91d437f0fb56cfb5b64de81b60bd6738

I was asked by my manager & team to compose a tiny test of Linux command line for new hire @ development. Share it here:

1. ssh -X: what does “-X” mean?
   Answer: enable X-window forward over SSH on port 22
2. What is “authorized_keys2“? What does 2 mean”? Where is it supposed to stay?
   Answer: enable passwordless login in SSH2 protocol in ~/.ssh/
3. What is “createrepo Server”
   Answer: to create a YUM repository in directory of “Server”
4. How can I know detailed launched kernel in Unix?
   Answer: uname -a
5. How can I know whether KVM package installed in Redhat and Ubuntu?
   Answer: rpm -qa | grep -i kvm and dpkg -l | grep -i kvm
6. What does “lvcreate -L5G -n redhat VolGroup00” mean?
   Answer: to create/ new a logical volume (lv) in 5G size, named “redhat”, on top of volume group (vg) named “VolGroup00″.
7. What does “set -o vi” mean? Where could it be run?
   Answer: to set vi editing mode in shell. Either in a BaSH shell or put it in bottom of /etc/bashrc for login shell
8. What difference between “rpm -Uvh PACKAGE_NAME” and “yum install PACKAGE_NAME”
   Answer: rpm one = install specific & particular rpm package named PACKAGE_NAME. yum install = install rpm package named PACAGE_NAME, and with associating dependent package(s) from repo.
9. What is “yum install kvm libvirt virt-manager“? What purpose of such command?
   Answer: to install kvm libvirt virt-manager packages. To install/ enable Kernel- based Virtual Machine in Linux
10. What does “gpg –output doc.gpg –encrypt –recipient blake@domain.org doc” mean?
    Answer: to encrypt “doc” file, by using public key of blake@domain.org, then output result into doc.gpg
11. What is “iptables -L -n -v?
    Answer: to list (-L) firewall rules in selected chaim in iptables. -n = in numberic, -v = verbose
12. How can I check default installed java info?
    Answer: java -fullversion
13. How can I know default java home setting?
    Answer: echo $JAVA_HOME
14. What is result of “lslpp -l bos.rte.libc” on AIX?
    Answer: rte = runtime environment. To tell runtime libc version, aka AIX version.
15. What does “chkconfig xinetd off” mean?
    Answer: to disable xinetd daemon from all runlevels.
16. What is “sysctl -w net.ipv4.ip_forward =’1′“?
    Answer: turn on IP_forward in system control. Take effective immediately without reboot.
17. What is “tcpdump -i eth1 ‘proto UDP and (port not 53)’“?
    Answer: to capture all UDP traffic packet, but besides on port 53, in tcpdump.
18. Describe the following block in httpd.conf?
    <virtualhost *:80>
    ServerName smallblue4.watson.ibm.com
    Redirect / http://spirit125.watson.ibm.com/smallblue
    </virtualhost>
    Answer: redirect all http traffic hitting smallblue4.watson.ibm.com over port 80 to spirit123.watson.ibm.com/smallblue
19. What is “echo 0 > /selinux/enforce“?
    Answer: temporarily disable Security Enhancement Linux
20. What is “/etc/init.d/iptables status“?
    Answer: to check iptables (firewall) running status.

One of my colleagues was impressed by the 3D desktop, driven by CompizConfig on my Ubuntu 10.04.

He then asked me how to install one on his ThinkPad T43 machine. Giving the steps:

1. Find a 2G USB key. Click Download @ http://www.ubuntu.com/desktop
2. You’d be given an ISO file. Then follow the step 2 & select “Create a USB stick” @ http://www.ubuntu.com/desktop/get-ubuntu/download
   
3. Restart your Windows then boot from USB key
4. From the same page you can either run Ubuntu from USB to start the installation
   

91d437f0fb56cfb5b64de81b60bd6738 ->

$ echo “a man on linux” | openssl dgst

or

$ echo “a man on linux” | md5sum

I’m using Linux as my primary desktop. And in the contrast, currently Nokia doesn’t supply application(s) to support Linux. I have to find a way to get rid of USB cable…

The first application I need is SIC!FTP. With this application, all files (in batch) could be transferred between my phone and Linux machine(s) through wifi, even without SIM card.

Let’s see what else are installed in which you might get interested too. I walk you through one by one

LotusTraveler: Light Lotus Notes client on Symbian platform. Needs a gateway to get authenticated to office Notes mail server.

ProblemReport: with LotusTraveler. Have never used that once. Hopefully will not.

MobClient: Lotus Mobility Client. A VPN client on symbian

Putty: This is great tool that gives a native SHELL to access and control any Unix/ Linux machine.

GoogleMap: v3.0 with Latitude = maps + location of your friend

SpotOn: keeps backlid and/ or camera light on.

Mobbler: This is a great Web2.0 online music radio that allows you tag your loved tracks (banable too) and bridges you into community with Common Interest.

fring: You know this one

5ud0ku: Sudoku. There are a lot of similar. This is the best. Try it while waiting @ airport.

Sametime: Lotus messenger

Gmail: Application on Symbiam, which contains mail thread function.

Opera Mini: the most popular browser on mobile. Looking forward to Firefox Fennec

WorldMate: free from Nokia to assist you during travel in diff timezone, weather and currency exchange. Heard it eat traffic a lot.

SIC!FTP: If you’re a Linux guru, you’d love this to turn your phone to a real computer.

Gizmo5 & Skype (beta) as they are.

Screenshot: is a tool that I used to capture screens.