Problems met when installing ubuntu with RAID1

0. "BOOTMGR is missing" when installing from usb
A: Format the drive as FAT (not FAT32)


1. Unable to install GRUB in /dev/sdb

A: From the link http://askubuntu.com/questions/43036/how-do-i-install-grub-on-a-raid-system-installation

Many of the answers here are just plain incorrect, telling you to disable BIOS RAID! The correct solution is atthis blog entry. I'll summarize it below.

At the stage of the install where it is attempting to install GRUB it will detect as

/dev/mapper

This is incomplete! That's why the GRUB install fails.

You need the actual name of the RAID array to install to. So during that step, pressctrl+alt+F2 to drop to a busybox terminal, then enter

ls -l /dev/mapper

Pick out the name of your array from the list shown, then press ctrl+alt+F1 to switch back to the install (you can switch back and forth as much as you like with no problems) and enter it in the field as

/dev/mapper/{your array name}

then GRUB installs perfectly and you're ready to go, with a proper BIOS RAID array intact.

It works in my case...

2. What is the default root password of ubuntu?

A: just sudo -i to enter the root mode. 

3. How to enter graphical mode from command line?

A: Plz refer to  http://www.linuxquestions.org/questions/ubuntu-63/%5Bstartx-problem%5D-startx-goes-to-black-grey-screen-and-comes-back-to-command-prompt-853802/

sudo apt-get install xinit

sudo apt-get install ubuntu-desktop  (it takes a long long time...)

Set up a svn server on linux quickly

Here is a quick guide for setting up a basic svn server on a linux platform. If you are looking for a detailed configuration, please refer to the manual of svn.

1. yum -y intall subversion  #install svn
2. svnadmin create /xx/svn_repository/plancky_code   #create a repository
3. cd /xx/svn_reposity/plancky_code and then modify server.conf, passwd   # add user and password
• vim server.conf and uncomment "password-db = passwd"
• vim passwd and add an item "username=password"
4. svnserve -d -r /xx/svn_repository/plancky_code   # start svn server
5. svn import /xx/plancky svn://localhost/plancky_code -m initial import --username username --password password  #import plancky to repository
6. svn co svn://localhost/plancky_code --username username --password password  #check out code from repository

• ERROR: If meeting Error"SVN: could not use external editor to fetch log message", we need to add a SVN_EDITOR to bash configuration
•       vim ~/.bash_profile
•       export SVN_EDITOR="/usr/bin/vim"
•       reopen the terminal to load the bash configuration

Check open files setting of Fedora 13

1. List all the settings
ulimit -a

2. change the limit of maximum open files setting
ulimit -n [number]

The smaller open files number will cause a JAVA procedure throw exception like

 Java.net.SocketException: Too Many Open Files?

Checkout the current open files number per process in fedora

lsof -p [pid]