Linux cheasheet
Pass result of awk into kill or another command
docker ps -a | grep houston | awk '{print $1}' | xargs docker rm
Search replace =enforcing to =permissive in file
sudo sed -i 's\=enforcing\=permissive\g' /etc/sysconfig/selinux
Get public key for example to https://google.com
$ openssl s_client -connect google.com:443 | openssl x509 -pubkey -noout
Timestamp to hours since start day
awk '$3/3600000-int($3/86400000)*24+3<13 {print $3, $2, $4}'
/3600000- unix time in hours units./86400000- unix time in days units.*24- start of today in hours units.+3- increase 3 hours to align to our timezone.
TCPDUMP Textual
tcpdump -A -iany port 8080 -w scoring-conf-req.tcpdump
Which process listens on port
lsof -n -i:4888 | grep LISTEN
-n causes it to run much faster (do not resolve host names)
iptables
/etc/sysconfig/iptables (iptables configuration)
allow remote connections to port 8140
-A INPUT -m state --state NEW -m tcp -p tcp --dport 8140 -j ACCEPT
-A: We are appending a rule.INPUT: The rule applies to incoming packets.-m tcp -p tcp --dport 8140: The rule applies totcpport 8140.ACCEPT: iptables should accept the packets.
reload iptables
sudo service iptables restart
list processes listening on sockets
netstat -tlp
l: listening
p: show process id.
Show users::groups in system
cat /etc/group
clipboard with commandline
pbcopy < ~/.ssh/id_rsa.pub
pbpaste > main.go
push pop directories
pushd ~/tmp; popd
background processes instead of tabs
ctrl-z # suspend process to background
jobs -l # list background
bg
fg
disown -h # disconnect from my user so when I terminate terminal I wont have it.
Installing local yum repository on centos 7
yum install vsftpd # => very secure ftpd.
systemctl enable vsftpd # => enable sftpd service.
systemctl start vsftpd # => start sftpd service.
yum install createrepo # => for creation of local repository.
mkdir /var/ftp/pub/localrepo # => this is where our local repo is.
cp -ar /mnt/Packages/*.* /var/ftp/pub/localrepo/ # => copy an existing repo to your localrepo.
vi /etc/yum.repos.d/localrepo.repo # => point to the local repo.
ITerm
# iterm Keyboard Shortcuts
ALT+CMD+A # => notify when command completes. (one time enable shell integration from menu)
https://www.unixmen.com/setup-local-yum-repository-centos-7/
resources