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check open ports without netstat or lsof

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Summarize Apache Extended server-status to show longest running requests
Ever need to know why Apache is bogging down *right now*? Hate scanning Apache's Extended server-status for the longest running requests? Me, too. That's why I use this one liner to quickly find suspect web scripts that might need review. Assuming the Extended server-status is reachable at the target URL desired, this one-liner parses the output through elinks (rendering the HTML) and shows a list of active requests sorted by longest running request at the bottom of the list. I include the following fields (as noted in the header line): Seconds: How long the request is alive PID: Process ID of the request handler State: State of the request, limited to what I think are the relevant ones (GCRK_.) IP: Remote Host IP making the request Domain: Virtual Host target (HTTP/1.1 Host: header). Important for Virtual Hosting servers TYPE: HTTP verb URL: requested URL being served. Putting this in a script that runs when triggered by high load average can be quite revealing. Can also capture "forgotten" scripts being exploited such as "formmail.pl", etc.

Turn off your laptop screen on command
echo 'alias monitor_off="sleep 1; xset dpms force standby"' >> ~/.bash_aliases ; . ~/.bash_aliases # now monitor_off does what you think

Convert the contents of a directory listing into a colon-separated environment variable
Useful for making a CLASSPATH out of a list of JAR files, for example. Also: export CLASSPATH=.:$(find ./lib -name '*.jar' -printf '%p:')

Copy ssh keys to user@host to enable password-less ssh logins.
Alternative for machines without ssh-copy-id

Show current iptables rules, with line numbers

dstat- this command is powerful one to monitor system activity . It has combined the power of vmstat,iostat,mpstat,df,free,sar .
As mentioned in the summery that it is a powerful command to monitor system activity in great way. It has got the power of vmstat,iostat,mpstat,df,free and sar.Instead of firing each single command separately ,one can fire one single command to get all the info at once.But there is a way to get the individual information too. Please see the man page . You can get it from here : http://dag.wieers.com/home-made/dstat/

quickly backup or copy a file with bash
less symbols, tab completion. including # export SIMPLE_BACKUP_SUFFIX="_`date +%F`" in your .bashrc provides you to easily timestamp your files

List top 100 djs from https://djmag.com/top100djs


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