So, the iPad turns out to be a shiny new thing that’s somewhere between an iPhone and a Mac… but (perhaps unfortunately) rather more iPhone than Mac. I was personally hoping it would turn out to be a desirable alternative to a netbook. In some ways, I can see that it has achieved this. It has great battery life and seems like the sort of shiny, handy thing you can easily just pick up and put down as needed to surf the web, check email, etc. Its possibilities go way beyond possible netbook replacement, though. For example, I think it will be desirable in corporate and education environments for taking notes, reading texts, doing presentations, etc. And of course its primary purpose seems to be as a media consumption device for various types of content you’ve bought through Apple’s retail network. No doubt it will fit into even more possible roles as Apple develop it further and as third party developers race to produce all sorts of weird and wonderful new apps for it. So I think it has a lot of potential, and plenty of people will buy it for all sorts of reasons.
For some time I’ve been having problems monitoring disk and RAID hardware in CentOS Linux on our HP ProLiant DL360 G5 servers. To begin with, I discovered that hpasm, the main monitoring agent provided by HP, does not actually give any information about the disks or the RAID controller, even though it does seem to monitor all other hardware in the server.
So, to monitor the disks, I started using smartd, which is part of the smartmontools package and comes with the CentOS distribution. This software uses the SMART system to attempt to predict when disks are going to fail. It’s quite easy to configure. For example, here’s the /etc/smartd.conf file I created on one of our servers which has six SAS disks arranged into a single RAID 5 partition. This should cause smartd to email me as soon as any problems are detected with any of the disks:
/dev/cciss/c0d0 -d cciss,0 -a -m email@example.com /dev/cciss/c0d0 -d cciss,1 -a -m firstname.lastname@example.org /dev/cciss/c0d0 -d cciss,2 -a -m email@example.com /dev/cciss/c0d0 -d cciss,3 -a -m firstname.lastname@example.org /dev/cciss/c0d0 -d cciss,4 -a -m email@example.com /dev/cciss/c0d0 -d cciss,5 -a -m firstname.lastname@example.org
Unfortunately, smartd doesn’t actually appear to be all that useful. It starts up fine and indicates via syslog that it’s monitoring the disks, but we’ve now had two disk failures on our HP servers, and neither time did smartd give any warning whatsoever about the failure. I only found out about the failure each time because I saw the orange warning light on the disk when I happened to be at the data centre – really not ideal!
I therefore went back to HP and decided to figure out what software of theirs I would need to use to do proper RAID/disk monitoring. HP Technical Support were predictably useless, telling me I needed to install the ‘System Management Homepage’ and a whole load of other bloated nonsense that I really didn’t want taking up resources on our servers. Some googling quickly revealed what I actually needed, which was the hpacucli RPM, which comes in the HP ProLiant Support Park (‘PSP’) alongside various other things including the RPM for the hpasm agent I mentioned above (which annoyingly seems to have been renamed to hp-health; I wish HP wouldn’t keep changing names of things unnecessarily because it’s already confusing enough trying to keep track of their software). The PSP can easily be downloaded from the Support section on HP’s website and is available for a variety of Linux distributions. The hpacucli RPM is easily installed in the normal way (
rpm -i etc.) and, once installed, you should be able to get information about the current status of your RAID setup with something like this:
hpacucli ctrl all show status hpacucli ctrl slot=0 ld all show status hpacucli ctrl slot=0 pd all show status
That command should provide output similar to the following:
Smart Array P400i in Slot 0 (Embedded) Controller Status: OK Cache Status: OK Battery/Capacitor Status: OK logicaldrive 1 (341.7 GB, RAID 5): OK physicaldrive 1I:1:1 (port 1I:box 1:bay 1, 72 GB): OK physicaldrive 1I:1:2 (port 1I:box 1:bay 2, 72 GB): OK physicaldrive 1I:1:3 (port 1I:box 1:bay 3, 72 GB): OK physicaldrive 1I:1:4 (port 1I:box 1:bay 4, 72 GB): OK physicaldrive 2I:1:5 (port 2I:box 1:bay 5, 72 GB): OK physicaldrive 2I:1:6 (port 2I:box 1:bay 6, 72 GB): OK
That seems to do the trick nicely, then. Even better, I found an easy way of integrating it into Nagios so that we’ll get notified the second anything goes wrong with any of our disks or RAID hardware. This was just a case of downloading the check_hparray plugin and configuring it accordingly. (I’m not going into the Nagios configuration here because it’s pretty well documented, and anyone administering a Nagios system should have no problem working it out.)
So there we go. Proper RAID/disk hardware monitoring and alerting in CentOS on HP DL360 servers with minimum hassle and no unnecessary bloated software.
Edit: this post was originally written for CentOS 5, but I believe it should work fine for CentOS 6 too.
In this book there seems to be very little in the way of consciousness getting explained and a lot in the way of Dennett trying to demonstrate how incredibly clever and witty he is. It’s agonising reading. He makes the same points over and over again so many times that I had to struggle not to throw the book across the room on several occasions. Dennett will happily produce ten pages of waffle for something he could easily have explained in two sentences. I have to admit that it didn’t take long before I started skipping past paragraphs, then past pages, then past entire chapters.
Using my charts on Last.fm, I’ve just made a list of my top 20 most listened to tracks of 2009 (well, of the last 12 months to be precise, but that’s near enough). I’ve ignored all the Dicepeople tracks because I listened to those hundreds of times whilst mastering my album so those don’t count. Also, to make it more interesting, I’ve skipped over tracks by artists that are already higher up in the list.
For some time I used my Novation Supernova II as a master keyboard, but then I got fed up with one of its keys not working, and I’d also bought a few new synths which were taking up space, so I moved it out of the way. None of my new synths were suitable as replacement master keyboards, however, so I decided I’d like to get a Novation MIDI controller with Automap for that purpose. I’d heard that these were great keyboards and that Automap was a powerful tool which made it possible to easily control DAWs and plugins from the controller without having to use the mouse (for example, my friend and music technology expert Robin Vincent wrote a blog entry about his positive experiences with a Novation Nocturn). The only thing concerning me about this was that I’d previously tried out the Automap app on my iPhone and found it to be inelegant and almost totally useless, but I decided that must have been a blip caused by Novation’s lack of experience on the iPhone platform.
I started playing Halo almost three years ago. I almost got to the end but then stopped playing for reasons I’ve now forgotten. Last weekend, however, I reinstalled it and finally completed it. It was a pretty thrilling ending and it felt great when I got to the end. It really is a superb game, and the part where the Flood first appear is undoubtedly a classic moment in the history of computer gaming, and certainly not something I will forget in a hurry.
I liked the fact that I played Halo on a Mac because it’s the spiritual successor to Marathon; if Microsoft hadn’t come along and hijacked it, then Halo would very probably have started life as a Mac game rather than an Xbox game.
I should be getting Bioshock tomorrow and I’m very much looking forward to that. We Mac users don’t get a huge amount of games but we do get a few good ones. In a way that’s better for me because I don’t get time to play many games, and thus I quite like having a small range of high-quality games available to buy instead of a bewilderingly large amount of stuff.