IT notes

stty

If reset can’t clean your terminal, give a try to: stty sane

tmux

Set window title: <c-b>, Get pannel number: <c-b>q Show clock: <c-b>t Move pane to a new window: <c-b>! Join panes: <c-b>: join-pane -s 0 -t 3 move pane 1 to window 3 <c-b>: join-pane -t :1 move current pane to window 1 Create a new session: <c-b>: new -s <name> List sessions: <c-b>s <c-b>w expanded Move pane to a another session: <c-b>m mark the pane <c-b>w go to the destination window/session <c-b>: join-pane or go to the pane you want to move, check the session name and windows you would like to move and try:

Block SSH on MacOS

To block incoming ssh connections, edit the /etc/pf.conf and add the following line at the bottom: block in log quick proto tcp from any to any port 22 You can use vim or use something like this: sudo sh -c "echo 'block in log quick proto tcp from any to any port 22' >> /etc/pf.conf" Then reload the pfrules: sudo pfctl -Fa -f /etc/pf.conf For this to work the firewall must be enabled.

Processlist

Run show processlist every second: mysqladmin -uroot -p -i 1 processlist -i 1 stands for interval one second

OSI TLS

Beside the OSI/model, there is also the TCP/IP Model: Link Layer Internet (IP) Layer Transport Layer Application OSI Model The OSI model has a bit more granularity. Physical Layer Data Link Layer Network Layer (IP) Transport Layer (TCP) Session Layer (TLS) Presentation Layer Application Layer (HTTP) TLS establishes an encrypted session. In the OSI model this is where TLS operates. It sets up its session, and adds a layer of encryption for the Application Layer (HTTP).

IRC

Change password password in irc: /msg nickserv set password <password>

combine two images

Combine in a single file 2 images: convert +append a.png b.png out.png -append will append vertically instead of horizontally (+)

LS_COLORS

To remove the blinking of symbolic links when doing ls in Linux: LS_COLORS="ln=35" export LS_COLORS That will set the ln=35 symbolic links to color purple. Params for LS_COLORS: di Directory fi File ln Symbolic Link pi Fifo file so Socket file bd Block (buffered) special file cd Character (unbuffered) special file or Symbolic Link pointing to a non-existent file (orphan) mi Non-existent file pointed to by a symbolic link (visible when you type ls -l) ex File which is executable (ie.

htpasswd

To create an htpasswd file (for htaccess “authentication”) using openssl: $ printf "foo:$(openssl passwd -apr1 PASSWORD)\n" >> .htpasswd If need to use crypt: $ printf "foo:$(openssl passwd -crypt PASSWORD)\n" >> .htpasswd

Git SSH

To create a git repository and access to it via ssh: $ ssh your.host $ mkdir my-new-repo $ cd my-new-repo $ git --bare init To access your repo (clone it): $ git clone ssh://[email protected]:2222/~user/my-new-repo