Archive

Articles taggués ‘monitoring’

Configuration d’un serveur dédié de A à Z

17/03/2024 Aucun commentaire

Installation, configuration et administration d’un serveur dédié

debianCes tutoriaux ont été réalisés sous Debian (versions Etch 4.0 et Lenny 5.0) mais peuvent être transposés à d’autres distributions Linux, notamment Ubuntu. Ils sont applicables aux serveurs dédiés 1&1, Dedibox, OVH, Amen, et bien d’autres.

warning Tous les tutoriaux sont basés sur un serveur nommé test.alsacreations.com pour lequel nous disposons d’un utilisateur dew et d’un accès root (super-administrateur), chacun avec leur propre mot de passe.

Nous partons de l’idée d’obtenir un serveur web avec tout ce qu’il faut pour héberger plusieurs domaines et sites. Vous pouvez tout configurer à la main ou bien faire confiance à un panel d’administration.

Liste complète sans panel web

idee Ces tutoriaux conviennent à l’installation complète d’un serveur

  1. Première connexion : SSH, accès root et bases
  2. Apache et PHP : le serveur web
  3. MySQL : les bases de données
  4. Proftpd : le serveur FTP
  5. Postfix : le serveur mail POP3 et SMTP
  6. Sauvegarde automatique : avec backup-manager et export FTP
  7. Sécurisation : les règles de base, un firewall avec iptables, fail2ban…
  8. Bind : exécuter le serveur DNS en chroot
  9. Monitoring : garder un oeil sur son serveur grâce à monit et logwatch
  10. Roundcube : un webmail léger et rapide

Liste complète avec panel d’administration DTC

dtclogo

idee Si vous choisissez d’installer le panel d’administration DTC, suivez ces tutoriels. DTC se chargera de la configuration du reste des services.

  1. Première connexion : SSH, accès root et bases
  2. Bind : exécuter le serveur DNS en chroot
  3. Sécurisation : les règles de base, un firewall avec iptables, fail2ban…
  4. Panel DTC : pour installer et gérer les services web, ftp, mysql, e-mail, dns…
  5. Monitoring : garder un oeil sur son serveur grâce à monit et logwatch
  6. Sauvegarde automatique : backup-manager et export FTP
  7. Roundcube : un webmail léger et rapide

Attention : nous préconisons désormais l’utilisation du panel ISPConfig, en lieu et place du panel DTC. Il est tout aussi simple à installer et à utiliser. Veuillez vous référer à sa documentation.

20 Linux System Monitoring Tools Every SysAdmin Should Know

21/02/2024 Comments off

monitoring toolsNeed to monitor Linux server performance? Try these built-in command and a few add-on tools. Most Linux distributions are equipped with tons of monitoring. These tools provide metrics which can be used to get information about system activities. You can use these tools to find the possible causes of a performance problem. The commands discussed below are some of the most basic commands when it comes to system analysis and debugging server issues such as:

  1. Finding out bottlenecks.
  2. Disk (storage) bottlenecks.
  3. CPU and memory bottlenecks.
  4. Network bottlenecks.

#1: top – Process Activity Command

The top program provides a dynamic real-time view of a running system i.e. actual process activity. By default, it displays the most CPU-intensive tasks running on the server and updates the list every five seconds.

top-output-269x300Commonly Used Hot Keys

The top command provides several useful hot keys:

Hot KeyUsage
tDisplays summary information off and on.
mDisplays memory information off and on.
ASorts the display by top consumers of various system resources. Useful for quick identification of performance-hungry tasks on a system.
fEnters an interactive configuration screen for top. Helpful for setting up top for a specific task.
oEnables you to interactively select the ordering within top.
rIssues renice command.
kIssues kill command.
zTurn on or off color/mono

Lire la suite…

MySQL – Monitorer le port 3306

04/02/2024 Comments off

Pour faire le monitoring du port 3306 sous Linux il suffit d’utiliser la commande :

tcpdump  -i eth0 -nN -vvv -xX  -s 1500  port 3306

s représente la longueur du paquet.

Find all active IP addresses in a network

17/01/2024 Comments off

Today I found myself reconfiguring a wireless access point I hadn’t used in a very long time. I no longer have the manual (so I could reset it to factory defaults) nor do I remember what the obscure IP address I configured it with was. Luckily I do know what network it’s setup for ( 192.168.1.x ) but I don’t want to have to try to connect to all 254 IP addresses (192.168.1.1 through 192.168.1.254) as that would take quite some time.

So what I’m going to do is use Nmap a swiss army knife for network operators and system admins. What we’re going to do is use Nmap to scan the entire network and tell us which IP addresses are active. This will allow us to drastically reduce the number of IP addresses we have to try.

There are Nmap versions for all three major OS’s *nix, OS X and Windows. I’ll be showing you the syntax for the *nix/OS X version.

nmap -sP 192.168.1.0/24

replace 192.168.1.0/24 with whatever network it is you’re trying to scan.
The /24 is the netmask of the network in CDIR notation. If you need a cheat sheet you can find one here

Once you press return (or enter) Nmap will start to work pinging each and every IP address on your network and noting which ones respond and which don’t. (Note that if your device has a firewall that discards ping requests it will appear to be down to this scan)

You’ll quickly get an output similar to the following

Starting Nmap 4.50 ( http://insecure.org ) at 2008-08-19 10:15 PDT
HOST 192.168.1.25 appears to be up.
MAC Address: 0:0F:1F:4C:0B:E6 (WW Pcba Test)
Nmap finished: 256 IP addresses (3 hosts up) scanned in 5.711 seconds

Monitor Network Connections in Mac OS X for Free with Private Eye

11/01/2024 Comments off

Source: OSXdaily

Private Eye is a free real-time network monitor app for Mac OS X that is extremely easy to use. Upon launching the app, you’ll start to see all open network connections by application and process, and you can then filter connections by app, monitor all open connections, or watch only incoming or outgoing transfer.

private-eye-network-connection-monitor-mac

Connections are reported by application, the time of the connection, and arguably the most useful, the IP address that is being connected to by the app, making it easy to see socket and routing data, letting you know exactly what app is communicating with what server or IP address, for both local and broader internet networks. If you have any interest in networking, privacy, security, or you just want to keep an eye on what apps are connecting to the internet and to where, you should download this app, but it’s also an amazingly useful tool for troubleshooting network problems and figuring out what is using the network.

 

Download and install Private Eye by putting it into your /Applications/ folder, then open PrivateEye to get started. The list of open network connections is easy to read, you’ll see a time stamp of the connection, the application name, and where the connection is going to by IP (or coming from, as determined by the arrow pointing left for in, or right for out).

private-eye-connections

Using the left side menu you can quickly break down connections to see them all, only show incoming transfers, outgoing connections, or display connections by specific application only. Apps are easy to identify in this list, as are daemons running in the background (like PubSubAgent), and command line processes belonging to the user are also visible (ssh, for example).

This is a simple yet powerful tool without the complexity or the learning curves related to compiling and using the command line tools lsof, watch, open_ports, or wireshark, and is therefore highly recommended for anyone who is interested in seeing this kind of information, whether it’s out of general curiosity, or to help troubleshoot and diagnose specific network activities.