Archive for February, 2010

Inside the iMac

Hardware | Posted by attriel February 16th, 2010

So, first off — This week’s post was supposed to either be the next in the MySQL series or the followup to the profiling post with a visualization tool.  But I haven’t vetted the instructions for MySQL pt 2, and I need to get all the right screenshots for the tool discussion.  Sorry for that folks

Now, as for what this post IS!  Last week I had to change the hard-drive in an iMac.  The old one died, so it didn’t make sense to follow the general consensus of “just add an external drive and triple your storage it’s way easier”

Also, that kind of advice is just ANNOYING.

I did not, however, remember to take pictures.  Thought of it afterward, but I wasn’t opening the functional system just to do a photo shoot.  Here’s a forum post with links to videos and photos that I used for guidance

So, instead, I’ll explain it where I can.  Also, my system was subtly different from every example I followed, so remember: YMMV.  This was a 2006 or 2007 white Intel iMac

First off, I needed a 6 Torx screwdriver.  And the new SATA hdd.  Most of the recommendations suggested rubber cement or similiar for one of the later steps, I used my wife’s scrapbooking zots.

Step 0: Lay the mac down on it’s back, monitor facing up

Step 1:  Remove memory cover and memory modules (this procedure was explained on the base of the imac, for reference)

Step 2: Remove four torx screws from the bottom of the display; these are in line with the memory screws.

Step 3:  This step is hard.  While holding in the memory tabs, lift the case off the monitor.  The sides and face around the monitor are the part that you’re moving.  I believe in the end I took a small flat-head screwdriver and jimmied a bit to get it started so that I had something to press against to open it.  Also, once it opens a little, the memory tabs are held in by the facing, so you can move your hands to somewhere less awkward.

Step 4: Carefully lift up, bottom more than top.  Once you’re clear of the bottom of the case, keep an eye on the metal tabs and lift to bring them clear.  Also make sure you don’t pull too hard as that will mess up the iSight camera.  There should be enough play in the iSight to lean the case up out of the way

Step 5: There’s a black plastic wrapping.  Carefully pry this off around the bottom and sides (bottom was perforated and I had to break it to remove it, sides were sticky-tabbed).  At the top, above the monitor, you’ll need to carefully pry the black wrapping away from the top of the monitor, but not too far.  I again used a small screwdriver to leverage and slit along.

Step 6: In theory, all the directions said I could now lift the monitor off.  This was where mine went off the rails.  There’s a long black ribbon cable attaching something to the monitor.  I couldn’t see any way to detach it from either end, and I wasn’t willing to risk yanking anything.  So that limited how far I could move the monitor.  That’s along the middle.  On the left side, there are two sets of wires leading from the board to the monitor.  I unhooked the set nearest to me.  That gave me some play in the monitor for the remainder.  You can probably remove both and get more movement.

Step 7: I had to remove two screws from the left-hand side of the hdd.  There was a metal L-plate on that side, and it was hard to tell if the screws were for the HDD or for holding down the daughter-board.  Once you’ve removed those two, you can partially lift the HDD and pull it out to the left.  The right side of the HDD has a pair of pegs that slot into holes to stabilize, so you need to bring it enough right to clear that to remove.  But with the daughterboard in the way, you have to bring it up to clear the board.  It’s a little tinkering and magic to get both aspects.

Step 8: On the RHS of my HDD was a sensor, everything online suggests it’s a heat sensor, although I’m not really sure why they wouldn’t just use the SMART data the HDD has onboard, but whatever.  Carefully pry this off.  It’s glued, so you actually have to pry this one.  Remove the L and the pegs.

Step 9: Replace L & pegs onto new HDD.  This is where the rubber cement comes in.  I stuck a couple zots to the back of the sensor and applied it back to the harddrive.  I won’t swear it’ll stay properly, but I’m not having problems yet at least.  Slide HDD back in, screw back down.

Step 10: Replace monitor, reattaching the cables you removed (I only removed the one, so I was more cramped for steps 7-9, but I only had to remember which way one cable went in)

Step 11: Crimp the black plastic heat envelope back down and restick everywhere.

Step 12: Slide casing back on, hooking the metal clips inside the casing and being careful of the iSight cords & etc.  Hold in the memory tabs while getting the case over them.  Then carefully push the case on, squeezing it down as it gets near to done and starts to stick.  There shouldn’t be any lipping remaining, or the CD might not track smoothly

Step 13: Reapply torx screws.  Re-insert memory and close up.

Again, YMMV, and I really should have had pictures, because I know that when I was looking I wanted the pics to see what was being talked about.

Logfile Visualization

Tool Tips | Posted by attriel February 2nd, 2010

One thing I’ve been looking for, on and off, is some way to view a representation of the server logs in realtime.  Basically something I can take a look at and see what’s happening.  Also, playback at a later date to see what happened at a given time.

One of the only things I found that really did that was glTail.rb, a Ruby program.  I don’t have a lot of Ruby knowledge, so I didn’t go very far with it to see how it ticks and what I could modify.

It runs the log and streams bubbles from one side representing the server traffic.  Size is determined by request/response size.  I never quite figured out what the other set of streaming bubbles really represented, since Ruby isn’t in the environment I was playing in.  As a general use tool, it seems like it would be interesting if you had all the pre-reqs installed already.  As an industry tool, I wasn’t convinced that I saw enough benefit to justify installing the prereqs.

But I don’t think “industry level” even wants a tool like this, so !

I think the most telling video is the one discussed on the slashdotting page.