vi /etc/networking/interfaces auto eth0 iface eth0 inet static address 192.168.0.99 netmask 255.255.255.0 gateway 192.168.0.1 sudo systemctl disable dhcpcd sudo systemctl enable networking reboot
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Autor: untony
RetroPi + CamPi
Recieved 2 additional Raspis and couldnt’stop setting them up unfortunately the display ordered was broken so i didnt build the mobile RetroPi. So I tried it with my cheap china beamer:
Longrunner Cam with Raspberry and self build Lego Case.
Unfortunately broken display (Raspi HD TFT Hat 800×480).
But a 10″ touch screen and case arrived
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NetPi Setup
+ Raspberry Pi 3 B+
+ Anker PowerBar (10000 mAh)
Installed NetPi Image from: https://drive.google.com/drive/folders/1pCzC8NRPJU0gfBHewlNSo_Z0O3xk7fbY
see also:
http://www.blamethenetwork.com/netpiplus/
Install additional Kali-Tools
apt-get install git # git clone https://github.com/LionSec/katoolin.git && sudo cp katoolin/katoolin.py /usr/bin/katoolin chmod +x /usr/bin/katoolin katoolin
establish remote ssh-connection via ssh reverse tunnel (provides ssh-connection to rasp in a network via a server/device with a public ip)
on the raspberry:
ssh -R 2222:localhost:22 loginOfServerIP@ServerIPon server side to connect back to raspberry:
ssh -p 2222 loginOfComputerWithoutPublicIP@localhost
verify usage of autossh if regularely needed
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MySQL server has gone away
mysql::db do failed: MySQL server has gone away at ./inclibdb.pm line 1848
Solved by
set a higher value for wait_timeout and connect_timeout in my.cnf
from the MySQL Documentation
- wait_timeout : The number of seconds the server waits for activity on a noninteractive connection before closing it.
- connect_timeout : The number of seconds that the mysqld server waits for a connect packet before responding with Bad handshake
EXAMPLES
- If wait_timeout is 1800 (30 Minutes), the DB Connection will close in 30 minutes if the connection is idle (indicated by
Sleepin the command column of the processlist). - If connect_timeout is 10, then mysqld will reject you if you cannot login (authenticate) in 10 seconds.
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Kernel Panic after upgrade
Kernel Panic after yum upgrade to kernel 3.10.0-957.1.3.el7.x86_64 ona Centos 7 VM:
– booted old kernel
– no initramfs-3.10.0-957.1.3.el7.x86_64.img in /boot
Solved by
– yum remove kernel-3.10.0-957.1.3.el7.x86_64
– verify uninstallation
rpm -qa | grep kernel | sort
– reinstall
yum install kernel-3.10.0-957.1.3.el7.x86_64
– verify again, check initramfs creation in /boot
rpm -qa | grep kernel | sort ls -la /boot/initram
reboot into new kernel
see also: https://ma.ttias.be/reinstall-the-linux-kernel-on-centos-or-rhel/
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sendmail tings
Send mail via sendmail
vi /tmp/email.txt
Insert
Subject: Terminal Email Send
Email Content line 1
Email Content line 2
(ESC)wq(ENTER)
sendmail user@example.com < /tmp/email.txt
Quick and dirty, with subject only:
mail -s "Test Subject" user@example.com < /dev/null
Faking Mails with cutomized sender:
mail -s "Everything possible" -aFrom:bill.gargantur@iliketobeanemailfaker.com recipient@maildomain.com < /dev/null
*Will be delivered into spamfolder or not delivered cause SPF checks that mailsender is not authorized sender of the maildomain –> only if accurate spamsolution/SPF is implemented on recipient side
Install/Config sendmail
for just relay edit /etc/mail/sendmail.cf and add:
"Smart" relay host (may be null)
DSrelay.example.com
or if ip based:
"Smart" relay host (may be null)
DS[10.10.10.10]
of course relay host must permit this.
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Process check script for linux
If you ever wanted an automation when a process is not running it is just a small script helping to achieve this:
check_process.sh (dont forget to make it executable)
check_process() {
echo "$ts: checking $1"
[ "$1" = "" ] && return 0
[ `pgrep -f $1` ] && return 1 || return 0
#pgrep -n if process-name match exactly
}
while [ 1 ]; do
# timestamp
ts=`date +%T`
echo "$ts: begin checking..."
check_process "myprog.pl"
[ $? -eq 0 ] && echo "$ts: not running, restarting..." && `/usr/bin/perl /home/me/myprog.pl >/dev/null`
sleep 10 done
You can also send yourself a mail instead of just starting process instead of
/usr/bin/perl /home/me/myprog.pl
do
echo "Subject: Process is stopped" | sendmail yourmail@mail.com
If you want to run this in background do
nohup check_process.sh &
or you can put this on startup via cronjob
crontab -e
@reboot root /home/me/check_process.sh
Origin/Source: https://stackoverflow.com/questions/7708715/check-if-program-is-running-with-bash-shell-script
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net use with which user?
If you have to find out who has mapped a network drive in Windows start a Command prompt and type
wmic netuse where LocalName="X:" get Username /value
replace „X:“ with the drive you want.
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Treesize for Linux (bulitin)
Lack of free space? just type in
du -sk *|sort -n
on /
or any folder you like. You will get an information about space occupation where you can investigate further.
Sample output:
0 fastboot 0 proc 0 sys 4 boot 4 dev 4 lib64 4 media 4 mnt 4 srv 8 aquota.user 8 home 12 aquota.group 16 lost+found 120 tmp 644 run 6080 bin 7244 sbin 8544 etc 29076 lib 1345892 opt 1364796 usr 3028736 root 12280360 var
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YUM Cheat Sheet
The Yellowdog Updater, Modified (YUM) is a libre and open-source command-
Display yum commands and options
yum help
List all available packages
yum list available
List all installed packages
yum list installed
List installed and available packages
yum list all
List installed and available kernel packages
yum list kernel
List info about vsftpd package
yum info vsftpd
List dependencies and packages providing them
yum deplist nfs-utils
Show package that contains top command
yum provides “*bin/top”
Find packages with samba in name or description
yum search samba
Get info on available security updates
yum updateinfo security
Query repositories for available package updates
yum check-update
Download (no install) vsftpd package to cache (/var/cache/yum/arch/prod/repo/)
yum install --downloadonly vsftpd
Install the vsftpd package
yum install vsftpd
Update the httpd package (if available)
yum update httpd
Apply security-related package updates
yum update --security
Remove httpd and other unneeded packages
yum autoremove httpd
Remove the vsftpd package and dependencies
yum remove vsftpd
Downgrade the abc package to an earlier version
yum downgrade abc
Delete packages saved in cache
yum clean packages
List installed RPM packages and statistics
show-installed
For more check: https://access.redhat.com/sites/default/files/attachments/rh_yum_cheatsheet_1214_jcs_print-1.pdf
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