Study Notes

Kmail is the default mail tool in Mandriva’s KDE interface. There was something wrong with sending mai to other whose mail address is not belong to powerleader since last days when I used SuSE 9.1 Professional. I could only send mail to powerleader mail group.

The following steps could be used for resolving this problem:

Kmail – Kmail Configuration – Account – Modify – Sending mail – General Setting, the “Server authorize” option must be choose. and in the Secret Setting, we should use “Login” to identify the usename. All the three screenshot will be pasted in my collection.

Error messages:

Sending failed.
Connection to host … is broken.

The message will stay in the “Outbox” folder untill you either fix the problem.

iptables: administration tool for IPv4 packet filtering and NAT.

# iptable start
# iptable restart
# iptable stop

In Alief board, the customer installed Windows 2000 server, and then input an USB device. The windows could recognize this USB device normally. But when the system is reboot without taking out the USB device, Windows server processing stopped after a while. So dose this issue happen in Windows Server 2003.

Intel Engineer said that BIOS P10 could resolve this problem, through this latest bios is still not released by Intel. I’ve given the P10 bios to Haihong Chen and told him how to use it in Hainan.

There are so much trouble in Alief board and its platform recently. Another Alief board ‘s statues LED near network device are always blinking. When I reflashed the BIOS and FRU/SDR, LED is stable and everything is OK.

Good sleeping from 13:00 to 18:00 makes me feeling very well. I’m very tired last week for paying much attention to trouble resolution. Next week, I’ll update my work diarys and do with Hainan customer’s Alief issues since the service engineer Chen Haihong would have been there tonight. Chengdu’s Westville matter should also be watched.

In SuSE professional 9.1, crontab’s backup file is located at “/var/spool/cron/tabs/user”. If the crontab file is lost, just copy out the backup file and rename it to instead of the original.

My office application computer is installed Mandriva 2006, This afternoon, Tang brought me a CM8457 PCI sound card. The operating system recognized this device immediately, and shows me the following message in the screen: Input the second Installation CD 2 to install the Gstream package. I’ve done this step, and then open the Mandriva’s multiplayer Amarok to play a wmv file, It seems no picture was displayed but sound was set out.

Inter server board SE7520AF2 is the most powerful in the Dual Processors series. Hainan’s customer need this board installed in SC5300BRP chassis. In our factory, we put the AF2 board in the SC5300 chassis, added a 20320 SCSI card, and then the workers had tested this platform. Both two ethernet devices, Marvell and Intel 82541 was found in the operating system which is Windows 2000 advance server and BIOS menu.

It seemed everything was ok and this machine could be shipped out. At the final step before it was carried out, the IQC guys told me that the two ethernet devices were disappeared in the BIOS and operating system. I tried to re-flash the latest BIOS and Firmware. As the result, the ethernet devices were still not found. For the time of shpping out, we had to change another AF2 boards. The changed board was sent back to Intel 800.

Maybe one weeks passed, the customer called me and said that they could not find the ethernet device. I was surprised by this issue. The customer even could not see the Network device in the prior select menu in the BIOS.Yes, It is an emergency issue I had to face.

The chassises we sold were designed by Intel Corp. We do not know how to dare with such a strange matter. So we had to change this board and took it back to our lab. I had done many times test in checking the existing of ethernet devices by building a test environment including one cpu,one memory and one power supply. The factor is the ethernet devices are really lost, we could not find them again.

We send this board from Hainan customer to Inter TME who is the Alief own. Mr Yue is a kind man with good patience. He did the FA, and told that two capacitances between the Air Conductor and board had been destoried. This issus had been reported from Eurpean customer two months ago.

When we are discussing the reason which cause this matter, another board in Hainan was down for the seem phenomena: Ethernet devices were lost. Mr Yue said, there were two reversion named 601 and 602 made in Intel Korean factory, and these board did not pass the test which could halted the operating system in two weeks. The engineer renewed his board by adding some components and update 601 and 602 to 603. The latest version of Alief is 703. The board we got is 601 update to 603 with a green dot signed on the PBA label.

The issus is caused by Airconductor of SC5300BRP, not Alief Board. Intel has commited it is their design bug.They plan to add a “L” palstic on the board to provent they were destoried by the SC’S airconductor. This “L” platic are still testing in their factory and not released to end users. We had to use a small sponge instead of the palstic.

Mandriva’s interface looks more simply than SuSE and Red Hat Linux. When the first reboot after installation completed, the background is red and there is no iron.

I love Mandriva.It has better font character than SuSE, beautiful looking and charmful.During the first installation, I do not configure the right display parameter, so when the system restart, it entried Text mode directly and showed that it could not found the right screen server.
The xorg files are invalidate. I tested the configuration for the second time with choosing “Inter 910” X server. Everything is ok. It’s my Mandriva!

It’s my first article in 2006.

The MSN space has became my private area, in which I could write my working experience, thinking of life. Since June 2005, the blog launched. In those days, I had a project building in Orace RAC in Intel ISC, through I did not go to Guangzhou by myself.

James told me to develop my road in Linux Technology. He is a powerful leader, wise man, and such a good director and kind friend. I do feel a litter disappoint when he went back to Beijin because I think I could learn more from him.

In December 12th, I decided to separate with Lily. She lies, I do not believe her any longer. What she had done before also hurt me deeply. She is always a liar. Robin, my best friend says,”Separate is right, I think you should have done this three years ago.”

How many roads must a man walk down, before you call him a man?

Maybe the answer is blowing in the wind.

Mandriva is the next target operating system to be installed in my server station.

Thanks for the following guys and girls who help me in 2005, you are all my good friends: Chris Cao, Alan Tang, Xeon Xiong, Zephry Feng, James Guan, Dehu Jin, Chiristine Xiao, Lihua Li,Dong Ye, Amani Zhang, Honefei,Gao, Julian Yan, Zleopard Zhao, Sydeny Liu, Shu Bi, and my best friend Robin.

Sometimes, we need to run the processes in the background.The following four command are useful : crontab, at, & and nohup.

crontab syntax:

# crontab [-u user] -e -l -r 

-u : user
-e : edit or modify the crontab file
-l : list the crontab file contents.
-r : delete the crontab file crontab is schedule periodic background work,and it maintain the crontab files for individual users.

Every user could has his own crontab file, but in most case, system administrator forbids this operation by modifying ‘cron.deny’ and ‘cron.allow’ file, and the sa will keep only one crontab file for all users.

In the crontab tables,the meaning of every column are showed here:

The 1st column : miniute (1-59)
The 2nd column: hour (1-23,and 0 indicates middle night )
The 3rd column: date (1-31)
The 4th column: month (1-12)
The 5th column: week (0-6, o is sunday)
The 6th column: command will be executed (Note,absolute directory must be added)
eg:

10 9 24 11 4 /sbin/init 6 

This string means the system will reboot at November(11) 24,9:10,Thursday.

A useful command:

# ps -x
# ps -fe

-x : processes w/o controlling ttys.
-e : all processes
-f : output format

when I issued ‘ps -x’ command, I found there was such a line showing in the screen:

...... 
5942 ? S 0:07 kmail -caption KMail -icon kmail -miniicon kmail 
...... 

So,I wanted to make the kmail processes startup automatic when the user logs in. I modified the crontab files by adding the following lines:

.... 
32 11 24 11 4 /opt/kde3/bin/kmail 
.... 

And waited for the action happening,but at the 11:10, SuSE told me that I had gotten a mail in the /var/spool/mail/root which said ‘ERROR:kUnique Application,Can’t determing DISPLAY Aborting’. Oh, what’s the matter?

I added an other line indicating the display parameter before the kmail command in crontab file:

10 11 24 11 4 export DISPLAY=0:0 ; /opt/kde3/bin/kmail 

But I still received an error report in /var/spool/mail/root:

----------/var/spool/mail/root--------------- 

From root@linux.site  Thu Nov 24 11:32:21 2005
Return-Path: <root@linux.site>
X-Original-To: root
Delivered-To: root@linux.site
Received: by linux.site (Postfix, from userid 0)
 id C017E101213; Thu, 24 Nov 2005 11:32:21 +0800 (CST)

From: root@linux.site (Cron Daemon)
To: root@linux.site
Subject: Cron <root@linux> export DISPLAY=0:0 ; /opt/kde3/bin/kmail 

X-Cron-Env: <SHELL=/bin/sh>
X-Cron-Env: <HOME=/root>
X-Cron-Env: <PATH=/usr/bin:/bin>
X-Cron-Env: <LOGNAME=root>

Message-Id: <20051124033221.C017E101213@linux.site>
Date: Thu, 24 Nov 2005 11:32:21 +0800 (CST)

_X11TransSocketINETConnect() can't get address for 0:6000: 
Name or service not known
kded: cannot connect to X server 0:0
DCOP aborting call from 'anonymous-5910' to 'kded'
kded: ERROR: Communication problem with kded, it probably crashed.

_X11TransSocketINETConnect() can't get address for 0:6000: 
Name or service not known
kdeinit: Can't connect to the X Server.
kdeinit: Might not terminate at end of session.

_X11TransSocketINETConnect() can't get address for 0:6000: 
Name or service not known
kmail: cannot connect to X server 0:0
DCOP aborting call from 'anonymous-5901' to 'kmail'

ERROR: Communication problem with kmail, it probably crashed.
Mutex destroy failure: Device or resource busy
sh: line 1: iceauth: command not found

The test failed. I’ll try to resolve this problem later.Maybe using pipe is a good idea.Waiting…

at syntax: at [-f script] [-m -l -r] [time] [date] 

-f script : Shell script or command
-m : mail the report to user
-l : list the quote contains waiting jobs
-r : cancel the job by using its job-ID
time : H,HH,HHMM,HH:MM,H:M
date : today,tomorrow

at has two mode: command line and prompt mode.
Command line mode,for example:

$ at 3.00 pm tomorrow -f /apps/bin/db-table.sh 
Prompt mode: 
$ at 14:08 
at> find / -name 'adobe' > report.txt 
at> [EOT] 

[EOT],NOT IS EOF,means “CTRL+D” to save and quit the at prompt mode. Note,once the job was submitted, at will store the running environment including path.but Using crontab command,we must identify the absolute directory.

& character : command &

& is used to make the job running in the background.These jobs may be find,print,soft,Shell Script and other high-costing issues.The interactive of user is forbidden,or it will confuse the system to make it waiting forever. eg:

 $ find -name 'adobe' & 
[1] 6531 linux 
$ ps -e 
PID      TTY       TIME          CMD 
... 
6510     tty2     00:00:00       bash 
6532     tty2     00:00:00       ps 
[1]+ Done ...... find -name 'adobe'