Installing packages on linux from command line
what program does the kernel run upon boot up?
/sbin/init - starts up all other basic programs that the computer needs to run
where are most log files saved?
/var/log
what is inits pid?
1
5 steps of typical software installation task
1. a command is issued to install program 2. the software locates dependencies of the specified program 3. the user issues a final approval for software installation 4. the software downloads all of the necessary packages 5. the software installs all the packages
system messaging
a technique wherein a log daemon accepts messages from other processes
apt is short hand for?
advance packaging tool
memory leak
application or program that is borrowing and not returning memory to it. could be bad programming or other causes
debian based package manager?
apt
software repositories are?
area where tools can be downloaded automatically as packages and then installed
what information does package manager contain about packages?
names and version numbers, as well as locations of all installed packages
common log files
boot.log cups/ gdm/ messages or syslog secure Xorg.0.log many more
can a debian package be installed on a rpm manager?
no, each package must be native to your system
PPID
parent process ID
PID
process ID
children
program launched by other programs
daemon
program running in background
parent
program that launches other programs
how do you exit the top program?
q or ^c (ctrl c)
sudo apt remove <software>
removes particular program that is installed on the computer
sudo apt autoremove
removes programs that your computer thinks aren't necessary
swap
reveals how much swap space is being used - disk space that's set aside as an adjunct to memory
mem line
reveals total ram statistics
apt search <word>
searches for particular program that you would like to install
log file
serves as records or notes
rpm based package manager?
yum or dnf
top
very much like taskmanager in windows - interactive version of ps
6 characteristics of packages
1. each package is a single file 2. packages rely on other programs to do the work of installing the software 3.packages contain dependency information 4. packages contain version information 5. packages contain architecture information (identifies cpu or processor type) 6. binary packages are built from source packages
kernel ring buffer messages are invaluable in what?
diagnosing hardware and driver problems
ps
displays all processes currently being ran - snapshot of current processes
kernel ring buffer command
dmesg
a child can not be a parent - t or f
false all programs can be parents
Log files are permanent t or f
false they are frequently rotated to stop computer from filling up with log files
package management is the same for each distro t - f
false, package management varies between distros
what is tops main usage?
figure out what is consuming the most cpu time
what does dmesg do?
gives all info about kernel ring buffer
apt info <word>
gives info about the particular program
klog/klogd
handles logging messages from the kernel separately from ordinary programs
sudo apt install <software>
installs particular program you want to install
kernel ring buffer is what?
log file for kernel itself
pressing m within top does what?
sorts by memory being used instead of cpu usage
syslog or syslogd
syslog daemon fills with system logs
free
tells you how much memory is being used
modern distros have network enabled tools that allow you to automatically download dependencies - t or f?
true, in the past you would have to hunt down and install packages manually and hope that you had them all
sudo <apt or dnf or yum> update
updates the current list of installed programs
sudo <apt or dnf or yum> upgrade
upgrades your current computer to the update list