"It is slow every Monday at nine"
Staff say the system crawls every Monday at nine. By the time a technician looks, it is fine again.
Without records, there is nothing to look at. A technician who monitors can see the Monday rush and say what caused it.
Key words
| Word | What it means |
|---|---|
| Monitoring | watching a system over time and recording how it behaves |
| Performance | how fast and how well a system does its work |
| Load | how busy a computer is |
| Traffic | the data moving along a link |
| Network | computers joined together so they can share data |
| Firewall | a barrier that blocks unwanted traffic |
| Baseline | the normal readings, to compare new ones against |
| Security control | a tool or rule that protects a system, such as a password rule |
| Bottleneck | a part that holds everything else back |
| Database | an organised store of records you can search |
The cells students fill in are left blank in this preview.
By the end of this lesson
Note
I can say what to monitor in hardware, software, database, network and people, and read some basic readings.
Starter
Have a go
Starter
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.
Five things to analyse
A system is more than its computers. A technician looks at five parts.
Hardware: is the processor, memory or disk full or too hot? Software: do programs crash or show errors? Database: are searches slow, or is it nearly full? Network: is the link slow or dropping data? People: are users stuck, untrained or making the same mistake?
What to watch in each part
| Part | Signs of trouble | Example reading |
|---|---|---|
| Hardware | High load, full disk, high heat | Load above the number of cores |
| Software | Crashes, error messages, slow start | Same error logged all day |
| Database | Slow searches, almost full | A report takes minutes |
| Network | Slow, dropped data, a very busy link | A link at its limit |
| People | Many tickets on one thing; repeat mistakes | Ten tickets about one program |
The cells students fill in are left blank in this preview.
How busy is the machine?
uptimeA command for the lesson’s lab terminal. It is shown here and not run.
How much memory is used?
free -m | head -2A command for the lesson’s lab terminal. It is shown here and not run.
How full is the disk?
df -h / | tail -1A command for the lesson’s lab terminal. It is shown here and not run.