مانیتور کردن سرور

Monitoring is a very important part of the web hosting business. We are not talking about monitoring log files or so. What we are talking about is monitoring services and uptime and what to do with the information.
Monitoring uptime. For a web hosting business server uptime is a very critical issue. If your servers keep on going down all day long your customers will be very upset. They pay you for web hosting and expect something in return. Uptime is one thing they expect from you as the web host. Your clients only earn money from their websites when the websites are available on the Internet. If they don't earn money, you won't money very soon.
The first step when monitoring your server would be to monitor important services for functionality. HTTP, FTP, SMTP, POP3 and others are very critical and you should get notified as soon as they go down. There are two ways of getting this accomplished. You can run a monitoring script on the server itself or you monitor those services externally. Probably the best way would be a combination of monitoring.
Monitoring is good. But how much does it cost?
There are plenty of options available for you. "Free" is one of them. You got the server anyway - so why not use it. If you have only one server you can still monitor things and in many cases this is sufficient. A very good tool (available free of charge) is SIM (System Integrity Monitor). It is available for download here:
http://www.r-fx.org/sim.php
SIM is kind of easy to install. For now - please follow the easy to use instructions that come with the software. We are currently working on a detailed tutorial for SIM so that it can be added to our "Server Configuration" section soon.
SIM will run locally on your server and monitor what you tell it to monitor. It can also take certain action based on criteria selected by you. As an example - it can restart failed services automatically. Here is a list of the main features:
Features:
- Service monitoring of HTTP, FTP, DNS, SSH, MYSQL & more
- Event tracking and alert system
- Auto restart ability for downed services
- Checks against network sockets & process list to ensure services are online
- Advanced HTTP service monitoring, to prevent commonly encountered issues
- System load monitor with customizable warnings & actions
- Ability to auto restart system with definable critical load level
- Priority change configurable for services, at warning or critical load level
- Informative command line status display
- Easily customizable configuration file
- Auto configuration script
- Auto cronjob setup feature
- Simple & Informative installation script
- Integrated auto-update feature
But what do you do if your server crashes and SIM cannot send you a notification. How do you get notified then? You can sign up for 3rd services, which in return will monitor your system(s) - often from several locations worldwide. These services will email you in the event the fail-criteria are detected. Monitoring can be a plain ICMP ping, HTTP, SMTP, FTP, POP3, and others, or it can even be script based and verify content, login functionality, and database integrity. But this comes at a price. 3rd party monitoring is not always cheap and especially the new web host who has to be careful spending money too easily. One of the most reliable providers seems to be a company called Alertra. Alertra Website Monitoring Service - their current pricing scheme looks like this:

Availability Services
60 min
30 min
20 min
10 min
5 min
2 min
1 min
Most Popular Services...
PING
0.95
1.95
2.95
5.95
11.95
29.95
59.95
HTTP-B
0.95
1.95
2.95
5.95
11.95
29.95
59.95
HTTP/S
2.95
5.95
8.95
17.10
32.40
76.50
144.00
HOST
9.95
14.95
19.95
24.95
29.95
49.95
69.95
Special Purpose Services...
TCP
0.95
1.95
2.95
5.95
11.95
29.95
59.95
SMTP
2.95
5.95
7.95
9.95
11.95
29.95
59.95
POP3
2.95
5.95
7.95
9.95
11.95
29.95
59.95
IMAP4
2.95
5.95
7.95
9.95
11.95
29.95
59.95
TELNET
2.95
5.95
7.95
9.95
11.95
29.95
59.95
SSH
2.95
5.95
7.95
9.95
11.95
29.95
59.95
DNS
2.95
5.95
7.95
9.95
11.95
29.95
59.95
NNTP
2.95
5.95
7.95
9.95
11.95
29.95
59.95
FTP
2.95
5.95
8.95
17.10
32.40
76.50
144.00
Custom Script
14.95
29.95
39.95
49.95
79.95
149.95
249.95

Source: Alertra.com / December 2005
There are several other companies available - offering similar services. We have not used any specific company but our former web host had the Alertra Monitoring Service purchased for his business and even offered the statistics to us (the clients). No problems here.

If you do not require monitoring from several locations worldwide but still would like to monitor your system(s) and services you can even do it right from your workstation in home office (assuming that the computer would be running 24/7 and be connected to the Internet via Broadband). The following product is called "IPCheck" and we have used it for several years - even monitoring a web-based product for Wall Street in a data center environment. The software installs on any Windows operating system and is very easy to configure. The software allows several ways to notify you - including even sending a page through your dial-up modem to your cell phone or pager. IPCheck is available here: IPCheck Server Monitor - uptime monitoring tool | continuous and remote network monitoring. - The makers of IPCheck now even offer a web-based monitoring service, too.
http://www.ipcheck-server-monitor.com/home (free trial)
Here are more monitoring services:
http://www.hyperspin.com
http://www.siteuptime.com
http://www.websitepulse.com
Monitoring can also be used as a very good marketing tool. Showing uptime statistics in public can create trust in your services and therefore motivate customers to sign up with you (if the uptime for your servers is note-worthy). Many of the products and services mentioned here will allow you to publish the statistics on your home page. If your server uptime is note-worthy - use it as a marketing tool. Hard numbers can be making the difference ....