Sure, there are many DB monitoring tools out there, but Ignite focuses on tracking, analyzing, reporting, and explaining wait events within the database--and you'd be amazed how often waits caused by your code, that of others, or from other operations in the DB are the explanation for poor performance. It can help target exactly what SQL statement or other operation is a cause of significant waits.

The tool presents the data aggregated over time, so you can view it per hour, day, week, etc. Great for both drilling down to find hot spots, and for viewing how coding/config improvements (resulting from your responding to the analyses) have led to performance improvements over time.

The tool runs with low overhead: it reads data that the DB provides, storing it in a database and providing a web-based interface to view that data. The process to read the data and create the repository (and present the web-based interface) can (and should) be done on a server separate from the server being monitored.

Here's a nice 2-minute demo. There's also a free trial, of course, and it's pretty quick and easy to install and benefit from.

As I noted in the title, it works with SQL Server, Oracle, DB2, or Sybase (sorry, not MySQL. Don't know why). And while it's a commercial product, it's not a ridiculously high price (as for some tools). I just learned of it in the past few weeks, and one customer of mine who tried it has been just thrilled with the results. I hope to write more about it later, but wanted to at least get this info out for folks to consider.

Here's a screenshot of what you may see:

Note that this is not an error related to logging in. You do need to fill in a username to log into the Server Monitor, even if CF is set to only ask for a password when logging into the Admin. Just use "admin". This and other facets about the CF8 Server Monitor are covered in a 4-part series of articles I did in the Adobe Dev Center, starting here.

Confirming this is the cause of your Monitor challenge

From my observation, this error is related to a problem with the Flex client being able to talk to the server using a URL it needs to use, and the problem is web server related.

You can confirm if what I'm about to describe is your issue by trying to access the URL that the server monitor tries to use to access the Flex Gateway for CF, such as:

http://localhost/flex2gateway/

Actually, you should use whatever domain name/port you're using to access your CF Admin, which is then used when you ask it to open the CF8 monitor, which may be a URL like this:

http://yourserver/CFIDE/administrator/monitor/launch-monitor.cfm

Anyway, if that test attempt to open the /flex2gateway/ url comes back with a "file not found" (or 404) error, as opposed to a blank page, then you likely have the problem I'm describing, whereby your web server is mistakenly looking to verify that a file exists for the path you're specifying. You have 2 solutions.

First, let me note that this flex2gateway URL is not a file, nor a directory. It's a value intercepted by a servlet filter defined within CF. You need to tell your web server not to check for any existing file (it's trying to use one of the "default documents" that are used when only a path to the web server is provided.) Before launching into how to fix your web server, you may want to consider one other possibly simpler alternative.

Changing to use the Internal Web Server

Some will note that I've used no port above in the URL. That's why I point out for you to try whatever URL is used to access your Admin. In the case above (and the people who have reported this problem so far that I've seen, they've been trying to access the CF admin using their external web server, IIS.

If instead you were to use the CF internal web server to access the CF Admin, you'd have a port in the URL, like this:

http://yourserver:8500/CFIDE/administrator/monitor/launch-monitor.cfm

(or it could be 8300, or 8301: whatever is the port for accessing the built-in web server for CF, if you chose to implement that when CF was installed, and you are accessing the Admin that way.)

Well, I'd propose that if you DO use the internal web server, you probably won't get this error at all. The problem seems related to using IIS to access the Admin (and the CF 8 Server Monitor).

That said, I'll suggest that one quick solution folks can try is to see if indeed they can access their CF Admin (and monitor) using the internal web server. (If you can't or won't use it, I have the solution for getting it to work with IIS, in a moment.)

You just need to know what port to use to access the internal web server, if it's enabled.

First, may find that if (on Windows) you use Start>Programs>Adobe>ColdFusion 8>Administrator that it will open using the built-in web server. If it does, see if using that gets you around this whole problem.

If that opens it with external web server (doesn't use a port like those above), or if you aren't on Windows and have no Start menu, you can also get the web server port (and indeed enabled it, if disabled) by way of the jrun.xml file. Rather than detail it here, I'll point you to a couple of resources:

http://www.adobe.com/support/coldfusion/adv_development/config_builtin_webserver/ is an old technote, but the info still applies. Where it talks about disabling the internal web server, you'd want to reverse that, of course. There can be more subtleties and challenges to running the CF admin on the internal web server, if you don't configure it that way at the start, such as where are the /CFIDE files? Are they in the [cf]/wwwroot? or in your web server doc root, like inetpub/wwwroot? The built-in web server will look for them in the [cf]/wwwroot, so you may need to copy the CFIDE into this directory, or add a mapping to the built-in web server to point to the path as being located externally.

Making the change in IIS

Or you could just fix IIS to let you access the server monitor via IIS. The problem may be due to a setting in IIS (verify that files exist) that you may have caused to be set. (I don't know if it's set by default when CF is configured to integrate with a site, but I wouldn't think it was, so maybe this affects those who add new sites or configure things manually.)

And since this problem may affect other Flash/Flex apps trying to talk to CF, it may be worth doing for all such users. But this does come with a caveat to be aware of, if you might be using NTLM security to control access to files requested via IIS. More in a moment.

I offer the solution for IIS 6 and 7. I don't know if the same problem can affect Apache. If so, and anyone can offer the solution for there, please do comment.

Making the change in IIS 6

For IIS 6, launch the IIS Manager and select the web site which has the CF Admin you're trying to use. (It may be that you've also configured IIS so that ALL web sites are configured for CF, in which case this setting would be not at the site-level but at the root server-level, so you'd select the server name instead in the left IIS pane.)

From there, right-click and choose properties, and then select the "home directory" tab, then in the "application settings" area click the "configuration" button, and in the "wildcard mappings" section you should see something like "C:\ColdFusion8\runtime\lib\wsconfig\1\jrun_iis6_wildcard.dll" (which will be different, of course, for the JRun4-based Multiserver deployment).

This value is implemented here during the install of CF if you tell it to integrate with IIS, or by your running the CF Web Server Configuration tool after the fact.

Select it, and choose Edit, and if the "Verify that file exists" option is checked, un-check it. This setting can be confusing: you may think it means "verify that the named executable exists", but it doesn't. It refers to whether files requested and passed through this handler should be checked to confirm if THEY exist. Here's a depiction of the setting and how to get there.

Now try the URL above, and it should no longer give a 404. Then try again to login into the Admin. (Actually, you may find that you can just click the "cancel" button and it will login, even if the values for username and password are blank. I find this helpful when the CF server is temporarily unresponsive too, and the Monitor login screen pops up.) Hopefully the server monitor now works for you.

Note that this was NOT about changing the handler mapping for .cfm files, which also offers an option to control the "verify that file exists".

A caveat about access via IIS to NTLM secured files, and another alternative

Thanks to Mike Gillespie for the following notice and clarification. If you use NTLM security (windows integrated authentication in IIS) to secure files accessed via IIS, then you DO NOT WANT TO make the above change for your IIS site. I share below what he offered to me.

But I'd point out again that even with that issue, you could still use the built-in web server is a solution. Or, sticking with IIS, you could also create a new IIS site just for accessing the CF admin and monitor, and make the change above for that site only.

Anyway, if you do use NTLM security to control access to sites requested via IIS, consider the following:

The check that file exists option is required if you want to use NTLM perms to secure .cfm files. http://www.adobe.com/go/tn_18516 (Steps 1-4)

If you have a secure folder on your webserver put a .htm file and a .cfm file in it. Do not give your ID access to that folder. In IIS turn on clear text and NTLM auth.

With the "check that File Exists" option unchecked, try this test.

Try to access the .htm file in the browser - access denied

Try to access the .cfm file in the folder, - access GRANTED - so much for NTLM perms

Now check the box and try again (you will need to recycle cf and IIS)

Try to access the .htm file in the browser - access denied

Try to access the .cfm file in the folder, - access denied as it should be - but flash forms and server monitor are dead.

So "fixing" the Server Monitor problem on an authenticated server just broke the security of the server for the sake of monitoring... [frown>]

In a nutshell.

If you implement this so that CF pages can be authenticated against Windows Security http://www.adobe.com/go/tn_18516, then Flash forms break (and the server monitor too). So to get flash forms (and the server monitor) working, you have to implement this, which fixes flash forms (though every user gets their own personal file on disk on the server that has to be cleaned up) but it does not fix the server monitor.

It is the "check that file exists" selection that breaks the Server Monitor (and flash forms).

On a cf webserver that grants anonymous access there is no reason to check the "check that file exists" box. However, on a server that does authenticate users for NTLM file access, that box should be checked.

This section above was added after the entry was first posted.

The change for IIS 7. None needed?

For IIS 7, it's a little different. I actually run IIS 7 (Vista) and am not sure how/where the wildcard mapping equivalent got created (I may have fudged it manually), but it's now listed as a "Handler Mapping" (in the properties for a web site). In my case, it's labeled "AboMapperCustom-32635", but just look at those listed as handling "*" meaning all requests. It's listed with a value of IsapiModule in the Handler column. (If you're looking at a specific site, and the "Entry type" column says "Inherited", then there is another mapping at the server level, so select your server name in the left IIS panel, and repeat.)

Even so, I see no option to control "verify that file exists", so maybe this problem can't happen in IIS 7. I will say, FWIW, that there is indeed a an equivalent to that "verify that file exists" option, at least for specific extension handler mappings. Look a the one for .cfm, for instance. Double-click it to see its properties, and note a new button called "request restrictions". It has an option, "Invoke handler only if request is mapped to", and an option of "file". Again, though, this does not affect requests to non-cfm requests like that for the /flex2gateway/ URL.

About other Flex/Flash apps

As I said, it may be that the info above will help other Flex apps having trouble talking to CF (the CF8 monitor is a Flex app), but I'll note that this problem doesn't affect all Flex apps: only those that connect to CF via IIS.

For instance, on this same server where this problem occurred, there was never any problem using FusionReactor (which is also a Flex app). It was working fine the whole time. But then its default behavior is also to use its own Built-in web server, so requests weren't going through IIS. If I did try to use IIS to access FusionReactor, then it too failed (with a file not found), and the fix above solved that.

One problem: CF not responding

Someone asked for help on one of the Adobe forums, with a problem about users reporting that the server was not responding for extended periods.

After checking the logs (CF, Windows event, and IIS logs) and not "seeing anything to indicate errors", he wondered if somehow "you can set site availability windows".

I replied to him that, no, there are no features to set "windows of availability" for CF. So either CF was up and responding, or it wasn't. Even if it was, it may also be that his problem was with IIS. There are a few things that he could check.

First thing: check the Event logs for CF or IIS up/down

The first thing I'd do is check the Event Log (Application) to see if CF was indeed up or down. Look for event ids 3 and 4 for the "source" being the name for your CF server as shown in the event viewer.

Then I'd check if the web server itself may have gone down, using the same approach (though it's less likely). I'd also check the Event Logs (application or system) for any indications that the IIS application pool(s) may have have gone down. It's not unusual for the pools to recycle, but being down for an extended period may point out a web server problem (by which CF often gets blamed unfairly).

Next: Check the IIS logs

If that's not the issue, I'd then check the IIS logs, to see if indeed requests were being processed during that time. When people say "the server is down", that just means their requests were not processed. It may well be up and processing other requests. You'd also want to check whether cfm or other extensions were being processed at the time, their status codes, and the time-taken for each request (if enabled for the log in the properties for the site in IIS).

Next: Check the CF Built-in Web Server, if enabled

And when people report that it is "down", I'd also run requests using CF's built-in web server if it is/was enabled. If it responds on that web server, but not IIS, then that confirms a problem either with IIS or the web server connector between CF and it. The default port for CF's built-in web server is 8300, 8500, or some variation like it, depending on the version of CF and other things.

You can confirm if it's enabled and what port it would be by looking in the jrun.xml file. For more info, see resources like this CF 7 doc on the topic.

Using tools like FusionReactor, with even better logs

I'll point out that besides the web server logs, this is a problem that would be well served by having a tool like FusionReactor (fusion-reactor.com) and its great logging features that track all kinds of details about each page request. Of course, it's a great monitor and notification tool, with optional request protection features as well. (The CF8 monitor and SeeFusion are great too, but don't offer the kind of logs that FR does.)

Web Services specifically

He had also indicated that these were Flex apps calling CF web services that weren't returning data. He didn't indicate if other CF page requests were running, but since I've heard of problems of CF seemingly "down", the info above applies just as well to web service requests. As far as CF and IIS are concerned, those are regular requests, so they go through the same web server process and CF request queue.

(He didn't mention what version of CF he has--6, 7, or 8--and whether it's Standard or Enterprise. In CF8 Enterprise, there's a new feature to give web services requests their own set of request threads. You can see that in the CF Admin "Request Tuning" page.)

But he said specifically "during these times, calls to the web services never return any data". So, that's potentially still another issue. It may help to see what the web services would respond with if requested directly in the browser. Many don't realize you can request a CFC as a web service on the browser, which can help to confirm if/how it responds.

If you had a test.cfc with a method called getdata, that took an argument of myarg and a value of 1, you could request that on the browser using http://yourserver/yourpath/test.cfc?wsdl&method=getdata&myarg=1. If you need to pass in other arguments with simple values (text, numbers), just keep adding them.

Finally, you could also use a debugging Flash player or proxy tools like Charles to watch what traffic is going from/back to your Flex browser client. I list several such proxies in the CF411 resource I keep.

More help

There are surely still other things I could have thought of but I fired that off to see what he may say, and I've offered it here in case it may help someone. Feel free to raise questions here. (For anyone interested, the Adobe Forum thread this took place in was on here. If you want to offer something that may help the gent in question, feel free to reply there instead.)

I'll say in closing that if anyone has problems like the above and would like some help (someone looking over your shoulder to help you solve such problems), I'm happy to provide that sort of support, as discussed at carehart.org/consulting. But as you can see above (and in the forums, as well as many mailing lists), I'm also happy to share the info for people who prefer to solve problems on their own.