sudo apt install libav-tools webm to mp4 http://askubuntu.com/questions/323944/convert-webm-to-other-formats ffmpeg -i “Jurjak – Bucuresti.webm” -qscale 0 “Jurjak – Bucuresti.mp4” ffmpeg -fflags +genpts -i “Jurjak – Bucuresti.webm” -r 24 “Jurjak – Bucuresti1.mp4” -> change to 24 FPS ffmpeg -i “Jurjak – Bucuresti.webm” […]
Linux hardware information
# sources: # http://askubuntu.com/questions/18372/how-can-i-find-out-what-ram-a-computer-system-has RAM sudo lshw -short -C memory sudo lshw -C memory sudo dmidecode -t memory VGA memory sudo dmesg | grep Reserving [ 0.000000] Reserving Intel graphics stolen memory at 0x5ef00000-0x7eefffff compute now using a hexadecimal calculator […]
Linux youtube downloader errors
first, let’s see the youtube-dl error youtube-dl https://www.youtube.com/playlist?list=PLEmVsSEEP5HDTSik5ZSyOWz0qsS1tPos_ [youtube:playlist] PLEmVsSEEP5HDTSik5ZSyOWz0qsS1tPos_: Downloading webpage [download] Downloading playlist: cantece pt copii in germana [youtube:playlist] playlist cantece pt copii in germana: Downloading 6 videos [download] Downloading video 1 of 6 [youtube] dtZ7U7csvcw: Downloading webpage […]
Comments on Angular 2 router guide
https://angular.io/docs/ts/latest/guide/router.html#!#resolve-guard CanDeactivateGuard is used in CrisisCenterRoutingModule which is part of CrisisCenterModule which is lazy loaded by AppRoutingModule (loadChildren: ‘app/crisis-center/crisis-center.module#CrisisCenterModule’). q: Why should CanDeactivateGuard be declared in AppRoutingModule providers? why not to CrisisCenterRoutingModule providers? guide answer: We also need to add […]
X server and related managers
See also # nice explanation about the entire startx workflow http://unix.stackexchange.com/questions/243195/what-desktop-environment-does-startx-run-and-how-can-i-change-it # explanation about sessions http://askubuntu.com/questions/62833/how-do-i-change-the-default-session-for-when-using-auto-logins # list available desktop environments ls -l /usr/share/xsessions # show current login/display manager cat /etc/X11/default-display-manager # see also lightdm-greeter from Alternatives Configurator: ls -l […]
lsof
What files are open? lsof What process has a particular file open? lsof /path/to/the/file What files in some directory are open? lsof +D /path/to/the/dir What files does some user have open? lsof -u username What files do a group of […]
Linux useful links
wattOS (About page) wattOS Energizes Aging Hardware Non-Linux FOSS: Scripts in Your Menu Bar! VMware ESXi 6.0 / N3150 / J3160 ITX – Braswell platform http://mobiletiger.jorba.de/vmware-esxi-6-0-n3150-itx-intel-celeron-braswell-platform-problem-solved/
Plex Transcoding with low cost slow CPU
I have Ubuntu 16.04.1 LTS on this low power SoC board Asrock N3150DC-ITX with N3150 CPU: http://ark.intel.com/products/87258/Intel-Celeron-Processor-N3150-2M-Cache-up-to-2_08-GHz According to https://support.plex.tv/hc/en-us/articles/201774043-What-kind-of-CPU-do-I-need-for-my-Server- (see The Guideline) I quote: Very roughly speaking, for a single full-transcode of a video, the following PassMark scores are […]
Single Board Computers
Useful links http://eu.mouser.com/Mobile/Embedded-Solutions/Computing/Single-Board-Computers/_/N-aez3t/
Transmission on Ubuntu
Important files /etc/init.d/transmission-daemon -> SysV service /etc/default/transmission-daemon -> run by /etc/init.d/transmission-daemon /********/.config/transmission-daemon -> CONFIG_DIR in /etc/default/transmission-daemon /********/.config/transmission-daemon/settings.json User and Group running transmission-daemon change to desired ones (e.g. USER=************) in /etc/init.d/transmission-daemon
Yahoo certificate error
ERROR (ubuntu + chromium) https://forums.yahoo.net/t5/Errors/NET-ERR-CERTIFICATE-TRANSPARENCY-REQUIRED-on-chromium-53/m-p/141922/highlight/true#M36857 ERR_CERTIFICATE_TRANSPARENCY_REQUIRED You cannot visit mail.yahoo.com right now because the website uses HSTS. SOLUTION (no logic here but working at 16 Nov 2016) https://www.quora.com/How-do-you-fix-the-privacy-error-in-Chrome-Your-connection-is-not-private On the page displaying this error, click anywhere on the page where […]
Boost website performance
install ab command sudo apt install apache2-utils ### configure /etc/sysctl.conf: # Uncomment the next line to enable TCP/IP SYN cookies # See http://lwn.net/Articles/277146/ # Note: This may impact IPv6 TCP sessions too net.ipv4.tcp_syncookies=0 # https://linux.die.net/man/5/proc # https://www.kernel.org/doc/Documentation/sysctl/fs.txt fs.file-max = 6815744 […]
Crossroads load balance and fail over utility
Original description Crossroads is an open source load balance and fail over utility for TCP based services. It is a daemon running in user space, and features extensive configurability, polling of back ends using ‘wakeup calls’, detailed status reporting, ‘hooks’ […]
Spring MVC
Async processing See Spring MVC Configuration which relates to Callable return type for controller’s method.
Spring security with kerberos
What is a keytab, and how do I use one? Introduction to Kerberos for Managers Crash Course to Kerberos Appendix D. Troubleshooting JAAS authentication with Kerberos http://www.roguelynn.com/words/explain-like-im-5-kerberos/ KDC = Kerberos Key Distribution Center TGT = Ticket Granting Ticket TGS = […]