I'm migrating a lot of websites from Resin 3 to Tomcat 7 (centos 4/apache 2.20) and I'm struggling to determine what type of configuration matches my requirements. In particular:
proxy_ajp vs mod_jk vs mod_proxy for passing requests to Tomcat/Railo
automating deployment of new sites
putting WEB-INF outside the site roots (to simplify cloning sites)
using apache itk with tomcat so each vhost runs as a different user and process
having a single shared railo server administrator config
support for SES URLs with no extension (ie: /path/to/page)
SSL support required
I've read a lot of howtos already but most are out of date or provide conflicting advice. I would like to see some examples from people who run many railo vhosts and deploy them automatically or programmatically. In general I'd prefer efficiency/speed over simplicity as I want to get the most out of limited resources.
I could have asked these questions separately but I want to be sure any answers take into account all the above factors (assuming the requirements are actually compatible).
firstly, check out the vivotech installers - they are a hosting company, so use their installers as your base, they are flawless. (it uses tomcat)
railo 3.3 makes it a lot easier to deploy contexts from admin, so scripting this shouldn't be that hard.
web-inf should be automatically put into a site when it is defined in tomcat
if you give each user a new context-root, then they will have their own admin
every webserver (apache/iis2k8/even tomcat) supports url-rewrite
everything supports ssl
you might also want to look at how you're going to tune your jvm's for this senario, then do some load testing to see how they fare.
drop an email to sean corfield, google railo and his name and you'll get his email.
Related
I would like to setup mod_security as a stand alone instance protecting Tomcat instances against web application attacks. Would anyone know the pros and cons of doing this via installing mod_security as an Apache module versus installing mod_security on a reverse proxy? Has anyone implemented mod_security in either of these fashions? And if so is one preferred over the other?
There's really no difference in your two options. What non reverse proxy would you install the module on to protect Tomcat?
The question doesn't really make sense as they are both the same to you.
If you already have an Apache server, then you install ModSecurity in one of two ways:
In embedded mode by installing ModSecurity as module in the existing Apache instance you already have. The advantages are that you won't have to set up a separate Apache instance, and that the ModSecurity will have access to the environment that Apache runs under (so can see environment variables for example or log to same log files).
In a reverse proxy mode. This involves setting up a separate Apache instance, with ModSecurity on it only, and funnel all requests through it, before sending on the requests to your normal Apache. The advantages here are a dedicated web server just for ModSecurity, so you will not share resources with your existing version of Apache, if it is already resource hungry. Disadvantages are that it doubles your infrastructure and the complications that brings.
Personally I prefer option 1.
However, as you want to set up a dedicated web server in front of TomCat, the two options are identical for you. The new instance of Apache (or Nginx) that you set up will be running it in embedded mode and will act as a reverse proxy to your Tomcat server.
Personally I always think it's best to run a dedicated web server like Apache in front of any app server like Tomcat - especially on a public facing website. Granted Tomcat does include a pretty good web server (called Coyote), which may serve most of your web server needs, but a dedicated web server like Apache is more geared towards serving static content and contains other features for performance and security which make it a better end point server (including the ability to run ModSecurity for example!).
And just in case there is any confusion, Apache is actually short for Apache HTTP Server, and is sometimes called Apache httpd after the process that it runs. It is Apache's most popular bit of software hence why the name gets shortened, but Apache actually have lots of bits of software (including Apache Tomcat - usually shortened just to Tomcat).
I'm using a Debian VPS on DreamHost and wanted to install a feature-rich customer issue-tracking system (not for software development like Bugzilla). OTRS made my shortlist and I followed the Installation Instructions through the "Web Server Configuration" step (/etc/init.d/apache2 restart), but the restart step reported failure. Nevertheless pgrep apache showed it was running. In fact, it turned out that although www.mysite/otrs/installer.pl was running, my regular website showed a page claiming it had no content (but when I looked in the website's folder, its content was fine, just not being served).
DreamHost Support was very helpful, but explained that they don't use the standard Debian Apache server for hosting websites and instead use their own. Specifically, the Debian server is in /etc/apache2, but the DreamHost server is in /dh/apache2. DreamHost Support determined that the OTRS installation instructions were configuring the usual Debian Apache location which somehow prioritized that server instead of the DreamHost server. They tried moving the otrs.conf file into /dh/apache2, but though the regular website was working again, the OTRS page wasn't.
Has anybody had success installing OTRS on a DreamHost VPS?
I've consulted one of our admins on this, and these are our suggestions:
You will either need to:
Adapt DreamHost's Apache build to incorporate the OTRS modifications
Get Debian Apache up and running
Both options will require an admin user and some knowledge of Linux command line and Apache management tools. You will also need to set your VPS to UNMANAGED, which means that any changes in the DH Web Panel to any of your domains will have no effect whatsoever. Just make sure the DNS records for any domains are pointing to your server. You will also need to be able to manage your own Apache configurations.
NOTE: This will also essentially mean that DreamHost support cannot and will not troubleshoot your domains. Unmanaged means unsupported in any way!
There are a few core differences between DreamHost's apache2 configuration and the default Debian build. The first issue I observe is that DreamHost's configuration does not allow for extra configuration files to be loaded in the manner that the OTRS documentation suggests. This means if choosing option 1, you will need to manually insert the OTRS directives into DreamHost's configuration files, which may prove difficult.
I would recommend moving or otherwise disabling the /dh folder entirely after setting your VPS to unmanaged. This will not allow DH-default Apache to start when the VPS starts. You may also need to remove the DH Apache startup script in /etc/rc3.d/S02httpd2 and the actual script at /etc/init.d/httpd2.
Once you have your own version of Apache running successfully, you might consider copying the VirtualHosts that were previously at /dh/apache2/apache2-ps/etc/httpd.conf into your own domain configuration files in your conf.d directory, or you can shuffle your website files around and configure your Apache to your desire.
Once you've got your own flavor of Apache running, you should be able to implement the OTRS instructions per their wiki. :)
For a SaaS running on Node.JS, is a web-server necessary?
If yes, which one and why?
What would be the disadvantages of using just node? It's role is to just handle the CRUD requests and serve JSON back for client to parse the date (like Gmail).
"is a web-server necessary"?
Technically, no. Practically, yes a separate web server is typically used and for good reason.
In this talk by Ryan Dahl in May 2010, at 37'30" he states that he recommends running node.js behind a reverse proxy or web server for "security reasons". To elaborate on that, hardened web servers like nginx or apache have had their TCP stacks evolve for a long time in terms of stability and security. Node.js is not at that same level yet. Thus, since putting node.js behind nginx is easy, doesn't have many negative consequences, and in theory increases the security of your deployment somewhat, it is a good choice. At some point in time, node.js may be deemed officially "ready for live direct Internet connections" but wait for Ryan/Joyent to make some announcement to that effect.
Secondly, binding to sub-1024 ports (like 80 and 443) requires the process to be root. nginx and others automatically handle binding as root and then dropping privileges to a safer user account (www-data or nobody typically). Although node.js has system call wrappers in the process module to drop root privileges with setgid and setuid, AFAIK other than coding this yourself the node community hasn't yet seen a convention emerge for doing this. More on this topic in this discussion.
Thirdly, web servers are good at virtual hosting and in general there are convenient things you can do (URL rewriting and such) that require custom coding in node.js to achieve otherwise.
Fourthly, nginx is great at serving static files. Better than node.js (at least by a little as of right now). Again as time goes forward this point may become less and less relevant, but in my mind a traditional static file web server and a web application server still have distinct roles and purposes.
"If yes, which one and why"?
nginx. Because it has great performance and is simpler to configure than apache.
I've been trying to mug up on Glassfish and one thing that keeps coming up is the "how-to" on fronting Glassfish with Apache. Unfortunately, I have yet to find a description of why you would want to do this!
From my experimentation, Glassfish seems like a pretty fully featured web server-type service; but I might be missing a lot. So, is the notion of front-ending Glassfish more of a solution to integrate it with an existing architecture, or does front-ending (in a pure Java environment) provide extra benefits?
There's also another valid use case as to why we front Glassfish with Apache. Apache in this instance would function as a reverse proxy for increased security of your Glassfish. The RP is configured to allow only certain URLs to be passed through to the application server. For e.g., you may have app contexts /myApp and /myPrivApp deployed in Glassfish. In the RP server, you only configure /myApp to be passed to Glassfish. Anybody requesting for /myPrivApp would see a 404 'cos the request stops right at the RP level.
In one of my deployments, I have a bunch of WARs deployed, some for users coming from the internet, some for intranet only. I have 2 RPs running, one for internet users and the other for intranet. I configure the internet RP to only allow URLs for approved internet applications to pass through while intranet users get to see everything.
Hope that helps.
It is usually used to speed things up. Since apache is a very fast web server it is used to deliver static content. Like images, CSS files and so on. Glassfish serves the dynamic content (servlets, JSPs) in this scenario.
Another reason for using Apache as a frontend to Glassfish is the possibility to provide load balancing across a Glassfish cluster. See http://tiainen.sertik.net/2011/03/load-balancing-with-glassfish-31-and.html for details.
A other reason is that glassfish cannot run (easily) on port 80, without giving it root rights of course.
So, for most users it's easer to run a proxy (apache, nginx, varnish) some sort in front of apache and have both servers run under a normal user.
Then you have a other advantage of some configurations options of your front end. Like others mentioned, caching for example.
Recently our Software Analytic provider (NETTRACKER) sent us a plugin in order to be able to capture visitors in a better way. This plugin is for Apache 1.x and Apache 2.x. They said and I quote
that since Apache Tomcat is built on Apache HTTP server the configuration of the plugin should be the same.
I have looked for a httpd.conf in our tomcat deployment but we cannot find one, the only configuration that is similar to that one is the server.xml under the /conf directory.
If someone has better information regarding these two incredible products (Apache HTTP server and Apache Tomcat) I will greatly appreciate to draw the differences.
EDIT:
In case you are curious we know that Apache Web Server and Tomcat can work together using the mod_jk option and other proxys. But this will be too complex for our deployment.
Apache Tomcat and Apache HTTP are completely different server technologies. It is impossible to use a plugin for Apache HTTP server with Tomcat.
Apache HTTP server is developed in C and so are the plug-ins. On the contrary Tomcat is now completely developed in Java. Tomcat doesn't only serve static content, but it can also serve JSP pages and servlets.
Tomcat is used for hosting Java Web Applications. It can sure serve static content - you can host a web application using only Tomcat. Secure connections are supported and the performance is also very good (comparable with the performance of HTTP server).
A plain installation of Apache serves static content. Using the appropriate plug-ins, HTTP requests can be redirected to an application server (Tomcat, JBoss, Glassfish) or a script language interpreter (PHP). With this way dynamic content can be generated. The big advantages of Apache are the numerous plug-ins available, which allows administrators to configure and monitor web sites any way they want and that is the most widespread server available. This makes it the most secure solution, since it is thoroughly tested and any discovered flaw is corrected very quickly.
The best solution would be to use Tomcat proxied by an Apache server. It isn't so difficult to set up. If you can't do this, then you can't take advantage of Apache's plug-ins.
You see this confusion all the time. Many people think that Apache is a web server where in reality it is the name of an organization that has a web server project called "The Apache HTTP Server Project". In short the web server is called HTTPD (D as in daemon or Unix process).
Tomcat is another Apache project. This project implements a Java servlet engine to serve JSP pages and servlets. Tomcat and HTTPD have nothing to do with each other. However, you can set up HTTPD and Tomcat so that they work together. This way you can have HTTPD serve all static content, do URL rewriting and much more fancy stuff that the built in Tomcat web server can't do (or can't do very well). Whenever a JSP page is requested, HTTPD will pass the request on to Tomcat. Tomcat will process the request and will hand the output back to HTTPD which in turn will send it to the client.
Apache has many interesting projects. E.g. there is also a project called Geronimo which is a Java Enterprise server (J2EE). You can e.g. choose to embed Tomcat inside Geronimo to handle requests for JSP's and servlets where Geronimo does the more enterprisy stuff (LDAP, Messaging etc.). And you guessed it probably already, you can use HTTPD as a static content server for Geronimo as well.
totally bogus. Apache httpd plugins are written in C, Tomcat is pure Java.
Tomcat is a Java servlet engine. It can be hosted under Apache or IIS or quite a number of other external facing web servers. It sounds like you may be currently running your Tomcat instance standalone...
If you serve the JSP/servlets off of port 8080 and have it do things standalone, on the same host machine that Apache is running on, this can allow you to have them loosely coupled. Having multiple web servers fielding independent requests is not recommended, especially if you want to use server-based authentication along with Apache. Typically, you have one outside facing server that shepherds everything through it... Apache does this quite well, and the plugin you mention probably relies on this type of setup (everything gets wired through Apache) for its features/capabilities, based on your brief description of it.
If you would like to serve up your Tomcat servlets under Apache, you could configure apache to forward a class of URIs to your tomcat server instances. you could achieve this type of forwarding through mod_rewrite. this is a slower option performance-wise, as it adds slight overhead on everything you server up. You could also proxy incoming requests via a CGI mechanism similarly, from Apache to Tomcat.
mod_jk will simplify deployment and increase performance for placing Tomcat into an Apache server config. It is pretty painless to configure if you follow the docs, so I am not sure what you mean by "too complex" for your deployment -- if you want Apache and have Tomcat already, it would seem only a matter of slight config changes to get mod_jk downloaded and installed.