Linux Command Test to New Hire @ Company :)
I was asked by my manager & team to compose a tiny test of Linux command line for new hire @ development. Share it here:
- ssh -X: what does “-X” mean?
Answer: enable X-window forward over SSH on port 22 - What is “authorized_keys2“? What does 2 mean”? Where is it supposed to stay?
Answer: enable passwordless login in SSH2 protocol in ~/.ssh/ - What is “createrepo Server”
Answer: to create a YUM repository in directory of “Server” - How can I know detailed launched kernel in Unix?
Answer: uname -a - How can I know whether KVM package installed in Redhat and Ubuntu?
Answer: rpm -qa | grep -i kvm and dpkg -l | grep -i kvm - 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″. - 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 - 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. - 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 - 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 - What is “iptables -L -n -v?
Answer: to list (-L) firewall rules in selected chaim in iptables. -n = in numberic, -v = verbose - How can I check default installed java info?
Answer: java -fullversion - How can I know default java home setting?
Answer: echo $JAVA_HOME - What is result of “lslpp -l bos.rte.libc” on AIX?
Answer: rte = runtime environment. To tell runtime libc version, aka AIX version. - What does “chkconfig xinetd off” mean?
Answer: to disable xinetd daemon from all runlevels. - What is “sysctl -w net.ipv4.ip_forward =’1′“?
Answer: turn on IP_forward in system control. Take effective immediately without reboot. - 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. - 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 - What is “echo 0 > /selinux/enforce“?
Answer: temporarily disable Security Enhancement Linux - What is “/etc/init.d/iptables status“?
Answer: to check iptables (firewall) running status.
Permalink Comments off













