Technology at Geneseo Community School District 228
The other day a storm came through and knocked power out for a good 8-12 minutes. Just long enough to get our server stack at the High School to shutdown. Anyways most servers powered back up okay but our Apache webserver/ MySQL server did a disk check and on reboot the MySql daemon failed to start. Looking into the logs it shows a message that the Innodb module failed to initialize and thus the mysql process crashes.
Looking into the specific mysql logs I find that this module fails because it the file innodb1 is corrupt. This is not good as this file holds the index and information for all databases on the server (300) and is used frequently. The easiest fix would be to restore a backup but in my case I showed the latest backup being May 5, 2013 and there has been two full weeks worth of activity since then.
To save all data and not relay on older backup need to try and force a recovery of InnoDB. According to MySQL documentation you can force a recovery by restarting the MySQL service/daemon after adding a line to its configuration.
[mysqld] innodb_force_recovery = 4
Under the mysqld section of the config file you can add innodb_force_recovery = 0 – 6.
Levels 1-4 are pretty safe as most data is preserved. Setting the level to 5 or 6 gets a bit more risky as you could lose some data.
In my case levels 1-5 did not good and MySQL refused to run. On force recovery level 6 the MySQL did work and all databases were up and running. After checking that databases (Spot checked about 50) and verifying no information lost, next step is to dump or backup all of the databases. When MySQL is in a force recovery mode other then 0, the databases are locked and you are unable to add information. You can however dump all the data as a SQL file export and then reimport the data to clean database.
Here I used PhpMyAdmin to select about 1/3 of the databases at a time. I learned the hardway to not select the Information Schema or MySQL database since if you do this, you cannot use PhpMyAdmin to restore your databases as it will fail on these two.
Do not select Information Schema or MySQL if restoring to same database server
With a backup of all databases minus these two safe and ready, now ready to reset MySQL and fix corruption.
My method: First make sure have backup, next stop the MySQL process running. Change the MySQL config file and set the innodb_force_recovery = 0 to zero then delete the innodb log files and innodb file itself(
iblogfile1 is a InnoDB logfile. ). Then delete (DROP all Databases except for MySQL and Information Schema).
Now restart MySQL and a new InnoDB and logfiles will be generated and you will have a working MySQL on recovery level 0 with no data. Now using PhpMyAdmin go to Import and Import all the databases back in MySQL and am back up and running. This process worked for me and no data was lost.
This afternoon I started a process of making 300 exact copies on a 2 gig flash drive. To copy a single disk at a time on Mac just using Finder was around 10 minutes. So at that rate we have 300 x 10 = 3000 minutes or 50 hours of copying. Not really going to work, I tried a few google searches for copying multiple disk images to USB on a mac and did not really find anything that would work quickly and efficient with USB disks. On the PC side there is a free application called imageUSB, program works perfect and does what it says.
Here simply created a image of the a perfect finished flash disk, then using multiple USB hubs plugin disk and whoalah now I can do 32 at a time at 12 minutes per copy cycle. This reduces total time to make 300 copies to just around 2 hours.
Using generic sub 15$ dollar 10 port usb hubs I setup two PC’s doing 11 on a laptop and 21 on a Desktop. This setup with two machines offset a bit gave me time to plug and unplug usb thumb drives. If you ever need to mass duplicate thumb drives ImageUSB works great.
Mass Copying in Action
The HP LaserJet 4250 (4350) is a solid fast printer with a long lifespan and has a good price per print. There has been an unfortunate trend with many new laser printers that add wireless and new air print or cloud print options, which are nice, but at the same time shortchanging the more important price per page and toner capacity. The LaserJet 4250 can use a 42x cartridge with a yield of over 20,000 copies, this cartridge retails for 200$ on Amazon (not generic HP OEM) which if you quickly do the math works out to 1 cent per copy. The printers are relatively easy to repair with a fuser that snaps in and out and rollers that do the same. The printer debuted in 2002-2003 and all 5 in the district are still working well, going on a +10 year lifespan.
I ran across a 4250 that had a horrible loud clicking whenever the user printed. This machine still was able to print but the clicking was exremly and made you think the machine was about to break apart. Looking inside the machine I found a grey dust all over one side of the machine after removing the fuser. A closer look reveals that the black plastic gear that turns the fuser is made of a weaker plastic and all of the gears get ground off. This means the gear is slipping when turning the fuser and snapping against what is left of this gear. Good news is a quick google search and this gear was found for under 10 dollars along with a guide on how to remove. Here is the guide provided with the gear on how to replace, the instructions worked well except I ended up having to drill out the screw holding the gear axle and epoxy it back in place with the new gear.
New Fuser Gears (5-10$)
Bad Gear – Notice the ground plastic shaving from the old gear)
Location of screw that holds worn gear, I ended up drilling it out.
I came across a strange issue where I was noticing an extremely high number of UDP sessions using port 8612. This is not a normal port for UDP traffic or any traffic for that matter so I wondered what it was doing. Taking a closer look it appears that an old Cannon printer finder application had been loaded on teacher and some student machines in the past. This little utility was located in
/Library/Image Capture/Support/LegacyDeviceDiscoveryHelper/ directory. Turns out in this directory I found this app CIJScannerRegister.app. This worthless little app just sends out broadcast UDP packets everywhere looking for an old legacy model Canon network printer. Here is the deal, on our network we don’t have a single Canon printer, let along a canon network printer. What ends up happening is 100′s of machines just send out endless broadcast looking for nothing, this is just noise and added network congestion.
To Remove I simply used ARD (Apple Remote Desktop) and did two quick terminal commands with root access.
The first command simply kills the process which is causing the endless UDP broadcast packets. The second command deletes the application so cannot start again on a machine restart.
rm -rf /Library/Image\ Capture/Support/LegacyDeviceDiscoveryHelpers
(Sending Command to Multiple machines – Remember must use Root account)
This greatly reduced the load on our Core switch during peak times.
Core Switch | Cisco show processes CPU command
Prior to stopping this rogue app / our core switch would hit CPU utilizations of 82-84%, with this app and all the useless UDP packets being stopped the core immediately returns to a more normal activity.
(Normal CPU Utilization for Core switch)
Over the weekend I changed out a battery on a HP MSA20 Raid device that houses data for Windows Active Directory based student directories as well stores copies of backups for a few servers. The system has functioned well over the last couple years but the battery failure caused data corruption on the that RAID channel. Luckily this data was easily restored from another source but I find it a design defect that a battery would cause the Raid to corrupt. Most Raid devices simply revert to a slow data mode disabling the write cache when a battery fails, this allows the device to still function and will go back to full speed when a new battery is installed.
On the back on of the unit you will see an digital panel indicating an error with either a F1 (lower batter failed) F2 (upper battery failed, or F3 (both failed).
The upper batter can be replaced by powering off the unit and removing the left side array. Inside is a battery back that takes a bit of fiddling to get removed from its casing.
I had to remove the unit from the Rack and remove a screw which held the left side Raid channel intact.
After Replacing the unit I had to hold the Power Button on the back and wait as unit did full boot. Battery pack was around 25$ .
The Sony VPL-EX4 projector can be problematic when replacing the lamp. This projector does not allow you to reset the lamp hours without entering the service mode first. Accessing the service menu is not including in the projectors documentation and they instead suggest contacting a Sony service department. This is silly since in normal day to day operation the lamp will only last 8-12 months (School setting), to be expected to contact a service person to put in a lamp and reset lamp hours with 30 projector units is not realistic. Epson printers and most newer projectors in general allow you to easily reset the lamp timer through a simple menu using the console or remote.
Okay back to the Sony VPL-EX4, to access the service menu you need to user the remote and hit ENTER | ENTER | LEFT | ENTER. This can sometimes be a bit tricky to take effect, it seems to help to be only 3-4 feet away almost directly in front of the projector when hitting the keys on the remote.
In Service mode press the enter key until you get to a screen that says System Protect ON. Here you can turn System Protect OFF then click DATA Reset and then restart the projector, this should clear out lamp hours. You can also do a Hard Reset but be warned that this will cause all of the color settings to reset to values that do not work well.
If you hit the Hard Reset and need to fix the colors here are the correct values in Order starting from the first screen of the service menu. Why these are not the defaults I have no clue but if you match your settings to mine below the picture color will look good.
Screen P1-1 (Notice you must turn ON a setting near bottom)
If you have an older SMART Board with a Serial to USB connector cable you may find that the newer version of SMART software does not support the device. This is because the SMART board Driver package does not include a 64 bit driver for this device and so the board will not attempt to connect. Luckily Smart did release a Windows and Mac driver for this specific style of devices but it is not included on the main webpage.
Here is the driver for the 500 Series SMART board Interactive Whiteboard Serial to USB cable. To install first install the latest SmartBoard software then install the package below.
SMART USB adapter cable (Part No. USB-FRU).
Here is a collection of free fonts I got off of dkfonts.com. It is a great website to find fonts but can be a bit painful if you are looking to install say 50-100 fonts. Here are 72 fonts that are good for Elementary Education and can easily be installed on a Mac.
EducationFonts (3 megs)
Here are some quick instructions on how to install on a Mac Running 10.8 (Instructions should also work on Macs running 10.5-10.7).
1. Download the file above and double click on it to expand the Zip archive. Now drag this folder to your desktop.
EducationFonts (3 megs)
2. Open Font Book, you can use Spotlight to find this program
3. In Font book go to the top and click File Add Fonts
4. Now navigate to your desktop and select the folder we just dragged there.
6. Lastly you need to restart your programs that use Fonts, or simply restart the entire machine and the new fonts will be present on Boot.
Lots of good Fonts, working on Handwriting, Cursive, great for worksheets.
If you have a MacBook Pro (2011 Model) with an Intel HD 3000 or HD 4000 integrated graphics card you may find that the Apple Bootcamp drivers and the latest drivers from Intel DO NOT allow you to connect via a Thunderbolt to VGA adapter to a Projector. If you find yourself on the Mac forums with this issue and having rebooted with connection connected, and having tried a variety of “fixes” with no success the answer is the Windows driver. You need a specific Intel HD 3000 driver which is no longer posted on Intel’s site but I did locate a working driver with same revision on Lenova’s website. I can confirm it works on the MacBook Pro 2011 running Windows 7 Pro.
Again this driver is actually from Lenovo but will work on MacBook Pro models 2011 models. It is the only driver revision that I have found that allows connection with Thunderbolt to VGA with any projector.
Strangely this specific driver revision has been pulled from Intel’s website. You can now only download the newer driver which does not work with all projectors / although it does seem to work fine with secondary LCD displays.
One issue that has been persistent in OS X Lion, it a strange problem in spacing when filling out a PDF Form. Basically the form will not space correctly to the next line and leaves a document with overlapping text. The current work around has been to double space as you fill out the form.
Good news as the latest 10.7.4 developers update appears to fix this issue. It looks like this update is slated for public release sometime in May.
Looking at Form that was filled using 10.7.3 version of Preview.
Looking at Same Form running Developers 10.7.4 version of Preview.