Some Ubuntu troubleshoot

How to install/confige nvidia driver?

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  Solution A. install driver from nvidia homepage directly (highly not recommended!!!)

    1. download elf from nvidia homepage

    2. possiblely need to shutdown  "lightdm/kdm/gdm"

      > sudo service lightdm stop

    3. press Ctrl-Alt-F1 to attach to tty1

    4. If you explode, try fix with blacklist of modules(drivers) under /etc/modprobe.d

  Solution B.

    1. get driver

       i. from "Additional drivers"

       ii. from "sudo apt-get install nvidia-current-update"

    2. config your "lightdm/kdm/gdm"

      > sudo nvidia-xconfig

   http://askubuntu.com/questions/306090/12-04-failed-to-load-module-nvidia-module-does-not-exist-0

Much better: http://www.dedoimedo.com/computers/ubuntu-quetzal-nvidia.html

Login with ssh public key
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Scenario: your local ssh want to login into remote ssh server as user "inker"
1. push your local public key to remote inker's home directory
2. make file "~/.ssh/authorized_keys" on server as user "inker" if the file not exist
3. cat "your local public key" >> ~/.ssh/authorized_keys