Linux Commands 3

# Check if Fail2Ban is Running
FAIL2BAN=`ps ax | grep fail2ban | grep -v grep | awk {'print $1'}` && if [ -n "$FAIL2BAN" ]; then printf "\n[INFO] Fail2Ban is running and the PID is %s\n\n" $FAIL2BAN; else printf "\n [INFO] Fail2Ban is not running\n\n"; fi
# alias to list hidden files of a folder
alias lh='ls -a | egrep "^\."'
# grep: find in files
egrep -in "this|that" *.dat
# Salty detailed directory listing...
ls -saltS [dirname]
# play all songs under current directory smoothly as background job
nice -n0 ls | mpg321 -@- &
# Cute, but we already had this figured out when the Linux kids were still slurp
ing down log-sized spliffs in the back of the microbus.ssh-keygen -R hostname
# Get My Public IP Address
lwp-dump http://www.boredomsoft.org/ip.php|grep Client
# Get colorful fortunes
cowsay `fortune` | toilet --metal -f term
# calculate the total size of files in specified directory (in Megabytes)
du -h <Directory>
# Recursive chmod all files and directories within the current directory
find . -name "*" -print0 | xargs -0 -I {} chmod 777 {}
# Read directory contents recursively
while read f;do echo "$f";done < <(find .)
# Get your external IP address
wget -O - -q ip.boa.nu
# Show the last movie/ebook that you have saw/read
ls -lAhutr
# Echo several blank lines
for i in `seq 1 100`;do echo;done
# byobu use
byobu
# Prefetch like apple devices
sudo apt-get install preload
# "Reset" file permissions
find . -type f -exec chmod 0644 {} \;
# Find different filetypes in current directory
find . -maxdepth 1 -type f -name '*.sh' -o -name '*.txt'
# Print only the odd lines of a file
awk '{if (NR % 2 == 1) print $0}' file.txt
# Equivalent of alias in cmd.exe: doskey (macros)
doskey l=dir /OD $*
# Check syntax of cron files (by restarting the service and checking the logs)
/etc/init.d/cron restart && tail -100 /var/log/syslog
# kill some pids without specific pid
kill -9 `ps aux | grep "search_criteria" | awk '{if ($2 != pid) print $2}'`
# Change password in list of xml files with for and sed
for i in `ls  *xml`; do  sed -e 's,oldpassword,newpassword,g' $i > $i.2 && mv -f $i.2 $i  ; done
# See a list of ports running
netstat -an | grep -i listen
# Wordpress - download latest, extract, and rename config file.
alias wordpress='mkdir wordpress && cd wordpress && wget http://wordpress.org/latest.tar.gz && tar -xvzf latest.tar.gz && mv wordpress/* . && rm -rf latest.tar.gz wordpress && cp wp-config-sample.php wp-config.php'
# Get all IPs via ifconfig
ifconfig | grep "inet [[:alpha:]]\+" | cut -d: -f2 | cut -d' ' -f2
# View facebook friend list [hidden or not hidden]
lynx -useragent=Opera -dump 'http://www.facebook.com/ajax/typeahead_friends.php?ninatodorovic&__a=1' |gawk -F'\"t\":\"' -v RS='\",' 'RT{print $NF}' |grep -v '\"n\":\"' |cut -d, -f2
# empty a file
echo > filename
# Install NMAP 5.0, short and sweet command to do it
sudo wget -c "http://nmap.org/dist/nmap-5.00.tar.bz2" && bzip2 -cd nmap-5.00.tar.bz2 | tar xvf - && cd nmap-5.00 && ./configure && make && sudo make install
# cleaning after python
find ~ -name "*.pyc" -exec rm {} \;
# find the difference in 2 files with grep (diff alternative)
grep -vf file1 file2