พอดีลองวนๆ ไปหาอะไรอ่านเกี่ยวกับ project ที่ RH ดำเนินการอยู่พอดีไปเอะใจตรง SystemTab project ลองไปไล่ๆ อ่านดูทำไม concept เหมือน DTrace เลยหว่า

ลองอ่านๆ ในส่วนของ architecture ดูอืมม ไม่เหมือนแค่ concept ด้วยเห่ะ ทำงานยังคล้ายๆ กันเลย ใครสนใจลองไปดูได้ architecture paper (July 2005)

จำไม่เคยได้ซักทีเกี่ยวกับ find command แปะไว้กันลืมเจอมาจาก http://www.wagoneers.com/UNIX/FIND/find-usage.html

sudo find / -type f -name *.jpg  -exec cp {} . \;
 
find . -type f -size +10000 -exec ls -al {} \;
  

I was asked to analyze performance of an ERP working over Internet via OpenVPN. It works very well on local area network. However, it is pretty slow for remote access via VPN. The server is placed behide an ADSL router connected at 1024/512 and other endpoint are connected to another ADSL router connected at 512/256. Since there are many clients, I don’t sure what the bottleneck is. There are 2 possible points.

Sometimes you might need to choose the best FTP daemon to run 7x24 on your host. As of 5 years ago, I might say wu-ftpd is the most famous and you should use it. Unfortunately, as the time goes by, because of its popular, wu-ftpd was targeted to be hacked again and again. And then everyone seems to recommend to use SSH instead since there was no good enough alternative solution at that time.

Nowadays, I have to choose again. I found out that ProFTPD is one of the most popular FTP server for Unix server especially hosting service provider. As far as I know, Plesk includes ProFTPD as a standard FTP server. There are so many advanced features come with standard build of ProFTPD. Everything are customizable just like Apache HTTP server. In particular, ProFTPD supports virtual domain. That’s why Plesk chose it.

Pure-FTPd might not be the best FTP server but it is my most favorite one since yesterday. Its advantages are as belows.

• Easy
• Simple
• Fast
• Secure

It is enough for me right now. In addition, it is available on most distributions including Ubuntu. Unfortunately, it seems Pure-FTPd is too secure in term of compile-time options. The binary package of Pure-FTPd on Ubuntu 5.10 Breezy doesn’t support large file operation. As a result, I can’t see or transfer files larger than 2 GB. Oh, my god! Then I managed to rebuild the package again locally to support large file. Below are my instructions. Note that I am just a newbie for Ubuntu, Debian-style package management. This is a good practice for me.

Okay. Let me clarify a few things first. My favorite BitTorrent client is BTQueue for sure. I have never wanted to run other BitTorrent client especially on hosts placed in data center. BTQueue is the best candidate to run on server-class machine for remotely controlling through the Internet. Anyway, my friend didn’t think so. He had a machine running Windows 2003 because he like to use mouse to control everything instead of just a keyboard like me. This machine has been placed at a data center to run Azureus for him and then transferred files back to his home via FTP. Everything worked fine except only the bad sectors. Sometimes, the machine hung up without any notification. Then he checked all drives to ensure their healthy. In contrast, this machine has 3 drives, a IDE and two SATA. As a result, he found bad sectors in all drives, the most of them were existed in the IDE drive which is the system drive. This situation should not happen because all data are set to store in the two SATA. However, he claimed them all. Unfortunately, he had to claim some of them or all of them every 2 months.