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Tag: linux

Website Speed Test with Linux

If you own a Blog and want to check the Speed with your local Linux Computer use a commandline tool called curl. Open a Terminal and enter:   curl -o /dev/null -s -w 'Connect: %{time_connect}\nStart Transfer: %{time_starttransfer}\nTotal: %{time_total}\n' https://www.yourdomain.de System Echos: Connect: 0,084774 Start Transfer: 0,173280 Total: 0,228651 Advantage? You will see the Website Load Time of Users at your Location (Country Area) You can check “high performance Clouds” vs. “bare metal Servers” or “virtual Hosting” You see that mostly expensive Hosting is wasted money cause “shared” IO V-Host is SLOWER! You get the real “felt” IO for Users who […]

Openwrt dmesg human timestamp

To viel on busybox dmesg with human readable time for debug do: $vi /root/dmesg.sh insert: base=$(cut -d '.' -f1 /proc/uptime); seconds=$(date +%s); dmesg | sed 's/\]//;s/\[//;s/\([^.]\)\.\([^ ]*\)\(.*\)/\1\n\3/' | while read first; do read second; first=`date +"%d/%m/%Y %H:%M:%S" –date="@$(($seconds – $base + $first))"`; printf "[%s] %s\n" "$first" "$second"; done exit 0 run it sh dmesg.sh.. System Echo: … [16/03/2018 14:55:18] br-lan: port 3(wlan1) entered blocking state [16/03/2018 14:55:18] br-lan: port 3(wlan1) entered disabled state [16/03/2018 14:55:18] device wlan1 entered promiscuous mode [16/03/2018 14:55:18] br-lan: port 3(wlan1) entered blocking state [16/03/2018 14:55:18] br-lan: port 3(wlan1) entered forwarding state [16/03/2018 14:55:19] br-lan: port […]

Linux: Systemd ignore console-setup settings

If you work on older Laptops and you use a Console only System Setup like on Debian there is a Bug on systemd and the console-setup package since years. After reboot all Font Settings seems gone. But the Settings are not real gone, cause systemd does not pull the settings on boot! How to fix? edit the crontab of root by sudo su – crontab -e insert the /bin/setupcon command on “@reboot” means on every boot! @reboot     /bin/setupcon > /dev/null 2>&1 save and exit, reboot now now the PC should echo big Fonts for old eyes “Terminus 20×12 Frambuffermode”  

Security: Isolated Browser eMail Programs

If you want to be more secure, on Linux you can isolate used programs on different Users! All you need is installed by default! Howto: Add a new User for eMail and Browser to the System with: $sudo adduser mailuser $sudo adduser webuser now install if not installed by default “gksu” User Switch $sudo apt-get install gksu copy now the default App Links to webuser’s Home Desktop, for mailuser enter mailuser’s name $cp /usr/share/applications/firefox-esr.desktop /home/webuser/Desktop/firefox-esr.desktop edit the firefox-esr.desktop by right click on nautilus or a editor and change command line: old: /usr/lib/firefox-esr/firefox-esr %u to: gksu -u webuser -w "/usr/lib/firefox-esr/firefox-esr %u" […]

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 […]

Debian: Update SSD Firmware without CDROM

If you want to update the SSD Firmware of a device you should know some things: Do you REALLY need the update? Bugs? If NOT exit here! Firmwareupdates can destroy DATA on Drives! Data cant be restored if the Controller fails after Update Downgrade a Firmware to older is most IMPOSSIBLE!! .. now you need a USB Stick 4GB and the ISO File of the Firmware Disk of the Manufacter then open the Gnome Terminal or Console and: $sudo su – #become root $apt-get update && apt-get install unetbootin gparted # install the tools $dd if=/dev/null of=/dev/sdc bs=10240 count=1 # […]

Ubuntu Debian Samsung SSD secure erase with Linux

If you use a Samsung (possible others brands same howto) SSD and you want to secure erase the SSD for reuse or resale (better destroy it!!!) do: Insert your Debian/Ubuntu Setup CD/Stick Boot into Live/Setup Mode open Gnome Terminal or Console and enter $sudo su – #to be root then enter.. $ apt-get update && apt-get install hdparm # get the tool $ sudo fdisk -l # show drives $ sudo hdparm -I /dev/sda #show drive Infos and lock for "frozen" state!!! shoud be not frozen/locked $ sudo hdparm –security-set-pass NULL /dev/sdb # set the "NULL" password to UNLOCK the […]

Debian: Auto Update System Daily without special Tools

If you want to have a full automatic Update on your System then open a Gnome Terminal / Linux Console run (# Comments): $sudo nano /root/update.sh enter: #/!bin/bash apt-get update #pull updates apt-get dist-upgrade -y # install updates apt-get clean #clean update database for next pull to have clean source urls exit 0 save with CTRL+X # save+Exit $sudo chmod 755 /root/update.sh # make able to run Setup Timeplan: $sudo su –  # change to root users console with environment $crontab -e  # open root timer enter: @daily sh /root/update.sh > /dev/null 2>&1 save with CTRL+X and be happy the […]

Ubuntu: Recover Data from old Luks Encrypted HDD to new HDD

If you prefer to use encrypted Devices you ran into a problem if you try to move, migrate or recover the files from the old luks protected home. As normal User you should know that luks is used with LVM2 Logicial Volume Manager, which manages the partitions “named based”. Major Info! Ubuntu prename the volume group with the Setup-DVD all time to the same VG_NAME called “ubuntu-vg”!!! So what do you need to migrate or recover? Download the ubuntu DVD and burn it to a disc Insert the new HDD to the Sata1 Port Plugin the ubuntu DVD for Setup […]

Linux Tip: Split Console Screen on Widescreen Laptop / PCs with “screen” and “terminator”

Current Laptops / PCs uses 16:9 Widescreen Displays and if you dont want to use Xorg (Gnome,unity,Openbox Desktops) you can use on Linux Console the program called “screen” it offers: – Split Consoles horizontally and vertically – disconnect the screen and let the scripts/commands active on remote Systems – reconnect if the remote Session was broken cause network problems On Gnome or unity you can use “terminator” see: – manpage of screen – http://unix.stackexchange.com/questions/7453/how-to-split-the-terminal-into-more-than-one-view