Tag Archives: plug-in

Mac OS X Server Ubuntu Unix WordPress

WordPress Site Stuck In Maintenance Mode

When doing updates in WordPress, upgrading the WordPress version or the Plug-Ins causes the site to enter into Maintenance Mode. While in Maintenance Mode, a message appears that says “Briefly unavailable for scheduled maintenance. Check back in a minute.” rather than the actual site. Sometimes, especially if you’re using the automatic updating functions, an update might fail and the site may be stuck in Maintenance Mode.

WordPress looks at the root level of a directory for some hidden files that can tell a site to operate in a different manner. If there’s a file called “.maintenance” then the site will display the message above. When an update of a Plug-in fails, the .maintenance file is never deleted and the site is stuck in Maintenance Mode. To correct the error, simply ftp into the root of the site and delete the file. It’s hidden, so make sure your ftp software isn’t suppressing the ability to see a hidden file.

Whatever Plug-in or update failed likely also broke something. Usually, if it’s a Plug-in then you’ll need to re-install that plug-in, as the update process removes the old Plug-in and then adds it back. If it’s a Theme, you might need to re-install the Theme.

Programmatically, you can also enable Maintenance Mode by creating this file and then disabling Maintenance Mode by deleting (or renaming) the file again.

WordPress

WordPress and Spam Bots

There are a number of ways that you can protect your WordPress site from spam bots. The first is to only allow authenticated users to post comments. Doing so can still be a bit unwieldy, but this feature is built into WordPress and so pretty straight forward to use. Some, who deal with large amounts of spam bots then choose to completely disable the commenting feature outright (Settings -> Discussion -> Uncheck Allow people to post comments on new articles), but comments can still be made on existing articles and commentary is one of the best features of WordPress for many. To stop comments on older articles, also disable commenting on older articles (same page but also choose the Automatically close comments on articles older than option as well).

No site should have to disable comments or bend to the will of a spam bot. You can also then choose (same page again) to email the administrator when a comment is made and then choose to not publish comments until the administrator approves them. But spam bots will still attack, and now you’ll just get a ton of junk email. So many will turn to plug-ins for WordPress. There are a few of those that I like a lot. One is called Invisible Defender. Invisible Defender adds a couple of fields that are suppressed using the style sheets. These invisible comment fields, because they’re not displayed to a browser should then never be filled out. Therefore, if a field is filled out, it had to have been done by a bot. Those comments are then automatically blocked.

Then there’s the ability to force captcha (shows you funny garbled letters and you type them into a verify field). Captcha for account creation means that all but the most sophisticated bots will fail. This form of forcing an additional form of verification that a visitor is a real human can then be circumvented by users of OpenID, FaceBook and other services, using plug-ins that allow those users to be authenticated through the third party (typically requires a little theme customization).

Then there are the antispambee and akismet plug-ins, which look at the actual comments and attempt to determine which ones are spam. These make a good layer of defense but should not be the only layer used. Regrettably, any time you have user generated content on a web site you are going to have automated bots attempting to do a number of things, most likely sell black market pharmaceuticals and other items of questionable origin.

There are also bots that attempt to exploit the login page of the WordPress admin (<DOMAIN>/wp-admin.php or /wp-login.php. These are defeated an entirely different way. One of the best strategies is to lock out those who have attempted a number of invalid attempts that exceeds a threshold that you define.  Amongst those is Login Lockdown WordPress Security. Another layer for protecting the administrative side of the site is to add an .htaccess file to provide an additional layer of security on top of WordPress. You can also change the URLs of your login page, which I usually use a plug-in called Stealth Login for.

Finally, I like to back up WordPress in an automated fashion. There are a lot of plug-ins to do this, but I’ve always used WordPress Database Backup. Why? Because it works every time I tested it. I haven’t even bothered to test a good backup and restore for another software package because WordPress Database Backup always works, backs up data to another server I have, and it hasn’t failed me yet. I always test the restores of data that I’m backing up and I recommend that you test this (mileage may vary) if you choose to put it into production as well (false senses of security are in many cases worse than no security).

Home Automation Mac OS X

Running SSH on AppleTV

Sometimes it can be really useful to have an SSH connection into your AppleTV. If I need to explain why then you probably won’t want to do it. Unless of course, you’re just after getting something like Boxee running, which we’ll look at as well. Before we get into doing anything to your AppleTV, when we’re done I do not know how Apple will feel about your warranty moving forward, so do this stuff at your own risk (but that’s pretty much true for many articles on this site)…

So first up, let’s install SSH. To get started, plug in a jump drive you don’t mind reformatting. Then run the df command and look at which filesystem that the jump drive was mounted as. In most cases this should be /dev/disk1s1 or /dev/disk2s1 or something like that. Note this location and while you’re at it, double-check that the data is trivial to you and that you really don’t mind reformatting the jump drive.

Next, let’s download atvusb-creator, a little utility that will generate a new patchstick based on that jump drive (a patchstick being the term applied to usb sticks that will hax0r an AppleTV). Once downloaded, run the tool. Select ATV-Patchstick in the Choose an Installation dialog, and then select the version of the AppleTV OS you have (if you’re fully software updated then as of the date of this writing that would be 3.x). Next, choose ssh tools from the 3rd field in the Installation Options section, making sure that the box is checked. If you are just trying to get XBMC or Boxee running then you can check the boxes for those as well at this point.

ATV USB Creator Screenshot

ATV USB Creator

Next, set the USB Target Device field to be the filesystem you selected earlier and then click the Create Using button and wait for the process to finish. Once the patchstick has been created, plug it into your AppleTV and reboot the unit. You’ll see a bunch of code, similar to starting Mac OS X into verbose mode. When the screen tells you that you’re done, unplug the patchstick and reboot the device. Upon reboot it will be running SSH with a username and password of frontrow. If you’re not using a static IP address then if you open iTunes and connect to the device you’ll have an entry in your arp table for it. You can run arp and find the IP fairly easily. Once found, use the SSH command to connect to the device. For example, if mine is on an IP address of 10.0.0.100 then I would use the following command to connect to it:

ssh frontrow@10.0.0.100

Now you have an AppleTV running SSH. Even though this article isn’t meant to be about Boxee or XBMC, you can then install those by going to the new Launcher menu and then to Downloads and downloading those applications (otherwise if you try to access them you’ll get an error that the .app bundle can’t be found). Once those are in place it should open pretty easily.

Now that you’re running SSH, let’s look at one of the uses. I want a web browser on the AppleTV (even though typing a URL in it is pretty painful unless you install a keyboard too). For this instance, I’m going to use CouchServer, ’cause I like the way the keyboard works and because there’s a silverlight that kinda’ sorta’ works with it. First, download the files for CouchSurfer here. Then copy the files that were downloaded up to the device (assuming the filename is CouchSurfer-Lite.tar) from your client computer:

scp ~/Desktop/CouchSurfer-Lite.tar frontrow@10.0.0.100:~

Next, SSH into the AppleTV and extract the tar file:

tar -xvpf CouchSurfer-Lite.tar

Then move the extracted data into the PlugIns directory (which will display the appliance similar to how Launcher would be displayed at this point:

sudo mv CouchSurfer.frappliance /System/Library/CoreServices/Finder.app/Contents/PlugIns/

(your password will be frontrow in case you have hard core add and have forgotten it already)

We’re gonna’ give ownership to wheel:

sudo chown -R root:wheel /System/Library/CoreServices/Finder.app/Contents/PlugIns/CouchSurfer.frappliance

Then reboot the AppleTV. Upon reboot, you will then have a shiny new web browser making your AppleTV even more like a full fledged Mac with Front Row. Now you’re in pretty good shape. You’ve pretty much put more stuff on your AppleTV than you can possibly use, but you still probably just want NetFlix to work on it. For that, you’ll need to get Silverlight working with CouchSurfer and just browse to the movies in the web browser at Netflix.com as the Boxee implementation for AppleTV doesn’t yet work with NetFlix and there aren’t any native Plug-Ins that work with it yet either (that I’m aware of). Also, if you’re going to use any of the 3rd party media browsers, keep in mind that they’re sitting on top of the OS layer and that their resource utilization seems pretty poor compared to the native media browser on the device (given the abstraction there, it seems logical it would be so no complaints).

BTW, another fun little app (to help make your AppleTV more like your iPad):

http://code.google.com/p/weatherfront

And the most intriguing one that I haven’t actually gotten to work yet (haven’t had time to get past the second or third step – busy) is:
http://www.appletvhacks.net/2007/04/02/install-asterisk-on-apple-tv/#more-41

What I’d like to see – the ability to run my AppleTV as a Zwave controller… Or iPad… Or Newton… :)

Active Directory Mac OS X Mac OS X Server Mac Security

Mac OS X Directory Services Plug-ins

In a number of contexts, we hear about directory services plug-ins.  A directory services plug-in is a way for a Mac OS X computer to leverage the DirectoryServices daemon to obtain account information (be it authentication or policy information) from a server.  This might be an Active Directory server that uses the Active Directory Plug-in or an Open Directory server that uses LDAP.

You disable plug-ins that you don’t need and enable plug-ins (ie Active Directory plug-in or third party plug-ins) that you need in order to access directory services of various types.  These  plug-ins are developed in the form of .dsplug files.  The default plug-ins that Apple includes with Mac OS X are located in the /System/Library/Frameworks/DirectoryService.framework/Versions/A/Resources/Plugins folder in Mac OS X.  Any .dsplug file stored in this directory will be loaded as a plug-in, assuming it matches the parameters laid out in the DirectoryServices API.

By opening up the plug-in architecture (thus a plug-in rather than just a daemon) Apple has then left room for third party developers to provide solutions that supplement the tools that Apple has included in the operating system.  Thus, companies like Thursby, Quest, Likewise and Centrify have all provided ways of extending the usefulness of third party directory services.Third party plug-ins are typically installed in the /Library/DirectoryServices/PlugIns directory of a computer, which is where you will find plug-ins for Quest and products from Thursby.  Again, by virtue of a .dsplug being stored in this location the DirectoryServices daemon will load the plug-in.  Likewise chooses to store their .dsplug in the same place that Apple stores theirs, which is likely just accidental (although confusing when you’re researching how their plug-in works) – but the plug-in works just fine in either location.

You won’t typically run plug-ins you do not need.  Some, such as the Local plug-in cannot be disabled (then you couldn’t have local accounts to run services after all).  Plug-ins can be enabled or disabled in the Directory Utility, clicking on the Services icon in the toolbar.  When you do so you’re editing the /Library/Preferences/DirectoryService/DirectoryService.plist, either toggling strings to Inactive or Active (which seems like it should be boolean btw, but that is another story).  When a plug-in has been set to inactive the Daemon will skip loading it.  But it is still stored in the same place.  Because a plug-in’s active vs. inactive nature is stored in this property list we can then programatically enable or disable it using the defaults command.  For example, to enable the Active Directory plug-in you would use the following command:

defaults write /Library/Preferences/DirectoryService/DirectoryService “Active Directory” “Active”

Once the plug-ins are enabled or disabled we can then use them for authentication or for looking up Contacts assuming that custom search paths that include the directory service have been enabled and that we have properly bound to each, most if not all of which is defined very granularly elsewhere.  But suffice it to say that the plug-in architecture of Directory Services is well thought out and well laid out.

If you are interested in developing against the Directory Services API see the developer documentation here or you can access 10.5 specific information here.

Mac OS X Mac OS X Server Mac Security Windows XP

ProCon Firefox Plug-in Filter

Firefox users who wish to filter browsing (eliminate filtered words, etc) can use ProCon Latte, a Plug-in for Firefox.  ProCon is available at https://addons.mozilla.org/en-US/firefox/addon/1803 and can easily be deployed alongside Firefox.