Is there any way to know programmatically when Apache Web Server and/or deployed application started/restarted?
You can fetch the mod_status page for Apache (usually at /server-status - see https://httpd.apache.org/docs/2.4/mod/mod_status.html).
Then you can parse the output to see what "Restart Time" says.
It depends on what OS we're talking about here.
Assuming its Linux/Unix, the start time of a process can be output by the ps command but note that this will (depending on the MPM) return multiple records of different ages for httpd - the base process will be the oldest / the parent of the other processes.
On Linux, this information is also exposed in the proc filesystem - but note that a lot of the files describing the process are changed during its lifetime - but the directory (/proc/$PID) and exe (/proc/$PID/exe) don't.
Related
I inherited a server on which a large number of applications and files are installed.
Many of these are no longer in use, but I have no documentation of what is in production and what is not.
I should try to clean up and remove unused files and applications.
Since I have Apache logs, can I process them with an analyzer or some script to identify the files (or rather the folders) that are no longer in use (which have not had hits since January 2020 for example)?
Any help is appreciated.
In the end I solved it by simply using the grep command.
I used the Apache logs from January to now, and for each folder on the server I launched a command like:
cat access_log_20200* |grep "GET /folder"
So I deleted the ones that are not present in the log file.
I am doing some reverse engineering on a website.
We are using LAMP stack under CENTOS 5, without any commercial/open source framework (symfony, laravel, etc). Just plain PHP with an in-house framework.
I wonder if there is any way to know which files in the server have been used to produce a request.
For example, let's say I am requesting http://myserver.com/index.php.
Let's assume that 'index.php' calls other PHP scripts (e.g. to connect to the database and retrieve some info), it also includes a couple of other html files, etc
How can I get the list of those accessed files?
I already tried to enable the server-status directive in apache, and although it is working I can't get what I want (I also passed the 'refresh' parameter)
I also used lsof -c httpd, as suggested in other forums, but it is producing a very big output and I can't find what I'm looking for.
I also read the apache logs, but I am only getting the requests that the server handled.
Some other users suggested to add the PHP directives like 'self', but that means I need to know which files I need to modify to include that directive beforehand (which I don't) and which is precisely what I am trying to find out.
Is that actually possible to trace the internal activity of the server and get those file names and locations?
Regards.
Not that I tried this, but it looks like mod_log_config is the answer to my own question
Am trying to access my website by its IP address. The site is hosted on a shared ip so, i tried including a tilde ~ and then my user name, but it doesn't seem to work.
Any idea around this?
http://serverIPaddress/~cpanelusername
Most likely this is happening because of mod_ruid2 being installed. In order to access the site via publicIPaddress/~username you have to install mod_userdir.
unfortunately you can't use mod_userdir and mod_ruid2 at the same time. So these are the steps for configuring your WHM to allow access with ip/~username
Login to WHM with your root user. Go to mod_userdir TWEAK which you can access using the search bar on the left side of the GUI.
At this point check the box to install the service. After it installs you should be able to access the site with ip/~username. It is very likely it will not install because there are conflicts with mod_ruid2 and CGI being installed. So you remove them like this,
Go back to the search bar and type EasyApache. Click the link when it pops up,
Click customize and then next or click Server Modules on the left. In the main area and your current setup will load. First type mod_ruid2 in the search bar. When it pops up click to uninstall it.
Next search for CGI and if ea-apache24-mod_cgi uninstall it as well.
Now you need to use another handler so in my case I chose suphp.
ea-apache24-mod_suphp
Once you choose to install it you will need to choose Prefork Worker or Event.
Here are the descriptions of these,
Prefork With the Prefork module installed, Apache is a non-threaded,
pre-forking web server. That means that each Apache child process
contains a single thread and handles one request at a time. Because of
that, it consumes more resources than the threaded MPMs: Worker and
Event.
Prefork is the default MPM, so if no MPM is selected in EasyApache,
Prefork will be selected. It still is the best choice if Apache has to
use non-thread safe libraries such as mod_php (DSO), and is ideal if
isolation of processes is important.
Worker The Worker MPM turns Apache into a multi-process,
multi-threaded web server. Unlike Prefork, each child process under
Worker can have multiple threads. As such, Worker can handle more
requests with fewer resources than Prefork. Worker generally is
recommended for high-traffic servers running Apache versions prior to
2.4. However, Worker is incompatible with non-thread safe libraries. If you need to run something that isn’t thread safe, you will need to
stick with Prefork.
Event Each process under Event also can contain multiple threads but,
unlike Worker, each is capable of more than one task. Apache has the
lowest resource requirements when used with the Event MPM.
Event, though, is supported only on servers running Apache 2.4. Under
Apache 2.2, Event is considered experimental and is incompatible with
some modules on older versions of Apache. Nevertheless, on
high-traffic Apache 2.2 servers where Apache has experienced issues
with memory, upgrading Apache to take advantage of the Event MPM can
yield significant results.
After you are done installing the new modules and removing the old ones you need to ssh into your server and type
For Centos 7
/usr/local/cpanel/bin/rebuild_phpconf --available
This will show you something like this,
At this point I checked my current php install like this,
php -v
PHP 5.6.27
So I decided to go with the correlating PHP version for my handler. So now you have to select the handler like this,
/usr/local/cpanel/bin/rebuild_phpconf --default=ea-php56 --ea-php56=suphp
At this point make sure you go back to mod_userdir in your whm search bar and try and install it again. If it installs with no errors then try and access the page in your browser with ipaddress/~username. If you still can not access it then go back to your mod_userdir screen and make sure you check mark the box next to your user that says exclude protection.
You should probably get in touch with your host's support team for these sort of questions.
Typically, you receive an e-mail that has your cPanel account name, password, as well as something like "Temporary Webpage URL" which you can use to access your website until your DNS resolves in the form of: http://127.0.0.1/~account.
The "account" in above url example is your user name of cpanel.
I am running a Perl CGI tool that executes a system command (Unix) which may run for a few seconds up to an hour.
After the script is finished, the tool should display the results log on the screen (in a browser).
The problem is that after about 5 minutes I get a timeout message "Gateway Time-out" - the system command continue to run but I'm unable to display to the user the results of the run.
In the Apache config file (httpd.conf): Timeout 300.
Is there a simple way ordering the Apache to increase the timeout only for a specific run?
I don't really want to change the Apache timeout permanently (or should I?) and not dramatically update the code (a lot of regression tests).
Thanks in advance.
Mike
Make the script generate some output every once in a while. The timeout is not for running the program to completion, but is a timeout while Apache is waiting for data. So if you manage to get your program to output something regularly while running, you will be fine.
Note that HTTP clients, i.e. browsers, also have their own timeout. If your browser does not get any new data from the web server five minutes (typically), the browser will declare a timeout and give up even if the server is still processing. If your long running processing gives some output every now and then, it will help against browser timeouts too!
For completeness:
Though the accepted answer is the best (it's variously known as KeepAlive packets in TCP/IP, or Tickle packets way back in appletalk days) you did ask if you can do dynamic Apache config.
An apache module could do this. Oh, but that's a pain to write in C.
Remember that mod_perl (and to some extent mod_python, though it's deprecated) do not only handlers but wrap the internal config in perl as well. You could write something complicated to increase the timeout in certain situations. But, this would be a bear to write and test, and you're better off doing what Krisku says.
There doesn't seem to be any way to specify a timeout on the <!--#include virtual=... --> directive, but if you use mod_cgid instead of mod_cgi then starting with Apache 2.4.10 there's a configurable timeout parameter available which you can specify in httpd.conf or .htaccess:
CGIDScriptTimeout nnns
...where nnn is the number of seconds that Apache will allow a cogitating CGI script to continue to run.
Caveat: If you use PHP with Apache, then your Apache is presumably configured in /etc/httpd/conf.modules.d/00-mpm.conf to use "prefork" MPM (because PHP requires it unless built with thread-safe flags), and the default Apache installation used mod_cgi with the prefork MPM, so you'll probably need to edit /etc/httpd/conf.modules.d/01-cgi.conf to tell Apache to use mod_cgid instead of mod_cgi.
Although the comment in 01-cgi.conf says, "mod_cgid should be used with a threaded MPM; mod_cgi with the prefork MPM," that doesn't seem to be correct, because mod_cgid seems to work fine with prefork MPM and PHP, for me, with Apache 2.4.46.
Although that doesn't give you complete control over server timeouts, you could specify a different CGIDScriptTimeout setting for a particular directory (e.g., put your slow .cgi files in the ./slowstuff/ folder).
(Of course, as krisku mentioned in the accepted answer, changing CGIDScriptTimeout won't solve the problem of the user's web browser timing out.)
Is there one? Apparently not. The H2 automatic mixed mode is described
here.
Revival for further reference.
As stated by #fredt, as far as I know, there is no official magic parameter to achieve mixed mode.
Still, you can always start a server programmatically using a Server object so that other process are able to connect to your database.
I discovery a trick to accomplish something pretty close to mixed mode. In order to do that you will need to set the remote_open property to true and connect using this form of URL.
The idea here is doing something like this:
Try connecting to the server using the kind of URL stated above.
If you can't connect it means the server haven't been started, so go ahead and start the server programmatically.
When you connect again, one of three things will happen.
If no database file exists, one will be created in the specified file path and the server will start serving it from the URL alias.
If the database file exists and it isn't being served, the server will open the file from the specified path and start serving it.
If the database file exists and it is being served, the server will simply return a connection.
I'm not sure if it is safe to use that kind of pattern when you plan to spawn a lot of short lived processes (particularly I haven't dive into HSQLDB code to check how it handles database / creation / opening for multiple simultaneous requests when remote_open is set). Still, I've been using this kind of pattern to share development databases between Web Applications for a while and never ran into a single database corruption problem.
The main limitation here is that when the application acting as a server is closed, open connections will stop working and throw Exceptions... Which is not an Issue for my development environment, here this will generally only means one or two broken requests until another server is started and the connection pool detects and renews its connections.
No HSQLDB does not support such a mode.