Commands by gdelfino (3)

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check open ports without netstat or lsof

Remove invalid key from the known_hosts file for the IP address of a host
Quick shortcut if you know the hostname and want to save yourself one step for looking up the IP address separately.

Automatic ssh Session Logger
A wrapper around ssh to automatically provide logging and session handling. This function runs ssh, which runs screen, which runs script. . The logs and the screen session are stored on the server. This means you can leave a session running and re-attach to it later, or from another machine. . . Requirements: * Log sessions on a remote server * Transparent - nothing extra to type * No installation - nothing to copy to the server beforehand . Features: * Function wrapper delegating to ssh - so nothing to remember - uses .ssh/config as expected - passes your command line option to ssh * Self-contained: no scripts to install on the server * Uses screen(1), so is: - detachable - re-attachable - shareable * Records session using script(1) * Configurable log file location, which may contain variables or whitespace L="$HOME" # local variable L="\$HOME" # server variable L="some space" . Limitations: * Log dir/file may not contain '~' (which would require eval on the server) . . The sessions are named by the local user connecting to the server. Therefore if you detach and re-run the same command you will reconnect to your original session. If you want to connect/share another's session simply run: $ USER=bob ssh [email protected] . The command above is stripped down to an absolute minimum. A fully expanded and annotated version is available as a Gist (git pastebin): https://gist.github.com/flatcap/3c42326abeb1197ee714 . If you want to add timing info to script, change the command to: $ ssh(){ L="\$HOME/logs/$(date +%F_%H:%M)-$USER";/usr/bin/ssh -t "[email protected]" "mkdir -p \"${L%/*}\";screen -xRRS $USER script --timing=\"$L-timing\" -f \"$L\"";}

Search $PATH for a command or something similar
Searches your $PATH for whatever you substitute for bash, though not sure if this will work if you substitute a different shell for bash!

Execute a command with a timeout

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Android PNG screenshot
Works with *rooted* Android devices. 400x800 are the screen dimensions of a typical handheld smartphone.

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Find out which process uses an old lib and needs a restart after a system update
Shows the full output of lsof.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"


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