tzlee.com/blog

Author: Justin Lee

  • New glibc in CentOS 5.4 breaks VMware Server 2.x

    I’ve been puzzled for quite a while now why the web UI keeps crashing on one of my VMware servers here, and I finally decided to kick my lazy ass and get down to work.

    I found out that it was the vmware-hostd process that hosts the web UI ports (HTTP on TCP/8222 and HTTPS on TCP/8333). A quick search on Google gave me just what I was looking for.

    So it seems the new glibc version in CentOS 5.4 breaks VMware Server 2. If you’ve already upgraded your server, here’s how you can downgrade glibc:

    • Go to /etc/yum.repos.d
    • Make a copy of CentOS-Base.repo to CentOS-5.3-Base.repo
    • Edit CentOS-5.3-Base.repo and rename all the headings in the [brackets], e.g. [base] -> [base53]
    • Do a search and replace all $releasever with 5.3
    • Save the file
    • Run yum clean all then run yum downgrade glibc glibc-common
    • You’ll also need to re-run vmware-config.pl
    • After the downgrade is done, edit /etc/yum.conf and add exclude=glibc glibc-common glibc-devel glibc-headers glibc-utils nscd on a new line to avoid future update issues, at least until VMware decides to fix it.

  • Second Thoughts on the Apple iPad

    Before I slept last night, I thought, “Apple ain’t stupid.” They wouldn’t do something like not install OS X, so I went to bed, tossed and turned a bit, woke up this morning and saw some light.

    The iPad (urgh, I just feel wrong typing this name) is essentially a full screen touch device. Actually, they aren’t the first to build such devices. Tablets have been around for a while, and they weren’t very successful in selling. What was the problem?

    Windows. When Microsoft designed Vista, they had touch devices in mind, that’s why the sideways expanding Start Menu disappeared and was replaced with a scrolling design with larger icons. The user interface also had larger scrollbars and minimize/maximize/close buttons.

    But that was not the point. PC software was not built for touch devices in mind. Not that Microsoft designed Windows badly, but developers will naturally build apps for the larger majority – the regular PCs driven by a mouse and keyboard.

    So I think you get the idea now. Apple have had great success with the iPhone/iPod Touch’s software model and created the new multi-touch interface paradigm. They’re bringing this wisdom to the new iPad. If they had put OS X on this thing, people would go around installing regular OS X software and the user experience would be completely messed up – imagine hideous titlebars in the Aqua UI just so you can touch the minimize/maximize buttons.

    I’m going to bet my hard earned money on this one and buy an iPad when it’s launched.

    BTW if you read this post on Gizmodo, I’d agree no multitasking sucks, but the comment on the ugly bezel is irrelevant – you need a place to hold the iPad without interfering with the touch sensitive areas of the screen.

  • Apple’s new iPad

    While I really wished Apple didn’t name it iPad, it’s still too early to tell if this device would be any good. I was rather disappointed it didn’t run the regular MacOS X so I can have my favourite app – Terminal. Without Terminal, an Apple product is most likely useless to me.

    However the price point seems compelling starting at US$499, I’m estimating that to be SG$788 when it arrives.

    So what good is an oversized iPhone? It’s quite obvious Apple wanted the lock-in and screw developers around the App Store.

    I’m curious what Google has to offer as it seems I might be switching out of Apple to Android after the novelty of the iPhone wears off. I’d much prefer to develop in Java than having to pay for an ADC account just to write in a much more complicated Objective-C.

    On the books part, I’d gladly buy the Amazon Kindle. Unfortunately, I don’t have the luxury of time reading. I bought several books last year and about 80% of that is still sitting on my side table.

  • Little Code, But Still Complicated

    It seems like our app isn’t one that demands a lot of coding but is still quite complicated for a short development time span of two weeks.

    FYI, we are building an e-commerce app in Facebook with a different concept from Marketplace.

    Why do I say it’s complicated? Because it involves a lot of thinking and discussions to get the flow right. We have tiny bits of code here and there, each doing small little tasks. They don’t have much complicated code with maybe a few interesting SQL queries, but they are starting to add up to the overall complexity of the project.

    The other challenge is merging the 101 different technologies here. SQL, FQL, FBML, AJAX, PHP, REST, JSON… PIE, AYE, BKE, KPE, KJE, ECP… ayiah.

    Looks like we’re going to be spending more sleepless nights. Might have to forgo some features and the database tuning and indexing for now!

  • Curtains Up!

    Curtains and blinds are up! Actually was up about two weeks ago, but I didn’t have time to take photos, edit and upload. I finally found some time to do so. I didn’t take the blinds though, it’s pretty generic roller binds, though they are of much higher quality than Ikeas’. Photos can’t tell the difference in quality – you’ll have to see for yourself.

    The curtains are tailor made by Rosse Curtain and I would like to compliment them for their excellent service. The guy who installed our curtains and blinds was very detailed in his work and did his duty to keep the dust from drilling to a minimum. If you’re looking to get curtains for your new home, I’d highly recommend them.

    Living Room Curtains
    Dining Room Curtains
    Master Bedroom Curtains

    P.S. Choose your fabric wisely. They make a huge difference in price.

  • A Word On Amazon Web Services

    Today’s lecture was given by folks from Microsoft and Amazon. The Microsoft part was on the Imagine Cup 2010, a global student competition. I’m out of bounds already, so I won’t talk about that. 😛

    The most part was on Amazon Web Services (AWS). It’s pretty interesting how they had created a variety of products from technology and be able to monetize it, but I think the concept of utility computing is still at its infancy, or maybe early teens. The huge complexity here is the billing. Amazon bills for memory, CPU, disk, I/O bandwidth, etc. That’s a pretty exhaustive way to suck your money! I’d much prefer a billing scheme more like my mobile phone where I pay a flat rate a month and get billed some extras. While the aggressive billing ensures low contention on AWS, it is not economically viable for small companies to jump on it yet.

    There was a fair bit of discussion about pricing. Surely the sales folk looked uneasy and was all ready to stand up and defend himself, but let me add a few words in their defense – real bandwidth is expensive. A 1 Gbps “dedicated” link costs upstream providers like SingTel IX and StarHub IX an average of S$10,000 per month. We may find AWS slower here because of the latency we get transiting our Tier 2 providers (SingNet Broadband, StarHub MaxOnline) taking the cheapest (and thus longer) routing paths. We all think BGP is a distance algorithm, but in reality it can be easily manipulated using a technique called AS-prepend and policy-based routing.

    If you want to read about bandwidth, I wrote an old blog entry here.

    Most of our servers here load up slow in the US for this matter, so if you have a business that wants to reach millions around the world, you will probably not want to host it in Singapore, and when you start thinking of deploying overseas, manpower (or your time and air ticket) alone would make you think about switching to AWS instead.

    P.S. My angmor is getting from bad to worse. I didn’t realize I was writting terrible Engerish until I read some very old documents I wrote back during school days. This is what the working society does to you! Argh!@#!@