Igmar Palsenberg's blog » JDI

Migrating from Xen Citrix to RHEV

Igmar Palsenberg — Thu, 28 Oct 2010 12:53:13 +0000

Since I’ve got fed-up with all Citrix bugs (operations that het stuck on locks, resumes not working, etc) and the fact that the’re probably going to drop Xen in favor of Microsoft Hyper-V we are going to migrate to RedHat RHEV.

The software installs fine (except for the know issue that you can’t register on RHN), but migrating 35 VM’s is not something I really like doing. Well, virt-v2v comes to the rescue according to the docs.

Uhm.. Well… not exactly. What the docs don’t really mention that it depends on a Xen with libvirt on top of that. And that is exactly what Citrix Xen doesn’t use. So, only errors, and no migration.

So.. I’m stuck with a manual migration, using or friends dd and netcat. Bah

PHP and the reasons why we consider switching

Igmar Palsenberg — Mon, 13 Sep 2010 13:28:59 +0000

PHP is a nice language, with numerous advantages :

Easy to learn
Easy to install and upgrade serverwise
Interpreted, so no compile and deploy worries

The disadvantages are starting to annoy me more and more over time :

Zend engine is huge. It’s a major memory consumer
Not all extensions are stable. When it comes to thread safety, there are major problems
Some language constructs simply suck : __construct(), the 5.3 namespace seperator
No type hinting for build-in types (int, string)
No OO function overloading
Multibyte support is basically non-existent

Our current framework (I-Content) is based on PHP4 code, and therefore not object orientated. There are some improvements, but the PHP limitations don’t go away.
Our new framework is on it’s way, and build using JAVA. The above limitations go away, althrough we get some new disadvantages in return. Time will tell if the switch is really going to happen…

Booting a > 2 TB partition using EFI

Igmar Palsenberg — Fri, 20 Aug 2010 14:43:52 +0000

When our new storage server arrived last week, I wanted to skip use EFI t0 boot this system. It requires en EFI capable system, which this Intel server mobo is capable off.

The CentOS installer doesn’t grasp an GPT partition table (needed to enable > 2TB partition tables), so I installed manually. Well.. That didn’t go to smooth. Manually installing CentOS, and the GPT partition table was, looking at it afterwards, the least of my problems.

Booting the system was. The system was throwing me into an EFI shell, instead of booting the system. After doing some RTFM on EFI the issue became clear : The EFI BIOS wasn’t seeing the controller, because the BIOS on the Areca RAID card isn’t EFI capable, but only supports plain old BIOS.

End of story. Areca isn’t going to provide an EFI BIOS, because no OS supports it. No OS supports it because no EFI BIOS is avaiable. You get the point… So, back to a plain old MS-DOS partition table.

Migrating to SSO

Igmar Palsenberg — Fri, 23 Jul 2010 08:15:45 +0000

We at JDI are moving to a project based working method. We decided to use the tools from Atlassian, since those tools seem to do what we require. We also run a number of internal tools, and all those together mean remembering about 6 different usernames and password.

We decided to give Crowd a try : SSO, with an option to integrate with custom applications. It uses SOAP internally, and SSO is managed with a domain cookie. About a day work, but now all Atlassian tools we use, our administration system and subversion are authenticating against crowd

We’re at Maildir now

Igmar Palsenberg — Sun, 11 Apr 2010 20:59:59 +0000

As noted in this posting, we migrated to Maildir. It went relatively smooth, and faster then anticipated. I’ll be posting the code to the actual migration script (41 lines of PHP code), and the code code to the milter that temporary locks the mailbox (aboyt 150 lines of C actually written by me). This way, it reduced downtime to the actual time needed to do the conversion, instead of shutting down the whole MTA.

The source for the PHP script and milter are here.

Moving from mbox to maildir

Igmar Palsenberg — Fri, 12 Mar 2010 07:39:54 +0000

I’ve decided that it’s time to move from mbox to Maildir. Mailboxes are getting larger every year, and so serverload continues to increase. During scheduled maintenance the end of March, I’m converting all mailboxes to Maildir format.

I’ve run into a number of issues during some preliminary tests :

- The conversion can’t hand the situation that mail get’s delivered during the conversion
- IMAP / POP mutations on the mailbox while converting screws up the conversion process.

The IMAP / POP3 part can be handled the simple way: Lock the user during the conversion, then re-enable user after the conversion is done. The incoming part is a more challenging issue : You don’t want to shutdown the mailserver during the while conversion. You can’t tell sendmail to delay mail during a certain time by default.

To solve this, I’ve written a milter (see www.milter.org), so that during the RCPT TO phase, it checks the user’s homedir for a .maildisable file, and echo’s the first line of that file if it exists with a 4xx error. That solves the problem

Finding a new editor

Igmar Palsenberg — Thu, 25 Jun 2009 09:36:49 +0000

We, at JDI, are used to working in vi. When we started 11 years ago, most IDE’s wheren’t existant, and with 3 people with their own OS and configuration developing locally wasn’t an option. So we just shelled in, vim’ed all of our files, and created nice things that way.

Today, when the compay has grown, this isn’t an option anymore. People want an IDE, mainly for code completion and debugging. We run multiple OS’ses (Windows, Linux, Mac OS), so everything windows-only isn’t an option.

I’ve looked at three options :

Zend Studio for Eclipse
Eclipse
Netbeans

Zend studio is buggy, especially when it comes to Remote Systems. Not to mentions it’s slow as hell when it comes to importing a remote project. Eclipse suffers from the same problems, and NetBeans is missing remote SFTP support.

I’m trying Netbeans with MacFusion at the moment