If you want to Travel to other Countries (Border-Control), you should know some things: Buy a older Acer Laptop with Micro SSD Harddisk and SATA CDROM Slot Buy a SATA CDROM Adaptor for 10$, open the Laptop and remove the SATA Drive put it into the SATA Adaptor Don’t put Screws into the Laptop to the Adaptorslot so that you can pull out quick the SSD drive Install Ubuntu Linux with LUKS Disk full encryption! DOWNLOAD here Buy a privacy Shield-Sticker onto the TFT To extend security use USB-WIFI Dongle for WIFI Connections! (MAC Address Spoofing) Or: Buy a older […]
Category: Raspian
Bug: XDM Login Manager fails start on Boot
Seen on ubuntu 22.04 after do-release-upgrade the xdm Login Manager fails to start, cause a old xdm.pid file hangs from last shutdown on “/run/xdm.pid”. XDM prevent start on a old PID File!! Workaround edit Roots crontab to purge it: sudo crontab -e @reboot rm -rf /run/xdm.pid > /dev/null 2>&1 quit and save with “:wq!” ..reboot
Ubuntu: Chromium install without snap
Howto: Remove all snaps and install chromium on ubuntu 20.XX-24.XX sudo snap remove "package-name" (first all gtk-XX,gnone-xx and all "base+core") sudo apt-get remove snap snapd sudo add-apt-repository ppa:xtradeb/apps (Answere Question ENTER) sudo apt-get update sudo apt-get install chromium
Major Bug: Backdoor inside XZ Libs / SSH Backdoor
Brand New: SSH Backdoor seen on Linux XZ-Libs published with Backdoor! Prio HIGH! (The Backdoor offers break out of a SSH Connection) Update your Systems! Read: Article/Post/Backdoor-XZ-SSH Ubuntu Report Debian Report
Linux: find files modified in special Month
If you want to free space on Backups you can use find to select a special month: find -newerct "1 Sep 2023" ! -newerct "1 DEC 2023" -delete This command removes files created from 01.Sep.2023 to 01.Dec.2023. ..very useful..
Major Tools for your IT Systems
A must “USE” in these insecure days: nmap Portscan Tool use nmap -PN IP-Address to check failed Firewall Settings! arp-scan Network Scan to find active devices iftop to detect traffic and used Ports on a physical network Interface! ps aux show active processes on a Linux System htop more human friendly Process Monitor iotop human friendly traffic monitor from CPU/RAM to Drives Daily check Error Logs! Use always Firewalls and Disk/File Encryption! Don’t trust Hardware Protection (TPM) Chips most do communicate by clean signals on copper which can be read out by hardware hacking or magnetic fields! NEVER leave Hardware […]
Script DNS Blocker DNSMASQ
If you tested pihole, you perhaps look for a smaller Command Line version? Install dnsmasq by: sudo apt-get install dnsmasq Here DNS Rule Injector Script (copy & paste): blocker.sh # www.linuxonlinehelp.eu 2019 # DNS Blocker for Small Linux with dnsmasq # #!/bin/bash # goto tmp (tmpfs) cd /tmp/ # get URL-Blocklists wget -O blocklist.txt https://v.firebog.net/hosts/Kowabit.txt # get Templates #SET Variables txt='blocklist.txt' IP='0.0.0.0' # set to 0.0.0.0 or to a Webserver with "white Page" showing Text "URL-blocked!! #merge URLs and redirect to wanted IP – Rule creation n=1; while read line; do echo 'address=/'$line'/$IP '>> 02-blocked1.conf ; n=$((n+1)); done < $txt […]
Split Files on embedded Linux Systems
If you run a embedded Linux PC like raspi often some Linux Commands fail without error messages, cause the hardware performance is low tech. Same i have seen on the split command.. to split a 50GB Photos-Archive File to 4Gb on a USB Drive i found out that: sudo split -b 4096m -d -u Photos.tgz Photos-Archive_ fix the job.. Cause option -u disable IO-Caching over the 2.0 USB Port to the RAM of the raspi that the Data of the Output Stream is written direct to the Drive.
Smartmontools unlisted Devices
If you use a Toshiba Canvio 3tb Drive at a raspi then smartmontools will not see the usb drive. Try: sudo smartctl -t long -d sat -s on /dev/sdb -t test long or short -d drive protocol sata = sat -s enforce smart which is off by the usb drive firmware wait XXX Minutes then: sudo smartctl -H -d sat -s on /dev/sdb get status..
Postfix: Automatic UFW Firewall Updates
If you use a Mail Server with Postfix you got daily Spam Attacks by Scripts: How to fix? Install ufw Firewall Run a Scanner Script as cronjob On Debian/Ubuntu: Install ufw: sudo apt-get update && sudo apt-get install ufw && sudo ufw enable && sudo ufw logging off Scan Script: sudo nano /home/user/firewall-update.sh: #!/bin/bash # scan rejected cat /var/log/mail.log | grep rejected | cut -d"[" -f3 | cut -d"]" -f1|grep -v '^$' > /tmp/firewall.txt # insert to Firewall while read line; do sudo ufw insert 1 deny from $line to any; done < /tmp/firewall.txt # scan "denied" cat /var/log/mail.log | […]
Linux Console: SSH Echo Last User LOGIN Info
If you use SSH Logins to your Systems, you perhaps want to know, who logged in last days and from which IP Address. Screenshot SSH Login Echo LAST Info: Howto: Open the .profile File at your Home with a Editor and enter: clear last -n 4 This will echo after login the last 4 Logins including the used IP’s To prevent Hackers to purge the lines set the .profile File “readonly” sudo chmod 444 .profile sudo chown root:root .profile
Raspberry Pi: Resize Shrink SDCard Image Clone Backup Noobs
If you own a raspberry pi, in some cases it is useful to shrink the sdcard, cause you need often not more than 8/16GB. What do you need and how to solve shinking or extending the OS: Hardware you need: 2 empty SDCards (Source + Dest.) 2 SDCard Adaptors Micro-SD to SD Fullsize 2 SD-USB Card Readers, i use them for stable work, cause USB SDCard Readers on Laptops often fails (Shared Sources) 1 Laptop with Ubuntu CD inside the CD-Rom or installed ubuntu with gparted Howto: Plug the Cards into the Adaptors and into the Readers, connect to the […]
Rasperry Pi: SD Card Partitions Layout Noobs Backup Restore
If you use a raspberry pi for projects which is shipped with a 8GB SDCard it is very useful to know basics about the root, file and recovery system on the preinstalled card. Major Basics about the Partitioning you find here To save time the raspberry pi offers possibility to run a Full Backup if the pi is ONLINE! Cause the OS is running from RAM like Live Mode! For Backup you need a USB to SDCard Reader with Adaptor Micro SD to SD, and a second SDCard i use 16GB Class 10 Plugin the new SDCard into the Adaptor and into […]
Amazon: Cloud Drive Sharing with NFS on Local Network as Photo Uploader Backup
Current the acd_cli tool for amazon drive mount offers no “fsid” (device /dev) point, that you cant export and share the amazon drive at your home local network. On the latest raspberry pi OS (jessie) you can use a small workaround to get a NFS Shared Amazon Cloud Backup Uploader (needs python3.4 !) install acd_cli tools, create the auth file (read) and run $ sudo acd_cli mount /amazoncloud now create a second Folder /sendtoamazon install nfs-kernel-Server and share this Folder with NFS exports to your LAN on the raspberrypi you can use a cron “move” Job running every 10 Minutes: #crontab -e */10 * […]
Raspberry Pi: Raspian disadvantages of embedded OS
The last 12 month have been a “golden” time of the upcomming embedded linux devices, but the custom OS’s offers some problems, you should know for projects: embedded PC’s like the ARM based pi2 / pi3 uses a own compiled OS not every known debian package is available not all compile scripts to rebuild are available on git slow performance can let you run into unuseable problems (heat, load, I/O), correct written scripts run into freezes without any error made by you! you should take time for a closer look at buying them calc the costs of non-x86 systems, later […]