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Sync MySQL Servers via secure SSH-tunnel

I wanted to keep a backup of my company database server on my local homeserver. After I found maatkit to sync databases, everything except security seemed fine. SSH takes care of that part.
This is sample output - yours may be different.
7

ssh -f -L3307:127.0.0.1:3306 -N -t -x user@host sleep 600 ; mk-table-sync --execute --verbose u=root,p=xxx,h=127.0.0.1,P=3307 u=root,p=xxx,h=localhost

erlebnishengst · 2009-09-04 16:54:25 11
When was your OS installed?

shows also time if its the same year or shows year if installed before actual year and also works if /etc is a link (mac os) Show Sample Output
This is sample output - yours may be different.
```
Jul 15 11:46
or
Dec 24 2006
```
5

ls -lct /etc/ | tail -1 | awk '{print $6, $7, $8}'

peshay · 2009-09-04 16:52:50 5
Make a statistic about the lines of code

Have wc work on each file then add up the total with awk; get a 43% speed increase on RHEL over using "-exec cat|wc -l" and a 67% increase on my Ubuntu laptop (this is with 10MB of data in 767 files).
This is sample output - yours may be different.
-1

find . -type f -name '*.c' -exec wc -l {} \; | awk '{sum+=$1} END {print sum}'

arcege · 2009-09-04 15:51:30 6
Floating point power p of x

One pipe less. Show Sample Output
This is sample output - yours may be different.
```
1.41421356237309504878
```
1

bc -l <<< "x=2; p=0.5; e(l(x)*p)"

akg240 · 2009-09-04 15:50:48 5
bash function to check for something every 5 seconds

Every seconds do Show Sample Output
This is sample output - yours may be different.
```
Every 10,0s: ls /tmp                           Fri Sep  4 19:19:11 2009
...
<list of files>
```
-1

watch -n <seconds> <command>

aonick · 2009-09-04 15:19:42 3
badblocks for floppy
This is sample output - yours may be different.
0

/sbin/badblocks -v /dev/fd0 1440

opexxx · 2009-09-04 09:28:52 13
show all upd tcp an icmp traffic but ssh
This is sample output - yours may be different.
-2

tcpdump -n -v tcp or udp or icmp and not port 22

opexxx · 2009-09-04 09:23:52 4
Ultimate current directory usage command

Based on the MrMerry one, just add some visuals to differentiate files and directories
This is sample output - yours may be different.
3

du -a --max-depth=1 | sort -n | cut -d/ -f2 | sed '$d' | while read i; do if [ -f $i ]; then du -h "$i"; else echo "$(du -h --max-depth=0 "$i")/"; fi; done

nickwe · 2009-09-03 20:43:43 3
Ultimate current directory usage command

An NCurses version of the famous old 'du' unix command
This is sample output - yours may be different.
20

ncdu

nickwe · 2009-09-03 20:38:32 15
Ultimate current directory usage command

Based on the MrMerry one, just add some visuals and sort directory and files
This is sample output - yours may be different.
2

find . -maxdepth 1 -type d|xargs du -a --max-depth=0|sort -rn|cut -d/ -f2|sed '1d'|while read i;do echo "$(du -h --max-depth=0 "$i")/";done;find . -maxdepth 1 -type f|xargs du -a|sort -rn|cut -d/ -f2|sed '$d'|while read i;do du -h "$i";done

nickwe · 2009-09-03 20:33:21 5
How to watch files

To highlight the difference between screen updates
This is sample output - yours may be different.
0

watch -d 'ls -l'

0disse0 · 2009-09-03 20:12:36 3
Watching Command

If you need to keep an eye on a command whose output is changing, use the watch command. For example, to keep an eye on your load average
This is sample output - yours may be different.
1

watch 'cat /proc/loadavg'

0disse0 · 2009-09-03 20:10:46 4
See if your mac can run 64-bit && if it the kernel is loaded 64-bit
This is sample output - yours may be different.
0

ioreg -l -p IODeviceTree | grep -o EFI[0-9]. && system_profiler SPSoftwareDataType |grep 64

commandlinefu · 2009-09-03 19:58:44 3
Start a terminal with three open tabs

If you launch gnome-terminal manually, you can start with three open tabs
This is sample output - yours may be different.
2

gnome-terminal --tab --tab --tab

0disse0 · 2009-09-03 19:36:07 3

bash function to check for something every 5 seconds

checkfor: have the shell check anything you're waiting for. 'while : ; do' is an infinite loop '$*' executes the command passed in 'sleep 5' - change for your tastes, sleep for 5 seconds bash, ksh, likely sh, maybe zsh Ctrl-c to break the loop Show Sample Output

function checkfor () { while :; do $*; sleep 5; done; }

relay · 2009-09-03 19:35:42 6

Check the apt security keys

For example: check the APT security keys to make sure the Google digital signature was imported correctly Show Sample Output
This is sample output - yours may be different.
```
uid                  Google, Inc. Linux Package Signing Key
<linux-packages-keymaster@google.com>
sub   2048g/C07CB649 2007-03-08
```
0

apt-key list

0disse0 · 2009-09-03 19:32:11 3
How to know the total number of packages available
This is sample output - yours may be different.
4

apt-cache stats

0disse0 · 2009-09-03 19:29:17 3

Access to specific man page section

You can view the man pages from section five by passing the section number as an argument to the man command Show Sample Output

man 5 crontab

0disse0 · 2009-09-03 19:27:08 3

bash/ksh function: given a file, cd to the directory it lives

fcd : file change directory A bash function that takes a fully qualified file path and cd's into the directory where it lives. Useful on the commadline when you have a file name in a variable and you'd like to cd to the directory to RCS check it in or look at other files associated with it. Will run on any ksh, bash, likely sh, maybe zsh. Show Sample Output
This is sample output - yours may be different.
```
# assume EVN is setup - adding for context.
cd 
postmaster=${HOME}/Mail/2009/Aug/System/postmaster
mkdir -p $(dirname $postmaster) ; touch $postmaster
##
fcd $postmaster
/home/smith/Mail/2009/Aug/System
```
1

function fcd () { [ -f $1 ] && { cd $(dirname $1); } || { cd $1 ; } pwd }

relay · 2009-09-03 18:58:13 11
Edit all files found having a specific string found by grep

Make sure that find does not touch anything other than regular files, and handles non-standard characters in filenames while passing to xargs.
This is sample output - yours may be different.
-1

find . -type f -exec grep -qi 'foo' {} \; -print0 | xargs -0 vim

arcege · 2009-09-03 17:55:26 7
Run a bash script in debug mode, show output and save it on a file

Sends both stdout and stderr to the pipe which captures the data in the file 'out.test' and sends to stdout of tee (likely /dev/tty unless redirected). Works on Bourne, Korn and Bash shells.
This is sample output - yours may be different.
4

bash -x test.sh 2>&1 | tee out.test

arcege · 2009-09-03 17:10:44 3
floating point operations in shell scripts
This is sample output - yours may be different.
-8

echo $((3.0/5.0))

andrew112358 · 2009-09-03 16:35:09 7
Edit all files found having a specific string found by grep

needs no GNU tools, as far as I see it
This is sample output - yours may be different.
-1

find . -exec grep foobar /dev/null {} \; | awk -F: '{print $1}' | xargs vi

verboEse · 2009-09-03 16:02:18 3
Edit all files found having a specific string found by grep

saves one command. Needs GNU grep though :-(
This is sample output - yours may be different.
0

grep -ir 'foo' * | awk -F '{print $1}' | xargs vim

verboEse · 2009-09-03 15:58:47 3
Edit all files found having a specific string found by grep

The grep switches eliminate the need for awk and sed. Modifying vim with -p will show all files in separate tabs, -o in separate vim windows. Just wish it didn't hose my terminal once I exit vim!!
This is sample output - yours may be different.
3

grep -Hrli 'foo' * | xargs vim

dere22 · 2009-09-03 15:44:05 12
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host - DNS lookup utility

host is a simple utility for performing DNS lookups. It is normally used to convert names to IP addresses and vice versa. When no arguments or options are given, host prints a short summary of its command line arguments and options.

send echo to socket network

Using netcat, usuallly installed on debian/ubuntu. Also to test against a sample server the following two commands may help echo got milk? | netcat -l -p 25 python -c "import SocketServer; SocketServer.BaseRequestHandler.handle = lambda self: self.request.send('got milk?\n'); SocketServer.TCPServer(('0.0.0.0', 25), SocketServer.BaseRequestHandler).serve_forever()"

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"

coloured tail

tail with coloured output with the help of perl - need more colours? here is a colour table: http://www.tuxify.de/?p=23

Find and display most recent files using find and perl

This pipeline will find, sort and display all files based on mtime. This could be done with find | xargs, but the find | xargs pipeline will not produce correct results if the results of find are greater than xargs command line buffer. If the xargs buffer fills, xargs processes the find results in more than one batch which is not compatible with sorting. Note the "-print0" on find and "-0" switch for perl. This is the equivalent of using xargs. Don't you love perl? Note that this pipeline can be easily modified to any data produced by perl's stat operator. eg, you could sort on size, hard links, creation time, etc. Look at stat and just change the '9' to what you want. Changing the '9' to a '7' for example will sort by file size. A '3' sorts by number of links.... Use head and tail at the end of the pipeline to get oldest files or most recent. Use awk or perl -wnla for further processing. Since there is a tab between the two fields, it is very easy to process.

Get AWS temporary credentials ready to export based on a MFA virtual appliance

You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

netcat as a portscanner

Find the package that installed a command

Detect illegal access to kernel space, potentially useful for Meltdown detection

Based on capsule8 agent examples, not rigorously tested

convert filenames in current directory to lowercase

The simplest way I know.

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