Alan Siu's Blog

  • HDCP error in Netflix using Safari

    If you try to play Netflix on Safari using an external monitor/projector (either mirrored or extended), you may get this errror: Whoops, something went wrong… Display Error There appears to be a display problem. Please ensure your monitor is HDCP compliant and is not mirrored using Airplay. For additional assistance resolving this issue, please visit…

  • Using text variables in tlist_sql queries in PowerSchool

    On custom pages in PowerSchool, you have the option to use something called tlist_sql to run SQL queries on your PowerSchool database. Sometimes, you can insert variables in your query. I’ve had good luck with SQL queries using built-in variables that are essentially a number: ~[tlist_sql; SELECT t.Name, to_char(st.Test_Date, ‘MM/DD/YYYY’), st.Grade_Level, ts.Name, ts.Description, sts.NumScore, sts.studenttestid…

  • Exporting a .csv of users out of Active Directory

    Even though I found many tutorials on how to export Active Directory users from a group into a comma-separated values text file, none did exactly what I wanted (specify an organizational unit, get only the active users, get the first and last name and the email address out). I had to do a little bit…

  • Toggle Allow apps downloaded from anywhere

    There’s a setting on Mac OS X for allowing apps to be installed from anywhere or only from signed developers. If you want to automate changing this setting via terminal command, this is how you do it. sudo spctl master-enable sudo spctl master-disable The spctl command is even more versatile than that. More details at…

  • Changing the error policy on a CUPS printer

    The default error policy for printers on CUPS (which Mac OS X uses, and which most Linux systems also use) is stop-printer. You can see information about your printers and error policies by looking at the output of the printers.conf file with this terminal command: sudo cat /etc/cups/printers.conf If you want to get the actual…

  • hdiutil: create failed – error -5341

    Usually if I have an .app I want to import into Munki, I just use munkiimport nameofapp.app, and Munki automatically creates a read-only disk image (.dmg) with the .app inside. For some reason, with the mBlock.app, I kept getting a 5341 error. I tried this workaround, but I still got the same error. What worked…

  • Using a terminal command to disable App Store automatic checks

    If you want to automate disabling the App Store auto check, the terminal equivalent of System Preferences > App Store > Automatically check for updates is sudo defaults write /Library/Preferences/com.apple.SoftwareUpdate.plist AutomaticCheckEnabled -bool false This is handy to know in case you’re managing updates a different way (e.g., Munki) and don’t want your users pestered with…

  • Creating a custom page in PowerSchool for a .csv export

    Even though teachers can easily get their own class lists out as an export from Gradebook, and you can also use DDE (Direct Database Export) to get such a list out after having selected the group of students, I thought it’d be nice to have a page that’s dedicated to get a .csv out of…

  • Making PowerSchool custom pages useful for sophisticated reporting

    If you don’t want to use PDO on a WAMP server to connect to and report from your PowerSchool database, you may still want to do some sophisticated reporting from PowerSchool’s custom pages. Unfortunately, custom pages is a bit of a coarse tool that’s also not well documented (in terms of sophisticated reporting—simple reporting has…

  • Using PDO on a WAMP server to run PHP reports from PowerSchool

    SQL Developer Queries General ODBC Access 🙁 WAMP and PDO Prerequisites Strongly Consider Using SSL Install Drivers Use PDO to Connect to Database This may be a niche setup, but I’m going to try to document it here, in case anyone else is interested in how this gets done. SQL Developer Queries If you are…

  • Licensing GSP Deployments with a Payload

    License GSP Deployments with a Payload Generally with licensed software, the trick with importing into Munki is to get the normal software imported and then import as an “update,” whatever needs to happen to get it licensed. Geometer’s Sketchpad works that way. So you import the Sketchpad app as you would any other. Then activate…

  • Preparing SonicWALL Mobile Connect for Munki

    I’ve found NetExtender (Packaging NetExtender for Munki) to be a little less buggy than SonicWALL Mobile Connect, but NetExtender is pretty much non-functioning in El Capitan, so I’m looking at possibly deploying SonicWALL Mobile Connect in the future. The import process into Munki for the .app is fairly straightforward. You install SonicWALL Mobile Connect from…

  • Disable auto-updates for Firefox when deploying using Munki and AutoPkg

    Note before you begin Acknowledgements Why you should do this The actual procedure Caveat Thunderbird The CCK2 method Note before you begin If you know nothing about Munki or AutoPkg, then this page will be of little use to you. If you’re interested in a basic setup tutorial, check out the Absolute beginner’s guide to…

  • Installing rEFInd on Mac OS X El Capitan

    If you’re using rEFInd on a Mac (for example, if you’re dual-booting or triple-booting with a Linux OS), you may have found rEFInd worked fine with Yosemite but broke with El Capitan. This guide worked for me to get it going again: Installing rEFInd on Mac OS X El Capitan.

  • Enable duplex printing via terminal command on a Mac

    If you want to enable duplex printing via a terminal command (e.g., trying to fix a bunch of already-installed printers with duplex disabled, and you want to fix that with a script), first you have to figure out what parameter to change. On one Mac with the printer installed, find the printer via System Preferences…