Michael Starks mstarks01

## Mastodon
<a rel="me" href="https://noc.social/@libr8r">Mastodon</a>

## bash_skeleton.sh
#!/bin/bash

# Exit if any variables are unset. May need to be uncommented if trying to expand positional parameters.
set -u
# Try to catch errors, but beware that some non-zero conditions are OK
set -e
# Capture errors within a pipeline
set -o pipefail

## bash error function
# From: https://google.github.io/styleguide/shellguide.html

err() {
  echo "[$(date +'%Y-%m-%dT%H:%M:%S%z')]: $*" >&2
}

if ! do_something; then
  err "Unable to do_something"
  exit 1
fi

## trap_ctrl_c.sh
# Credit: https://www.loggly.com/install/configure-linux.sh

#trapping Control + C
#these statements must be the first statements in the script to trap the CTRL C event

trap ctrl_c INT

function ctrl_c() {
  # Do something here
  exit 1

## config_tuned.sh
#!/usr/bin/env bash

profile=network-throughput

# Usage: die message ...
die() {
  printf '%s\n' "$*" >&2
  exit 1
}

## relabel_selinux.txt
From: https://access.redhat.com/solutions/24845

set SELINUX=permissive in /etc/selinux/config
Run fixfiles onboot or touch /.autorelabel
reboot
check the /var/log/messages and /var/log/audit/audit.log for new SELinux messages
set SELINUX=enforcing in /etc/selinux/config
Run fixfiles onboot or touch /.autorelabel
reboot

## bind_mount_in_chroot.txt
cd /mnt/foo
mount -t proc /proc proc/
mount --rbind /sys sys/
mount --rbind /dev dev/

## iptables-cheatsheet.md

      
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                mstarks01
                / iptables-cheatsheet.md
            
            
              Created
              July 13, 2021 21:02
                — forked from mcastelino/iptables-cheatsheet.md
            
              
                iptables-cheatsheet
              
          
    The netfilter hooks in the kernel and where they hook in the packet flow

The figure below calls out

The netfilter hooks
The order of table traversal


## log_all_commands.txt
Source: Matt Springfield. Original source unknown.

In /etc/bashrc (or profile):

export PROMPT_COMMAND='RETRN_VAL=$?;logger -p local6.debug "$(whoami) [$$]: $(history 1 | sed "s/^[ ]*[0-9]\+[ ]*//" ) [$RETRN_VAL]"'


For rsyslog: in /etc/rsyslog.d/bash.conf:

Local6.*                /var/log/commands.log (or wherever you want to send the data)

## escaping_json.txt
Source: https://www.sitepoint.com/basics-json-syntax-tips/

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	#!/bin/bash

	# Exit if any variables are unset. May need to be uncommented if trying to expand positional parameters.
	set -u
	# Try to catch errors, but beware that some non-zero conditions are OK
	set -e
	# Capture errors within a pipeline
	set -o pipefail
	# From: https://google.github.io/styleguide/shellguide.html

	err() {
	echo "[$(date +'%Y-%m-%dT%H:%M:%S%z')]: $*" >&2
	}

	if ! do_something; then
	err "Unable to do_something"
	exit 1
	fi
	# Credit: https://www.loggly.com/install/configure-linux.sh

	#trapping Control + C
	#these statements must be the first statements in the script to trap the CTRL C event

	trap ctrl_c INT

	function ctrl_c() {
	# Do something here
	exit 1
	#!/usr/bin/env bash

	profile=network-throughput

	# Usage: die message ...
	die() {
	printf '%s\n' "$*" >&2
	exit 1
	}
	From: https://access.redhat.com/solutions/24845

	set SELINUX=permissive in /etc/selinux/config
	Run fixfiles onboot or touch /.autorelabel
	reboot
	check the /var/log/messages and /var/log/audit/audit.log for new SELinux messages
	set SELINUX=enforcing in /etc/selinux/config
	Run fixfiles onboot or touch /.autorelabel
	reboot
	cd /mnt/foo
	mount -t proc /proc proc/
	mount --rbind /sys sys/
	mount --rbind /dev dev/
	Source: Matt Springfield. Original source unknown.

	In /etc/bashrc (or profile):

	export PROMPT_COMMAND='RETRN_VAL=$?;logger -p local6.debug "$(whoami) [$$]: $(history 1 \| sed "s/^[ ][0-9]\+[ ]//" ) [$RETRN_VAL]"'


	For rsyslog: in /etc/rsyslog.d/bash.conf:

	Local6.* /var/log/commands.log (or wherever you want to send the data)
	Source: https://www.sitepoint.com/basics-json-syntax-tips/

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