# Linux

# Linux command

command	Description
pstree	Display tree of processes
hostname	Show or set the system's host name
hostname -I	Show all network addresses of the host
nmap -p <port> <address>	Ping specific port
ab -n <number> http://localhost:80/	Perform <number> requests on specific url (apt install apache2-utils)

# Linux tutorials

https://linuxize.com/post/how-to-set-up-ssh-keys-on-ubuntu-1804/

and

# grep Password /etc/ssh/sshd_config

PermitEmptyPasswords no PasswordAuthentication no

https://www.digitalocean.com/community/tutorials/how-to-partition-and-format-storage-devices-in-linux

https://www.youtube.com/watch?v=pJF83mSllWE

https://medium.com/swlh/postgresql-replication-with-docker-c6a904becf77

How to open ports in linux

SELECT pg_reload_conf(); - reload pg_hba.conf

psql -h <ip_add> -p -d <db_name> -U - pripojenie sa na vzdialenu databazu

https://github1s.com/

https://confluence.jaytaala.com/display/TKB/Create+a+persistent+SSH+tunnel+between+servers+with+systemd

https://devconnected.com/how-to-ping-specific-port-number/

https://www.brandonchecketts.com/archives/creating-a-permanent-ssh-tunnel-between-linux-servers

https://vsupalov.com/docker-shared-permissions/

RESIZE disk on VM https://www.networkshinobi.com/proxmox-linux-vm-template/

https://forum.proxmox.com/threads/resize-disk-of-ubuntu-19-10-vm-on-proxmox.70352/

sudo parted /dev/sda

resizepart 2