Red Hat Training: Day 3

Yum


# yum list (get the list of .rpm, which stands for RPM Package Manager)
# yum search kernel (kernel is the name of the package)
# yum install kernel
# yum update kernel
# yum remove kernel

Network


# ip addr show eth0 (eth0 is the name of the network)
# more /etc/sysconfig/network-scripts/ifcfg-eth0
# service network restart
# system-config-network
# ip route
# host visualgui.com
# dig visualgui.com

Users and Groups


# useradd donny
# passwd donny
# vipw (let’s one user edit at the same time)

Manage Files


# echo $PATH
# pwd (current path)
# ls /home/{dir1,dir2} (show more two directories)
# ln file1 file2 (link file 1 to file 2)
# ln -s file1 file2 (symbolic link)
# su – username (change user)
# cp -av /dir/to/copy /dir/destination

Permission


r (view content)
w (change the content)
x (requires r to execute the content)

rw-rw-rw-
rw-r–r–
umask 002

u+s (suid=4: file executes as the user that owns the file, not the user that ran the file
g+s (sgid=2: file executes as the group that owns the file
o+t (sticky=1: no effect)

Summary: The best day so far of the training. Picked up many useful information. Hope the next two days will be even better.