High Tech Sorcery

Here is what I’m looking at:

• ISPConfig – been around a long time, seems quite mature
• Froxlor – an active fork of SysCP which has a decent reputation
• I-MSCP – a fork of ispCP which was a fork of VHCS which I know several people who supported

Packages can be found here:

https://launchpad.net/~agent-8131/+archive/ppa/+packages

Design goals:

• packages created for xen 4.0.1 and xen 4.1.0
• packages mirror install of xen as closely as possible
• currently only hypervisor and utils are included (make xen and make tools)
• no rc.d scripts setup, that’s left to user
• should be installable and functional on Debian and Ubuntu and on several versions
  • Debian lenny (hopefully), squeeze
  • Ubuntu hardy (hopefully), lucid, maverick, natty

Things to work on:

• getting stubdom to compile so pvgrub is present
• testing on various systems and fixing dependencies and conflicts as needed

I’m not an expert at Debian packaging but I’ve been gotten tired of building Xen on every systems and losing the advantages that packaging brings like tracking file conflicts.  So I decided to try and package Xen though I have had no luck so far.  I am making slow but steady progress.  I wanted to package both 4.0.1 and 4.1.0 so I could compare them.  I’m finding that 4.1.0 has stability issues and switching between the two without packages is incredibly time consuming.

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I took a development box running Xen 3.3 on Ubuntu 8.04 and upgraded in to Ubuntu 10.04 and installed Xen 4.1.0 from source.  I still believe Xen is the best open source virtualization solution.  At some point I’ll have to write up my experiments testing KVM + libvirt but suffice if to say the performance and stability were unacceptable.  However, while the performance of Xen is great, I have noticed some issues with Xen 4.1.0.

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I’ve been doing more work with linux traffic control.  I’m finding my earlier efforts are too complicated and end up introducing latency.  My latest shaper is very simple.  I decided I wanted to check in on the status of a couple of projects that can be used to classify p2p traffic.

• ipp2p – discontinued, recommends checking out opendpi: OpenDPI.org
• l7-filter – moved here: l7-filter | ClearFoundation

Though I’ve played with both of these in the past I’m not using either in production currently.  Most p2p programs are well behaved enough to mark data transfers as bulk which makes shaping easy.

Just some notes.  Of course one could use both.

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I had a client using postfixadmin but no one knew the password.  Simple enough to go into the db to reset:

dovecotpw -s MD5-CRYPT -p password | sed ‘s/{MD5-CRYPT}//’

Then in the database:

update admin set password=’CRYPTED PASSWORD” where username=’USERNAME’;

I found how to do this here:

SourceForge.net: Postfix Admin: Topic: Postfixadmin mysql password storage method

I’ve decided to expand this post a bit as I’ve run into a lot more problems.  I think I will try evaluating XCP 1.0.  Hard to imagine it being worse than Xen on Debian.

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http://www.devtrends.com/index.php/linux-console-modes-80×25-really/

I’m planning on buying/building a new computer and I think I will install Ubuntu 10.10 on it.  My plan is to use btrfs for the first time.  Risky, but I will be taking nightly backups.  However, Ubuntu 10.10 is planning on shipping with the Linux 2.6.35 which has a severe btrfs performance regression as documented here:

• Btrfs Did Regress Hard In The Linux 2.6.35 Kernel
• maverick btrfs slow install

But besides that I’m also hoping that the I/O performance situation will be improved.  It has been very difficult to track down where the bug is but I have certainly experienced it.  I haven’t tested the patches but if they work I hope they find there way into Ubuntu 10.10

• Fix “system goes unresponsive under memory pressure and lots of
  dirty/writeback pages” bug.
• Large I/O operations result in poor interactive performance and high iowait times
• The Linux Desktop Responsiveness Patches Are Feeling Good
• Heavy Disk I/O harms desktop responsiveness
• Very poor desktop response (high latency) during I/O-load with SATA+NCQ