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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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Print every Nth line

Sometimes commands give you too much feedback. Perhaps 1/100th might be enough. If so, every() is for you. $ my_verbose_command | every 100 will print every 100th line of output. Specifically, it will print lines 100, 200, 300, etc If you use a negative argument it will print the *first* of a block, $ my_verbose_command | every -100 It will print lines 1, 101, 201, 301, etc The function wraps up this useful sed snippet: $ ... | sed -n '0~100p' don't print anything by default $ sed -n starting at line 0, then every hundred lines ( ~100 ) print. $ '0~100p' There's also some bash magic to test if the number is negative: we want character 0, length 1, of variable N. $ ${N:0:1} If it *is* negative, strip off the first character ${N:1} is character 1 onwards (second actual character).

Reduce PDF size

Find usb device in realtime

Using this command you can track a moment when usb device was attached.

Find usb device in realtime

Using this command you can track a moment when usb device was attached.

Ride another SSH agent

Must be done as root - will cause subsequent ssh connections to use the identities available via the [user]'s agent socket.

Get video information with ffmpeg

I used an flv in my example, but it'll work on any file ffmpeg supports. It says it wants an output file, but it tells what you want to know without one.

doing some floating point math

automount samba shares as devices in /mnt/

the middle command between the ; and ; is the vi commands that insert that line into the last line of the file, the esc with the carets is literally hitting the escape key, you have to have the smbfs package installed to do it, I use it to access my iTunes music on my mac from my linux PC's with amarok so I can play the music anywhere in the house. among other things, it allows you to access the files on that share from your computer anytime you're on that network.

Display a list of RPMs installed on a particular date

Find out which RPMs were installed on a particular date. These would (naturally) include update RPMs. This example shows searching for "Thu 05 Mar" (with grep). Alternatively, pipe it to less so you can search inside less (with less's neat text highlighting of the search term): rpm -qa --queryformat '%{installtime} \"%{vendor}\" %{name}-%{version}-%{release} %{installtime:date}\n' | less # (this example) search term: Thu 05 Mar

last.fm rss parser

you can just use one awk script to parse the rss feed. No need to pipe so many awk's and sed's. Its ugly and inefficient.

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