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Cheatsheet Linux General

cat

display the content of a file

show contents of group.ini:

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cat group.ini

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<services>
        <cisco_vxme_client>
                enabled=<true>
        </cisco_vxme_client>
        <ica_client>
                enabled=<true>
...

cd

change folder

change folder to /wfs/:

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cd /wfs/

chmod

change file attributes

make new.sh executable:

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chmod +x new.sh

comm

compare two sorted files line by line

Simple method to determine command line to run (such as IGEL setup or IGEL About):

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# what processes are running BEFORE item is run?
ps -ef | sort > /tmp/ps1.txt

# what processes are running AFTER item is run?
ps -ef | sort > /tmp/ps2.txt

# what are the new processes?
# comm only showing processes in /tmp/ps2.txt
comm -1 -3 /tmp/ps1.txt /tmp/ps2.txt

Start IGEL setup: /bin/bash /config/bin/start_setup

Start IGEL About: applauncher -style gtk2 --aboutOnly

compgen

list all the linux commands (including bash shell aliases and functions)

list all igel and remotemanager related commands:

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compgen -c | egrep "igel|_rm" | sort | more

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get_rmdirlist
get_rmsettings
get_rmsettings_boot
...
igel_showsplash
igel-shutdown-debug
igel-shutdown-inhibitor
--More--

conky

system monitor

KB: Conky

Conky Reference with Examples

NOTE: To remove black rectangle on OS 12, enable the registry key windowmanager.wm0.variables.usecompositing in the registry part of your profile, and add a custom setting config name = own_window_argb_value and config value = 0 to Conky profile.

cp

copy files and folders

create backup of setup.ini:

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cp setup.ini setup.ini.bck

date

date tool

show date:

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date

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Mi 19. Mai 19:26:59 CEST 2020

dig

DNS lookup utility

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#!/bin/bash

MACHINE="goober.mydomainname.com"

# use the dig command to resolve an IP only on client network
if [ "$(dig $MACHINE +short)" ]; then
  echo "On the client network"
  echo "do some on network work now"
else
  echo "Not on client network"
  echo "do some off network work now"
fi

echo

output strings

outputs "hello world" to console:

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echo "hello world"

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hello world

find

search for all files in the /services folder that have snmp in the name

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find /services -type f -name "*snmp*" | less

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/services/cups/lib/cups/backend/snmp
/services/cups/share/cups/doc-root/help/man-cups-snmp.html
/services/cups/share/cups/snmp.conf.default

copy all files in /userhome that end in .log to /tmp/foo folder

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mkdir /tmp/foo; find /userhome -name "*.log" | xargs cp -t /tmp/foo

grep

search for regular expression

search for configured UMS server name:

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more /wfs/setup.ini | grep "ip="

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ip=<igelrmserver.int.acme.org>

kill

kill a running task by process id

kill process with PID 48:

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kill 48

killall

kill a running task by name

kill process with name pnlogin:

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killall pnlogin 2>/dev/null

less

less is more and allows backward movement (hit "b" key) in the file, as well as forward movement (hit "f" key), search for string (hit "/" key and enter string to search for), or to quit (hit "q" key)

show contents of group.ini, hit key "f" to go forward, hit key "b" to go backward, hit key "/" and the text to search for:

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less /wfs/group.ini

ls

show directory content

long list current directory:

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ls -l

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total 96
drwxr-xr-x  3 root root     60 Mai 20 13:49 apparmor
drwxr-xr-x  2 root root     40 Mai 20 13:49 asset.events
-rw-r--r--  1 root root   2765 Mai 20 13:50 asset.ini
drwxr-xr-x  2 root root    100 Mai 20 13:50 ca-certs
drwxr-xr-x  2 root root     60 Mai 20 13:49 chrony
...
-rw-------  1 root root    106 Mai 20 13:50 systemkey
-rw-r--r--  1 root root     49 Mai 20 13:50 systemmd5
-rw-------  1 root root     32 Mai 20 13:49 tckey
-rw-------  1 root root    214 Mai 20 13:49 updateconf.ini
drwxr-xr-x 14 user users   440 Mai 20 13:50 user
drwxr-xr-x  2 root root     40 Mai 20 13:49 zoneinfo

lshw

list hardware

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lshw -short

mkdir

create a folder

create folder with name newdir:

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mkdir newdir

create folder dir3 and make parent directories dir2 and dir1 if they do not exist

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mkdir -p /tmp/dir1/dir2/dir3

more

display the content of a file page by page

show contents of group.ini, hit space to continue to next page:

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more group.ini

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<services>
        <cisco_vxme_client>
                enabled=<true>
        </cisco_vxme_client>
        <ica_client>
                enabled=<true>
...

mount

mount a partition

mount license folder writeable:

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mount -o remount,rw /license

openssl

OpenSSL command line tool

Find end date on certificates

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cd /etc; find . -type f \( -name "*.cer" -o -name "*.crt" -o -name "*.pem" \) -exec echo "FILE NAME: ==> " {} \; -exec openssl x509 -enddate -noout -in {} \;

ps

show running tasks

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ps -aef

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UID        PID  PPID  C STIME TTY          TIME CMD
root         1     0  0 13:49 ?        00:00:03 /sbin/init 3
root         2     0  0 13:49 ?        00:00:00 [kthreadd]
root         3     2  0 13:49 ?        00:00:00 [rcu_gp]
root         4     2  0 13:49 ?        00:00:00 [rcu_par_gp]
root         6     2  0 13:49 ?        00:00:00 [kworker/0:0H-kb]
root         8     2  0 13:49 ?        00:00:00 [mm_percpu_wq]
root         9     2  0 13:49 ?        00:00:00 [ksoftirqd/0]
root        10     2  0 13:49 ?        00:00:00 [rcu_sched]
root        11     2  0 13:49 ?        00:00:00 [rcu_bh]
...

pwd

print working directory

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pwd

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/root

rm

delete a file

delete file with name new.sh:

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rm new.sh

rmdir

delete a folder

delete folder with name newdir:

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rmdir newdir

sleep

wait

wait for 5 seconds:

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sleep 5

su

change to root

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su

systemctl

service handler

restart network:

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systemctl restart network-manager

top

task monitor

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top

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top - 14:15:59 up 26 min,  2 users,  load average: 0,05, 0,01, 0,01
Tasks: 236 total,   1 running, 168 sleeping,   0 stopped,   0 zombie
%Cpu(s):  0,1 us,  0,1 sy,  0,0 ni, 99,8 id,  0,0 wa,  0,0 hi,  0,0 si,  0,0 st
KiB Mem :  1891000 total,   351040 free,   481452 used,  1058508 buff/cache
KiB Swap:  1134592 total,  1134592 free,        0 used.  1183616 avail Mem

  PID USER      PR  NI    VIRT    RES    SHR S  %CPU %MEM     TIME+ COMMAND
18620 root      20   0   79776   4276   3520 R   0,3  0,2   0:00.02 top
    1 root      20   0  205624   9980   5812 S   0,0  0,5   0:03.88 systemd
    2 root      20   0       0      0      0 S   0,0  0,0   0:00.00 kthreadd
    3 root       0 -20       0      0      0 I   0,0  0,0   0:00.00 rcu_gp
    4 root       0 -20       0      0      0 I   0,0  0,0   0:00.00 rcu_par
...

touch

create a file

create file with name new.sh:

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touch new.sh

tr

translates, deletes, and squeezes characters

Print $PATH directories on a separate line

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echo $PATH | tr  ':' '\n'

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/bin
/sbin
/usr/bin
/usr/sbin

Remove the repeated space characters

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ps -ef | tr -s ' ' | grep terminal

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user 23850 23849 0 10:30 ? 00:00:00 /usr/bin/xfce4-terminal -T Local Terminal -e check_passwd --disable-server --geometry 90x38
user 23915 23860 0 10:44 pts/0 00:00:00 grep --color=auto terminal

Remove all non-numeric characters

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echo "IGEL support for Priority or Plus support phone number for US and Canada is 415-813-3933" | tr -cd [:digit:]


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4158133933
Print strings with ; separator on separate lines

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echo "this; is; a; test" | tr -d ' ' | tr ';' '\n'

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this
is
a
test

uname

show linux details

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uname

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Linux

user_shutdown

shutdown the system

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user_shutdown

user_reboot

reboot the system

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user_reboot

vi

texteditor

open setup.ini in vi:

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vi setup.ini

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<system>
        <remotemanager>
                <server0>
                        ip=<igelrmserver.int.acme.org>
                </server0>
        </remotemanager>
        <icg>
                <server0>
                        host=<icg.acme.org>
                        uuid=<d8d43ff7a4274b8f96fb6ec96c4948>
....
        <drivers>
                currentdriver=<intel>
                currentconnectors=<lvds1,Seiko Epson Corporation,,1366,768,1366,768,0,0,,;>
        </drivers>
</x>

watch

repeat periodic a command

probe tcp port 8443 on igelrmserver every 2 seconds:

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watch probeport igelrmserver 8443

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Every 2,0s: probeport igelrmserver 8443                                                                                                                       ITCA44CC8C90000: Wed May 20 14:24:08 2020

Connection successful

wget

non-interactive network downloader

  • Obtain internet IP address for device
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wget -qO- http://ipv4.icanhazip.com; echo
  • Download IGEL OS 12.3.2 OSC installer
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wget https://az743625.vo.msecnd.net/files/IGEL_OS_12/OSC/osc-12.3.2.zip
  • Download a file from UMS
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wget https://<server:port>/ums_filetransfer/file_name --no-check-certificate --user=username --password=password

which

locate command

locate command nmcli:

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which nmcli

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/usr/bin/nmcli
sleep 1; xset dpms force on;  # dpms screen ON after a delay of one second.

wmctrl

List windows managed by the window manager

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wmctrl -l

Close VMware window

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wmctrl -c VMware

Execute the VMware Horizon client as maximized or full screen using wmctrl command

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#!/bin/bash
/config/sessions/vdm_client0 &
sleep 2 &&

#uncomment for maximized
wmctrl -x -r vmware-view -b add,maximized_vert,maximized_horz
#uncomment for fullscreen
#wmctrl -x -r vmware-view -b add,fullscreen

Bring IGEL UMS Console to the foreground

  • List the windows
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wmctrl -l

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0x02000003 -1 ITC08002792DECB xfce4-panel
0x02200069 -1 ITC08002792DECB Desktop
0x03200003  0 ITC08002792DECB X11
0x03400401  0       igelums12 IGEL Universal Management Suite 12
0x03800003  0 ITC08002792DECB Local Terminal
  • Raise UMS Console to the foreground
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wmctrl -i -a $(wmctrl -l | grep igelums | cut -f 1)

xinput

utility to configure and test X input devices

list all input devices:

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xinput --list

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⎡ Virtual core pointer                      id=2    [master pointer  (3)]
⎜   ↳ Virtual core XTEST pointer                id=4    [slave  pointer  (2)]
⎜   ↳ 3830303142534F54:00 06CB:CE46 Mouse       id=11   [slave  pointer  (2)]
⎜   ↳ Logitech USB-PS/2 Optical Mouse           id=9    [slave  pointer  (2)]
⎜   ↳ 3830303142534F54:00 06CB:CE46 Touchpad    id=12   [slave  pointer  (2)]
⎣ Virtual core keyboard                     id=3    [master keyboard (2)]
    ↳ Virtual core XTEST keyboard               id=5    [slave  keyboard (3)]
    ↳ Toshiba input device                      id=14   [slave  keyboard (3)]
    ↳ Video Bus                                 id=6    [slave  keyboard (3)]
    ↳ Power Button                              id=7    [slave  keyboard (3)]
    ↳ Sleep Button                              id=8    [slave  keyboard (3)]
    ↳ AT Translated Set 2 keyboard              id=13   [slave  keyboard (3)]
    ↳ Web Camera - HD: Web Camera - H           id=10   [slave  keyboard (3)]

disable touchpad:

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xinput set-prop "3830303142534F54:00 06CB:CE46 Touchpad" "Device Enabled" 0

xset

user preference utility for X

Screen Blanking

testing dpms signal for monitor to turn off, waiting 15 seconds, then signal monitor to turn on

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sleep 1; xset dpms force off; sleep 15; xset dpms force on;
commands to trigger the various states

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sleep 1; xset s activate;  # will blank the screen (or activate the screensaver program, if you're using one) after a delay of one second
sleep 1; xset dpms force off;  # dpms turn the screen OFF after a delay of one second.
sleep 1; xset dpms force standby;  # dpms screen standby after a delay of one second.
sleep 1; xset dpms force suspend;  # dpms screen suspend after a delay of one second.

zenity

Display dialog window, and return (either in the return code, or on standard output) the users input

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#!/bin/bash
Zenity_String=$(zenity --forms --title="Create user" --text="Add new user" \
  --add-entry="First Name" \
  --add-entry="Last Name" \
  --add-entry="Username" \
  --add-password="Password" \
  --add-password="Confirm Password" \
  --add-calendar="Expires")

First_Name=$(echo $Zenity_String | cut -d "|" -f 1)
Last_Name=$(echo $Zenity_String | cut -d "|" -f 2)

echo "Zenity String: " $Zenity_String
echo "First Name: " $First_Name
echo "Last Name: " $Last_Name

Suspend system dialog window

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#!/bin/bash
(
echo "10" ; sleep 1
echo "# Suspending countdown" ; sleep 1
echo "20" ; sleep 1
echo "# Suspending countdown" ; sleep 1
echo "50" ; sleep 1
echo "# Suspending countdown" ; sleep 1
echo "75" ; sleep 1
echo "# Suspending countdown" ; sleep 1
echo "100" ; sleep 1
auto_suspend
) |
zenity --progress \
  --title="Suspending system" \
  --text="Suspending system..." \
  --percentage=0

if [ "$?" = -1 ] ; then
  zenity --error \
  --text="Suspending canceled."
fi