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SSH connection through host in the middle
This is sample output - yours may be different.
1

ssh -J user@reachable_host user@unreacheable_host

renich · 2019-08-14 17:29:45 0

Find all clients connected to HTTP or HTTPS ports

It finds, specifically, the connections to the HTTP and HTTPS ports as source ports. You can check for destination ports as well. Show Sample Output

ss -o state established '( dport = :http or sport = :https )'

renich · 2019-08-14 17:28:13 0

Check whether laptop is running on battery or cable

1 = on ac, 0 = on bat
This is sample output - yours may be different.
0

cat /sys/class/power_supply/AC/online

wuziduzi · 2019-08-13 21:31:00 0
Check whether laptop is running on battery or cable

Just an alternative for `acpi -b` Show Sample Output
This is sample output - yours may be different.
```
Discharging 46%
```
1

eval "$(printf "echo %s \$((%i * 100 / %i))\n" $(cat $(find /sys -name energy_now 2>/dev/null | head -1 | xargs dirname)/{status,energy_{now,full}}))%"

glaudiston · 2019-08-10 16:50:12 0
Using a single sudo to run multiple && arguments

Bash's here string
This is sample output - yours may be different.
4

sudo -s <<< 'apt update -y && apt upgrade -y'

metropolis · 2019-08-07 14:03:30 0
jump to home dir and list all, not older than 3 days, with full-path, hidden/non-hidden files/subdirectories

Number of days back: change/append arbitrary amount of '\|'$[$(date +%Y%j)-x] expressions or specify any n-th day before today for a single day (you have to replace x with 3, 4, 5, whatever ... above I replaced it with 1 and 2 to get listing for yesterday and day before yesterday and 0 for today was not necessary, so left out). Q: How to narrow to *.pdf , *.png, *.jpg, *.txt, *.doc, *.sh or any type of files only? A: Pipe to grep at the end of command. Even shorter: cd && day=3;for a in $(seq $day -1 0);do tree -aicfnF --timefmt %Y%j-%d-%b-%y|grep $[$(date +%Y%j)-$a];done Here it's only needed to change amount of variable day to list period of days back - here is set to three days back (the seq command is adjusted for listing the oldest stuff first). Show Sample Output
This is sample output - yours may be different.
```
[2019215-03-Aug-19]  ./.config/session/
[2019215-03-Aug-19]  ./.config/session/konsole_2b5b0f704-9942-428b-a3d8-8054efd32b18_1564837706_57870
[2019215-03-Aug-19]  ./.config/session/konsole_23e1f9567-a8ff-42ad-a879-76f7bafb56c3_1564840981_89854
[2019215-03-Aug-19]  ./.config/session/konsole_2e2aea661-fd41-4510-b0b9-1d2c69ef99c7_1564864156_611707
[2019215-03-Aug-19]  ./.config/konsolerc
[2019216-04-Aug-19]  ./.config/dconf/
[2019216-04-Aug-19]  ./.config/dconf/user
[2019216-04-Aug-19]  ./.config/briši_me.pdf
```
0

cd && tree -aicfnF --timefmt %Y%j-%d-%b-%y|grep $(date +%Y%j)'\|'$[$(date +%Y%j)-1]'\|'$[$(date +%Y%j)-2]

knoppix5 · 2019-08-04 02:22:24 0
Remove abstracts from a bibtex file

Remove lines from a bibtex file that have abstracts in them.
This is sample output - yours may be different.
0

sed '/^\s*abstract\s*=\s*{[^\n]*},$/ d' input.bib > output.bib

mirams · 2019-08-01 13:59:38 1
Using a single sudo to run multiple && arguments

This will also work with bash instead of sh shell sudo bash -c 'apt update -y && apt upgrade -y'
This is sample output - yours may be different.
0

sudo sh -c 'apt update -y && apt upgrade -y'

ioshield · 2019-07-31 04:39:40 0
shell bash iterate number range with for loop

"seq" has an additional parameter to use as INCREMENT. # seq FIRST INCREMENT LAST https://linux.die.net/man/1/seq Show Sample Output
This is sample output - yours may be different.
```
1
2
3
4
5
```
0

for i in $(seq 1 5) ; do echo $i ; done

guilsson · 2019-07-29 18:34:12 0
shell bash iterate number range with for loop
This is sample output - yours may be different.
0

seq 10 20

Thierry · 2019-07-28 21:47:07 0
Faciliate the work for lftp ('all' is needed if you wanna use it with getopts, otherwise its enough with the lftp line)

Add this to a script and you can do ./scriptname site help or ./scriptname mput etc etc.
This is sample output - yours may be different.
0

all="$(echo -e $*|awk '{for(i=3;i<=NF;++i)print $i}'|xargs)"; lftp -e open <HOSTNAME> -p <PORT> -u <USER>:<PASSWORD> -e "$all;exit"

wuziduzi · 2019-07-28 18:48:28 0
Block all brute force attacks in realtime (IPv4/SSH)

Was to long with a loop, use a while loop for have it running 24/7
This is sample output - yours may be different.
0

inotifywait -r -q --format %w /var/log/auth.log|grep -i "Failed pass"|tail -n 1|grep -oE '\b([0-9]{1,3}\.){3}[0-9]{1,3}';iptables -I INPUT -i eth0 -s "$(cat /var/log/auth.log|grep "authentication failure; l"|awk -Frhost= '{print $2}'|tail -n 1)" -j DROP

wuziduzi · 2019-07-28 18:42:23 1
Block all IPv4 addresses that has brute forcing our ssh server

For ipv6 use: grep -oE "\b([0-9A-Fa-f]{1,4}:){7}[0-9A-Fa-f]{1,4}\b"
This is sample output - yours may be different.
0

for idiots in "$(cat /var/log/auth.log|grep invalid| grep -oE '\b([0-9]{1,3}\.){3}[0-9]{1,3}\b')"; do iptables -A INPUT -s "$idiots" -j DROP; done

wuziduzi · 2019-07-28 18:29:14 1
shell bash iterate number range with for loop

Bash's arithmetic evaluation.
This is sample output - yours may be different.
1

for((i=1;i<=10;i++)){ echo $i; }

metropolis · 2019-07-28 02:32:09 0
shell bash iterate number range with for loop
This is sample output - yours may be different.
1

for i in {1..10}; do echo $i; done

bakhru · 2019-07-28 01:09:35 0
Which processes are listening on a specific port (e.g. port 80)
This is sample output - yours may be different.
0

netstat -nap|grep 80|grep LISTEN

bakhru · 2019-07-28 01:08:45 0
shell bash iterate number range with for loop
This is sample output - yours may be different.
0

rangeBegin=10; rangeEnd=20; for ((numbers=rangeBegin; numbers<=rangeEnd; numbers++)); do echo $numbers; done

forouharid · 2019-07-27 21:04:27 0
shell bash iterate number range with for loop

iterating range of numer with for loop in shell or bash Show Sample Output
This is sample output - yours may be different.
```
10
11
12
13
14
15
16
17
18
19
20
```
-1

rangeBegin=10; rangeEnd=20; for numbers in $(eval echo "{$rangeBegin..$rangeEnd}"); do echo $numbers;done

aysadk · 2019-07-26 09:19:44 1
bash test check validate if variable is number

to test check if given variable is a digit / number Show Sample Output
This is sample output - yours may be different.
```
error: Not a number
```
1

varNUM=12345; re='^[0-9]+$'; if ! [[ $varNUM =~ $re ]] ; then echo "error: Not a number"; fi

aysadk · 2019-07-26 09:15:37 1
iso to USB with dd and show progress status

Does the same but shows nicely progress in real time with correct Size in %. But also needs the packages sudo,dd,pv and dialog.
This is sample output - yours may be different.
0

image="file.iso";drive="/dev/null";sudo -- sh -c 'cat '"${image}"'|(pv -n -s $(stat --printf="%s" '"${image}"')|dd of='"${drive}"' obs=1M oflag=direct) 2>&1| dialog --gauge "Writing Image '"${image}"' to Drive '"${drive}"'" 10 70 7'

fries · 2019-07-25 11:11:45 0
Stage all files for commit except those that are *.config at any level within your git repo [Windows]
This is sample output - yours may be different.
0

git status | Where-Object {$_.Contains('modified') -and !$_.Contains('.config')} | ForEach-Object { git add $_.Replace('modified:','').Trim() }

RaphHaddad · 2019-07-22 06:25:45 0
Delete all local branches that have been merged into master [Windows]
This is sample output - yours may be different.
-1

git branch --merged origin/master | Where-Object { !$_.Contains('master') } | ForEach-Object { git branch -d $_.trim() }

RaphHaddad · 2019-07-22 06:24:55 0
Initialise git in working directory with latest Visual Studio .gitignore [Windows]
This is sample output - yours may be different.
-1

git init; (Invoke-WebRequest https://raw.githubusercontent.com/github/gitignore/master/VisualStudio.gitignore -UseBasicParsing).Content | Out-File -FilePath .gitignore -Encoding utf8; git add -A

RaphHaddad · 2019-07-22 06:24:33 0
Line Separator That is Width of Terminal

Creates a line seperator that will be the width of your window. Show Sample Output
This is sample output - yours may be different.
```
???? CL test                                                                                         
============================================== test ==============================================
```
1

CL () { WORDS=$@; termwidth="$(tput cols)"; padding="$(printf '%0.1s' ={1..500})"; printf '%*.*s %s %*.*s\n' 0 "$(((termwidth-2-${#WORDS})/2))" "$padding" "$WORDS" 0 "$(((termwidth-1-${#WORDS})/2))" "$padding"; }

Sabz69 · 2019-07-20 20:39:10 2
pretty print json block that has quotes escaped
This is sample output - yours may be different.
0

echo 'json_here' | sed 's/\\//g' | jq .

jgleeson · 2019-07-19 16:26:48 0
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Email an svn dump

Dumps a compressed svn backup to a file, and emails the files along with any messages as the body of the email

Use the builtin ':' bash command to increment variables

I just found another use for the builtin ':' bash command. It increments counters for me in a loop if a certain condition is met... : [arguments] No effect; the command does nothing beyond expanding arguments and performing any specified redirections. A zero exit code is returned.

Changes standard mysql client output to 'less'.

Changes standard mysql client output to 'less'. In another words makes query results of mysql command line client to look much better.

Get decimal ascii code from character

printf treats first char after single ' as numeric equivalent

Find broken symlinks

Migrate Server with rsync

Copies the complete root-dir of a linux server to another one, where the new harddisks formated and mountet. Very useful to migrate a root-server to another one.

Copy a folder tree through ssh using compression (no temporary files)

This command will copy a folder tree (keeping the parent folders) through ssh. It will: - compress the data - stream the compressed data through ssh - decompress the data on the local folder This command will take no additional space on the host machine (no need to create compressed tar files, transfer it and then delete it on the host). There is some situations (like mirroring a remote machine) where you simply cant wait for a huge time taking scp command or cant compress the data to a tarball on the host because of file system space limitation, so this command can do the job quite well. This command performs very well mainly when a lot of data is involved in the process. If you copying a low amount of data, use scp instead (easier to type)

Server load and process monitoring

In certain cases you mighy need to monitor the server load caused by certain process. For example HTTP, while stress testing apache using ab (apache benchmark) you may want to monitor the server status,load, # of spawned HTTP processes, # of established connections, # of connections in close wait state, apache memory footprint etc.

Show all available colors on your terminal.

Using perl and tput, show all the colors with numbers that your actual $TERM can handle. If want to remove the numbers at beginning of new line, it should be something like this: $perl -E 'say `tput setb $_`," "x `tput cols`, `tput sgr0` for 0 .. (`tput colors` - 1)'

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