Weight: 2
Description: Candidates should be able to monitor resource usage to predict future resource needs.
Key Knowledge Areas:
- Use monitoring and measurement tools to monitor IT infrastructure usage.
- Predict capacity break point of a configuration
- Observe growth rate of capacity usage
- Graph the trend of capacity usage
- Awareness of monitoring solutions such as Icinga2, Nagios, collectd, MRTG and Cacti
The following is a partial list of the used files, terms and utilities:
- diagnose
- predict growth
- resource exhaustion
Predicting The future is one of the hardest work ever, can you remember "Dorithy and the witches of the OZ"? :) Many System Administrators wish if they had some thing like Glass Ball. They wish they could realize what kind of problems might happen next day, in order to avoid it today. But unfortunately that is impossible. So forget about that and lets talk about real environment. In computer science predicting future is possible just by archiving and processing what has happened in past.Mathematical science and statistics can analyze old data and graph trends to predict future.
there are some tools to help us:
- Icinga2
- Nagios
- collectd
- MRTG
- Cacti
We can spend a whole course for each of these tools, but for LPI exam we are wanted to know about their existence. So we just Introduce them and there is no need to memorize differences 1:
| Cacti | Collectd | Icinga | Nagios | |
|---|---|---|---|---|
| IP SLA Report | Yes | No | Via Plugin | Via Pugin |
| Logical Grouping | Yes | No | Yes | Yes |
| Trending | Yes | No | Yes | Yes |
| Trend Prediction | Yes | No | No | No |
| Auto Discovery | Yes | Push Model ,Multicast possible | Via Plugin | Via Plugin |
| Agentless | Yes | Supported | Supported | Supported |
| SNMP | Yes | Yes | Via Plugin | Via Plugin |
| Syslog | Yes | Yes | Via Plugin | Via PLugin |
| Plugins | Yes | Yes | Yes | Yes |
| Triggers / Alerts | Yes | Yes | Yes | Yes |
| WebApp | Full Controll | Viewing | Full Control | Yes |
| Distributed Monitoring | Yes | Yes | Yes | Yes |
| Inventory | Yes | No | Via Plugin | Via PLugin |
| Platform | PHP | C | C | C |
| Data Storage Method | RRD tool,MySQL | RRD tool | MySQL,PostgreSQL,Oracle Database | Flat File, SQL, MySQL |
| License | Commercial | GPL V2 | GPL | GPL |
| Maps | Yes | No | Via Plugin | Yes |
| Access Control | Yes | Apache acl | Yes | Yes |
MRTG (Multi Router Traffic Grapher ) is simple Tiny Tool which was written in Perl ,It works based on SNMP traffic which it received from Configured Devices and Nodes. Most of the time is used to monitor Bandwidth of Network Nodes. It shows basic HTML graph using GIF or PNG files.
Do not forget, Capacity Calculation, Predicting future needs and have a good sense of IT environment need years of experience.