Shulou(Shulou.com)06/01 Report--

This article shows you how to solve Service Unavailable, the content is concise and easy to understand, can definitely brighten your eyes, through the detailed introduction of this article, I hope you can get something.

First, if there is a "Service Unavailable" prompt, refresh a few times and then access it.

This occurs because your website exceeds the iis limit.

Because the operating system of 2003 does not prompt too much IIS like the 2000 system prompts "too many links", but prompts "ServiceUnavailable", this situation is caused by the website exceeding the system resource limit, mainly because the program takes up too many resources.

For example, the same 100-person online forum, Lei ao Forum accounts for more than 10 times the resources of the PW Forum; in addition, some endless-loop programs, or unoptimized programs will take up too many system resources, and the system resources are obviously limited. However, in WINDOWS2003's operating system, websites run as independent processes and do not affect each other.

If the program of a website takes up too many resources or there are too many errors, the system log will prompt: "Application pool 'xxx' is automatically disabled because of a series of errors in the process of servicing this application pool, or prompt: application pool' xxx' exceeds its job limit setting. At this point, visiting the site will prompt: ServiceUnavailable. Generally, the system will return to normal in about 30 seconds, and the system can be accessed normally after a few more refreshes.

In addition, if your website currently has too many visitors and exceeds the system's iis connection limit, there will also be a ServiceUnavailable prompt (if there are too many connections under the win2k host, it will prompt: too many connections, please try again later, while the host of win2003 has just directly prompted: ServiceUnavailable)

Second, there is no restriction on IIS connection, or encounter Service Unavailable

It is more common on websites that use ACCESS databases.

Generally speaking, users who use windows2003IIS6 may have this problem all the time. Suddenly, a website cannot be opened.

Tip: ServiceUnavailable, but this site does not limit the number of IIS connections. Then it immediately affected other websites, and after a while, all other websites became ServiceUnavailable.

What is the reason for this? / / this article is from www.yisu.com

After analysis, we can see that it is still an old problem of MS. The ACCESS engine is down. Fix it with the server doctor's file, and when you look at the repair results, you will find that some files cause a "catastrophic failure" of the ACCESS engine and errors that "the object reference is not set to the object's instance". The system will not return to normal until it is repaired by the file doctor.

Third, when browsing a WindowsSharePointServicesWeb site, prompt: ServiceUnavailable

This problem can occur when the application pool for virtual servers is not configured correctly in 1.MicrosoftInternet Information Services (IIS) 6.0.

Solution

To solve this problem, follow these steps: 1. Verify that the application pool is configured for the virtual server. The default application pool is MSSharePointPortalAppPool.

Follow these steps to determine which application pool the virtual server is using.

a. Click start, point to Administrative tools, and then click Internet Information Services (IIS) Manager.

b. Expand ServerName, expand Web sites, right-click the virtual server, and then click Properties.

c. Click the Home Directory tab. The application pool configured for the virtual server is listed in the Application Pool box.

d. Click OK.

two。 Verify that the password used by the application pool account is correct. IIS does not automatically poll the ActiveDirectory directory service for password changes. If the application pool account is a domain account whose password has expired, you may receive the error message described in the symptoms section of this article after you reassign a new password for this account.

3. Verify that the application pool account is a member of the IIS_WPG group and the STS_WPG group on the server.

4. Restart IIS to recycle the application pool

The reason for the emergence of ServiceUnavailable

The emergence of ServiceUnavailable is generally due to lack of resources, such as IIS, CPU, memory and so on.

All of our virtual hosts do not restrict IIS, so we can rule out insufficient IIS.

All our server operating systems are windows2003, and one of the key things is "application pool".

In general, 30-50 stations share a program pool, this program pool can be simply understood as a resource library, that is, these 30-50 stations share this resource. We limit the CPU footprint of a program pool to 60% and the memory usage to 200m.

If this resource is used up by one of the stations, the program pool will stop, and all stations that use the program pool will be prompted to run out of "ServiceUnavailable" resources until the program pool is restarted.

In most cases, 60% of CPU and 200 megabytes of memory are perfectly adequate; if there are spam programs or attacks, there can be a sharp rise in CPU or heavy memory usage, which is the reason for most "ServiceUnavailable". Judging from the situation we have monitored so far, most of the CPU occupies between 90% and 100%.

1. What if "ServiceUnavailable" appears?

We have developed a special program to monitor and repair IIS, automatically check IIS every 10 minutes, and restart if we find that the program pool stops. Therefore, once there is a "ServiceUnavailable", no more than 10 minutes, it will be automatically repaired, in most cases only 2-5 minutes. Most other companies do not have monitoring programs, so they can only be repaired manually, usually for a duration of 2-6 hours to find and start.

2. What if "ServiceUnavailable" occurs frequently?

If this prompt occurs frequently, it indicates that there is something wrong with one of the stations that share resources with you. Please contact our technician for troubleshooting.

3. Is the occurrence of "ServiceUnavailable" a server problem?

Many people think that it is the problem of server instability, but it is not. If it is a server problem, there will not be a "ServiceUnavailable" prompt, but directly paralyzed, even FTP can not go up.

This occurs because some stations consume a lot of resources, and the resources of the server are always limited. If the server exceeds the set value for a long time, the server will automatically stop this program pool to prevent users of other program pools from being affected.

The above content is how to solve Service Unavailable. Have you learned any knowledge or skills? If you want to learn more skills or enrich your knowledge reserve, you are welcome to follow the industry information channel.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.