issue149:certifie_linux
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Prochaine révision | Révision précédente | ||
issue149:certifie_linux [2019/10/01 09:02] – créée d52fr | issue149:certifie_linux [2019/10/10 16:03] (Version actuelle) – andre_domenech | ||
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- | Welcome back learners, and a nod to those “just interested”. We are continuing from last issue with the very first topic, capacity planning. We are still busy with resource availability and troubleshooting. Last issue, we covered netstat and how you can use it to troubleshoot. This time, let us look at predicting the future... <queue spooky music> | + | **Welcome back learners, and a nod to those “just interested”. We are continuing from last issue with the very first topic, capacity planning. We are still busy with resource availability and troubleshooting. Last issue, we covered netstat and how you can use it to troubleshoot. This time, let us look at predicting the future... <queue spooky music> |
- | This is the final part of measuring and troubleshooting before we move on to the exciting topic of the kernel. The nice thing about Linux is that you are spoilt for choice, even if you don’t know it. There are many – yes, many – monitoring tools for Linux and that list grows each day. The LPI want you to know of some of them. You have to understand that the LPIC is a grooming certification for enterprise – so we look at enterprise products here. Usually, those with colourful dashboards. Therefore, I will start you off with some homework – you need to Google Cacti, Nagios, MRTG, and read the ‘about’ sections on their respective home pages. If you feel brave, you can install them at home to play with. (If I remember correctly, I botched my first Cacti install, but you don’t break anything). | + | This is the final part of measuring and troubleshooting before we move on to the exciting topic of the kernel. The nice thing about Linux is that you are spoilt for choice, even if you don’t know it. There are many – yes, many – monitoring tools for Linux and that list grows each day. The LPI want you to know of some of them. You have to understand that the LPIC is a grooming certification for enterprise – so we look at enterprise products here. Usually, those with colourful dashboards. Therefore, I will start you off with some homework – you need to Google Cacti, Nagios, MRTG, and read the ‘about’ sections on their respective home pages. If you feel brave, you can install them at home to play with. (If I remember correctly, I botched my first Cacti install, but you don’t break anything).** |
- | For the LPIC level2, we need to know about ‘collectd’. Collectd is used to collect statistics of a particular system. What it collects is governed by its plugins. As the name suggests, it is a collector. (I think the ‘d’ at the end of the name gives it away – it’s a daemon). It does not automatically display colourful graphs and charts like Cacti or Nagios. If you want to play with it, I suggest setting up an Ubuntu LAMP server. Installing collectd is as easy as: | + | Chers apprenants, je salue votre retour, et je fais un coucou à ceux qui sont « juste intéressés ». Nous continuons la série suite au dernier numéro avec le tout premier sujet, la disponibilité des ressources. Nous nous occupons toujours de la gestion des ressources et le dépannage quand il y a un problème. Dans le dernier numéro, nous avons parlé de netstat et de la façon dont vous pouvez l' |
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+ | Cette fois-ci, il s'agit de la dernière partie du chapitre sur les mesures et le dépannage avant d' | ||
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+ | **For the LPIC level2, we need to know about ‘collectd’. Collectd is used to collect statistics of a particular system. What it collects is governed by its plugins. As the name suggests, it is a collector. (I think the ‘d’ at the end of the name gives it away – it’s a daemon). It does not automatically display colourful graphs and charts like Cacti or Nagios. If you want to play with it, I suggest setting up an Ubuntu LAMP server. Installing collectd is as easy as: | ||
sudo apt install collectd | sudo apt install collectd | ||
Ligne 9: | Ligne 13: | ||
Once installed, head on over to: / | Once installed, head on over to: / | ||
- | sudo nano collectd.conf - please peruse the file. | + | sudo nano collectd.conf - please peruse the file. ** |
- | If you find the ‘plugins’ section, you will see some lines uncommented and this is where you decide what you want. Just be aware that some of the plugins require additional setup. If you look further down this file, you will find the “Plugin configuration” section. There you will see templates for things like Apache, and what the plugin needs to work. In Apache’s case, a template with user / password and certificate is provided. Do not comment out the ‘rrd-tool’ as your reports are in “.rrd” format. If you look at the rrdtool configuration, | + | Pour le niveau 2 de la LPIC, nous devons connaître « collectd ». Collectd est utilisé pour recueillir des statistiques d'un système en particulier. Ses greffons gouvernent ce qu'il recueille. Comme son nom l' |
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+ | sudo apt install collectd | ||
+ | |||
+ | Une fois l' | ||
+ | |||
+ | sudo nano collectd.conf | ||
+ | |||
+ | **If you find the ‘plugins’ section, you will see some lines uncommented and this is where you decide what you want. Just be aware that some of the plugins require additional setup. If you look further down this file, you will find the “Plugin configuration” section. There you will see templates for things like Apache, and what the plugin needs to work. In Apache’s case, a template with user / password and certificate is provided. Do not comment out the ‘rrd-tool’ as your reports are in “.rrd” format. If you look at the rrdtool configuration, | ||
service collectd stop | service collectd stop | ||
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but you know how to do this, right? As always, with services, double-check with: | but you know how to do this, right? As always, with services, double-check with: | ||
- | service collectd status - it is a good habit. | + | service collectd status - it is a good habit.** |
- | So where can we see these plugin’s are working? Head over to / | + | Si vous trouvez la section des « plugins » (greffons ou extensions), |
- | Let us have a look at this – head over to /var/lib/collectd/rrd – the default path in the collectd.conf-file (you can change this). Each server you tagged will have its own folder here in the FQDN format, so there is no confusion. If you go into one of the listed folders, you will see sub-folders which match your uncommented plugins in the collectd.conf file. Nice! See I told you Linux was easy! If you do not see how this ties up, please install collectd on an Ubuntu server and follow along. I have warned you about space, but I also need to warn you about running your disk ragged. Collectd constantly collects data, but only writes that data once every ten minutes. You can change this, but you do not want to write to the disk all the time. | + | service |
- | Gathering all this data is good and well, but how do you read .rrd-files or get an overview of what you have collected? | + | mais vous savez déjà comment faire cela, non ? Comme toujours, avec les services, revérifiez avec : |
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+ | service collectd status, c'est une bonne pratique. | ||
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+ | **So where can we see these plugin’s are working? Head over to / | ||
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+ | Let us have a look at this – head over to / | ||
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+ | Bon, où peut-on voir que ces greffons fonctionnent ? Allez à / | ||
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+ | Regardons cela : allez à / | ||
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+ | **Gathering all this data is good and well, but how do you read .rrd-files or get an overview of what you have collected? | ||
Obviously our lab LAMP server at home does very little, so you can use “stress” to stress the server a bit to get a bit of a spike in the data. The study guide walks you through getting the graphing up via a git repository (nethuis.nl), | Obviously our lab LAMP server at home does very little, so you can use “stress” to stress the server a bit to get a bit of a spike in the data. The study guide walks you through getting the graphing up via a git repository (nethuis.nl), | ||
- | To understand the needs of your organisation, | + | To understand the needs of your organisation, |
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+ | Rassembler toutes ces données, c'est bien mais comment lire des fichiers .rrd ou avoir une vue d' | ||
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+ | Bien évidemment, | ||
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+ | Pour comprendre les besoins de votre organisation, | ||
- | Before you tell me about all the other wonderful tools out there, I know, but you need to know this for your LPIC2 exam. | + | **Before you tell me about all the other wonderful tools out there, I know, but you need to know this for your LPIC2 exam. |
Now for a quick exam-type question: | Now for a quick exam-type question: | ||
Ligne 38: | Ligne 68: | ||
C. Identifying processes killed during out-of-memory occurrences. | C. Identifying processes killed during out-of-memory occurrences. | ||
D. Diagnosing capacity problems. | D. Diagnosing capacity problems. | ||
- | E. Troubleshooting a software problem. | + | E. Troubleshooting a software problem.** |
- | Did you have any difficulty in finding the correct answers immediately? | + | Avant que vous ne me décriviez tous les autres merveilleux outils qui existent, je le sais, mais c'est celui-ci qu'il faut connaître pour l' |
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+ | Maintenant, voici une question rapide de type examen : | ||
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+ | Quand les données historiques de l' | ||
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+ | A. La prédiction du moment où les ressources devront être augmentées. | ||
+ | B. Le choix d'un vendeur d' | ||
+ | C. L' | ||
+ | D. Le diagnostic des problèmes de capacité. | ||
+ | E. La résolution d'un problème de logiciel. | ||
+ | |||
+ | **Did you have any difficulty in finding the correct answers immediately? | ||
What mechanism does collectd use to gather monitoring information on systems? | What mechanism does collectd use to gather monitoring information on systems? | ||
Ligne 48: | Ligne 90: | ||
D. It makes SNMP queries to the clients being monitored. | D. It makes SNMP queries to the clients being monitored. | ||
- | You KNOW this answer! | + | You KNOW this answer!** |
- | If you would like to jump ahead, or test your skills at an LPI exam, do a test paper here: https:// | + | Vous n'avez pas trouvé les réponses exactes tout de suite ? (C'est A, D, E). Alors, prière de relire le chapitre dans le guide d' |
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+ | Quel mécanisme collectd utilise-t-il pour recueillir des informations de surveillance des systèmes ? | ||
+ | A. Il se sert d'une bibliothèque de greffons. | ||
+ | B. Un serveur maître se connecte à un service collectd sur chaque machine pour recueillir des informations. | ||
+ | C. Il recueille ses propres données sur chaque serveur et les envoie à un serveur maître. | ||
+ | D. Il envoie des questions SNMP aux clients sous surveillance. | ||
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+ | Vous CONNAISSEZ | ||
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+ | **If you would like to jump ahead, or test your skills at an LPI exam, do a test paper here: https:// | ||
• The new exam number is 201-400, 117-201 was the old one. | • The new exam number is 201-400, 117-201 was the old one. | ||
• The site does require signing up, but sign up with temporary email – not your real email. | • The site does require signing up, but sign up with temporary email – not your real email. | ||
• DO NOT learn these questions parrot fashion, as they are probably not real exam questions. | • DO NOT learn these questions parrot fashion, as they are probably not real exam questions. | ||
- | Let us know how you did – good or bad, it does not matter. Good, means you are ready to write and confident in your skills. Bad means you will be learning new stuff!! Yay! There is no downside here. If you do not know why an answer is the way it is, contact us. | + | Let us know how you did – good or bad, it does not matter. Good, means you are ready to write and confident in your skills. Bad means you will be learning new stuff!! Yay! There is no downside here. If you do not know why an answer is the way it is, contact us.** |
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+ | Si vous êtes impatient, ou voulez tester vos compétences face à un examen LPI, passez un test ici : https:// | ||
+ | • La nouvelle référence de l’examen est 201-400, l’ancienne était 117-201. | ||
+ | • Le site nécessite une inscription, | ||
+ | • N' | ||
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+ | Dites-nous comment vous vous en êtes sorti, bien ou mal, peu importe. Bon signifie que vous êtes prêts pour l’examen et que vous avez confiance en vos compétences. Mauvais veut dire que vous devez encore apprendre de nouvelles choses !! Chouette ! Et ce n’est pas un problème. Si vous ne comprenez pas le sens d’une réponse alors, contactez-nous. | ||
issue149/certifie_linux.1569913360.txt.gz · Dernière modification : 2019/10/01 09:02 de d52fr