Sunday, February 27, 2011

Breaking KnowledgeTree

(For my own benefit also) In trying to aggregate some of the web servers I have deployed in VMs, I managed to break KnowledgeTree and had to re-install. On Ubuntu, it's a real P.I.T.A. At one point, I couldn't get past the following error:

Warning: include_once(DB/.php) [function.include-once]: failed to open stream: No such file or directory in /usr/share/knowledgetree-ce/thirdparty/pear/DB.php on line 371

The fix for the above is easy. It's usually an indication that there's extra kruft in the config-path file. To fix it, delete all of the lines in /usr/share/knowledgetree-ce/config/config-path except for /etc/knowledgetree-ce/config.ini.

Also, if you're working with the Chrome browser, you'll probably get into the condition where "control.php" downloads instead executing on the server. The point to remember is that even if you fix it, this condition will continue until to erase your browser history.

Yeah, it's been that kind of day.

Sunday, February 20, 2011

Playing with virtual tech

I spent a good portion of yesterday evening experimenting with various virtual technologies in an attempt to see what I could get running on my old HP desktop. The idea is that VMware is talking about discontinuing the paravirtualization feature in ESXi. I'm looking for an alternative to ESXi, preferably an open source one with a graphical management tool.

Note: I'm able to play with multiple technologies due to having a couple BlacX eSATA docks. In other words, I can experiment without overwriting the installed ESXi hypervisor.

The issue is that I bought the HP right when they started including hardware virtualization in commercial desktop systems. The problem is that the hardware is an early version of what's under hypervisors nowadays. The end result is a very finicky system. Some things work and some don't.
  • ESXi 4.x runs nicely on it, with more than a little driver customization (it took about 8 hours to get it working). This is the tool that I'm trying to move away from.
  • Proxmox 1.7 refuses to install.
  • CentOS 5.5 (required for HyperVM's use of Xen or Proxmox) installs but refuses to boot (even before installing HyperVM).
  • While Xen 4.0 does compile properly on Ubuntu 10.4.1, there's something wrong in the kernel that causes it to run very slow. It's well beyond my ability to troubleshoot (i.e., n00b).
  • Xen 4.0 on Debian Squeeze builds and runs nicely, but needs a front end for management.
  • XCP 1.0 installs nicely but also needs a front end. Also, the syntax is slightly different than regular Xen's, enough to be painful.
  • Citrix's XenServer installs nicely but is a commercial product
  • Virtualbox runs nicely but runs at the OS level.
  • KVM runs but I can't get the storage to resize and there's no good web front end.

Ignoring the learning curve, I've been spoiled by ESXi. The feature set just isn't there for most of the non-commercial offerings. I'll keep you posted on how it's going.

For now, you can list me as "still looking". In the long run, I'll probably settle on the Debian Squeeze solution. If anyone knows of a good web-based management tool for Xen 4.0 (running on Debian Squeeze), please let me know.

Friday, February 11, 2011

Just discovered a tool to extract some of the intelligence from the Twitter firehose: It appears to aggregate linked-to articles that people tweet about, focusing on a specific hash tag or stuff in your own tweet stream.

If you're reading my blog directly, in the "Daily Papers" menu to the right, I've added links to various "papers" for my "favorite" topics.

Saturday, February 5, 2011

Point of note

Point of note: it's not just Google's search results that Bing is "borrowing". The way MS describes what's going on, the toolbar will forward data from any search performed by the user.

For those looking to argue the point, you have to answer the following question first: Did (or did not) Bing "borrow" search data? Call it silly, call it nitpicking, I don't want to know what label you want to hang on the act.

In the end, they were caught doing something that equates to copying someone else's homework. They can't go to jail for it but I think the nun at the front of the class (the one with the firm grip on the yard stick) might ask 'em to hold out their hands...