Fedora for short-lifespan server instances
Let’s come back to the odd fact that Fedora is both a precursor to RHEL, and yet almost never used in production as a server OS. I think this is going to change. In a world where instances are deployed constantly, instances are born and die but the herd lives on. Once everyone has their infrastructure encoded into a configuration management system, Fedora’s short release cycle becomes much less of a burden. If I have service foo deployed on a Fedora X instance, I willnever be upgrading that instance. Instead I’ll be provisioning a new Fedora X+1 instance to run the foo service, start it, and throw the old instance in the proverbial bitbucket once the new one works.
We upgraded our development server to Fedora 10 over the weekend. Among other things, it runs RT3 – excellent support, issue management, and bug tracking tool. Once the upgrade was over, we ended up with a semi-working setup of RT3. The emails were going through just fine, but the web interface was giving out a blank screen with no content or errors or warnings.
Googled a bit, but that didn’t help a lot. Went through server logs and found an out of memory shout from Storable.pm:
2325:Callback called exit at
../../lib/Storable.pm (autosplit into ../../lib/auto/Storable/thaw.al)
Googled for that, but it turned out that quite a few people have the problem with this module running out of memory. And not only in RT3.
So I left it where it was and had some good night sleep. And it helped. In the morning, englightment came in, and I tried reloading the page with cookies and cache cleaned. It worked. And then it didn’t work again. Cleaning cookies was helping for a couple of page views. So I dived back into the RT_Config.pm file to see my options. There it was.
C<$WebSessionClass> is the class you wish to use for managing Sessions.
It defaults to use your SQL database, but if you are using MySQL 3.x and
plans to use non-ascii Queue names, uncomment and add this line to
F<RT_SiteConfig.pm> will prevent session corruption.
# Set($WebSessionClass , 'Apache::Session::File');
Once I enabled Apache::Session::File, the problem went away. We are now back to work, enjoying the new web 2.0 round corners interface, pastel colors, and more.
A couple of years ago I went through all our (Olga’s and mine) printed photographes, selected the good ones, and ordered scans from the studio, so that I could have them all in digital form. One of the annoying problems I came across when catalogueing those images was the date.
Most images didn’t have any date reference what-so-ever, so I had to guess when it was or date these images as very uproximate. Others, did have a date added by the camera. The problem though, was that in many cases, the date was way off. That’s because the camera was never properly configured (users hate manuals).
Today, while importing images to Flickr I realized that the same problem applies to digital cameras too. Many images in my gallery had a really wrong timestamp in the EXIF data. Useless. Good thing I was keeping them in the directory structure, which referenced the date (2005/2005-04-15_My_birthday). I could easily fix it with a tiny script.
This got me thinking. How can the problem be solved once and for all? Is it even possible? Is there a way for digital camera to know what time it is, without user telling it? How about people who travel a lot – do they have to reconfigure their cameras at every time zone?
The travelling bit gave me an idea – GPS. Some cameras already use GPS to add geolocation coordinates to the meta data of the picture. But GPS receivers can be also used for maintaining the precise clock, which can be autoconfigured, and autoconfigured with time zone of the actual camera location. This is sweet!
Hopefully Canon (and other vendors who I don’t care about) already does it, or plans to do it in the nearest future. That could be an excellent technology application – useful, and invisible to the user. Just as it should be.
My brother passed by and fixed the damn thing. Now I can Skype with sound. From home. I wonder if I will be able to repeat the magic sequence at work. Probably not. But I’ll try.
I am really doing something wrong. Seriously. I can’t get neigther one of headsets to work. Headphones work just fine, both at home and at work. Microphones don’t. At work I can hear myself talking in the headphones, but I can’t record any sound and, obviously, I can’t use the headset in Skype. At home, I don’t even get the sound in the headphones.
I think I’m getting old… Oh, do I sound like my father now?
Shared bookmarks for del.icio.us user tvset on 2005-11-02
MRTG (Multi Router Traffic Grapher) is monitoring utility, which runs on many platforms and is capable of collecting and graphing statistical information such as network traffic, CPU/Memory/Disk space usage, etc. MRTG can gather information using both SNMP protocol and external scripts. Below are few pieces of my MRTG config file together with scripts, which I felt like sharing.
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