do we present this so that we can clearly see that a problem is occurring? Commonly in IT, servers and network devices make up larger objects such as applications, websites, services, etc and these are the items we actually want to monitor, rather than the actual items which they consist of. Ultimatley the failure of an IT system is what will impact our business and our customers, so prevention of these problems is the goal for the monitoring. Example: I run an e-commerce website and I want to know when this website is impacted by IT issues and what part of this website is impacted. We know that this website is made up of a few Apache servers, running on 2 Linux servers, connected to the internet via a router and a switch, and also relying on a DNS server. In the monitoring layer outlined in the previous section, we are using service checks to monitor performance metrics for each of these areas individually, i.e: Apache: number of requests per second, number of apache processes, etc. Linux servers: CPU usage, memory usage, hard disk drive space, temperature, etc. Switch/Router: CPU load, RAM usage, interface throughput, packets per second, etc. DNS Server: DNS service running, performance counters, queues, etc. website service checks

8 Page 6 This gives us a great view into how each of these components is doing. What we want now is to look at it holistically; for example as a website rather than a series of objects. To do this, Monitoring software vendors / APM vendors have created business process monitoring. Business process monitoring allows users a view into the performance of their applications, stacks, websites etc, rather than having to look at all the individual components and work it out for themselves. This is what takes an average monitoring tool to the next level how it deals with services and top down views, compared to bottom-up views i.e. focusing on business services rather than components within the service. In Opsview, we have the concept of Keywords. These allow users to take individual service checks from individual hosts and group them together logically in a way that is easy to understand, for example My Website. From here we can create a traffic light view into our services as demonstrated in the following example. traffic light view of business services Once we have configured our keywords, not only can we monitor based upon them i.e. using the above view to see the actual health of my Service or accounting application, but I can use this keyword in my events console to show only events relating to my service related hardware:

9 Page 7 keyword event console This allows me to see all the events that have happened on any piece of hardware (server through to the switches), that have an effect on the performance of my website, service, customer, etc. In Opsview these keywords can then also be used in our reports module, to show the historical health of the various monitored services in a number of formats; business reports such as SLA reports or cost of downtime reports, through to technical reports such as performance reports, availability reports, etc. reporting in Opsview

10 Page 8 These reports can also be automated and delivered regularly (daily, weekly, monthly etc) so that you can easily see the performance/availability/cost of downtime for any pre-defined keyword. Closing Thoughts Although the task of monitoring whether a device is up or down may seem relatively simple, the potential consqences of the outcome of this check can be huge for an organization reliant on IT systems. The intention of this article was to demonstrate how IT monitoring functions from a tiered approach, from simple monitoring of whether a device is responsive, through to using business process monitoring (BPM) to view the health of services, view cost of a service being down, and to see how business service availability may impact an orgainzation. Opsview Enterprise 4.3 monitoring dashboard

11 Page 9 Case Study - We7 We7 is a free, advertising-supported music service with over 15 million tracks available for streaming in the UK and Ireland. Former Genesis frontman, Peter Gabriel, and serial entrepreneur, Steve Purdham, started the firm in 2009 after securing content deals with Universal, Sony, Warner and EMI. Whilst in start-up mode We7 s IT resources and budget were limited. Fortunately their Head of Network Operations, Stuart Teasdale, preferred using open source IT monitoring software believing that, with the right knowledge, it can be used to replace most expensive proprietary datacenter services. Similarly he advocates the use of commodity hardware to do the heavy lifting. Tesco, one of the world s largest retailing brands, acquired We7 in June 2012 as part of its strategy to diversify into the entertainment market. After the acquisition, there was pressure on us to beef up our IT monitoring capabilities so that we could identify potential issues before they started impacting critical services to our customers, said Teasdale. In their evaluation of replacement monitoring tools the We7 team favored a solution that could leverage their extensive knowledge of open source software. We looked at a number of tools including Zabbix and Nagios but were disappointed by their distributed monitoring capabilities - they were just too clunky for our production environment, said Teasdale. For us, Opsview s slave server monitoring features are second to none which is why we made the decision to invest in Opsview Enterprise.