Linux Notes

From OpenEMR Project Wiki

General



LAMP Server



Text Editors - Command Line

vim
nano
  • Derived from pico, more features than pico, easier to use than vim.
  • Control-Y = Page Up. Control-V = Page Down.
emacs



jed
  • Menu based text editor. Yes, menus in the command line!



Mail Readers - Command Line

mail
mutt



Viewing Files

less [FILENAME]



FTP Servers

vsftp

Files
/etc/vsftpd.conf Config File
/etc/ftpusers File with a list of users that are NOT allowed FTP access
After Config Changes:      sudo etc/init.d/vsftpd restart


Configuration File Settings
local_enable=YES Allow Authentication of Users
write_enable=YES Allow Upload of Files
chroot_local_user=YES Limit users to their home directory.
chroot_list_enable=YES Limit a list of users to their home directories.
chroot_list_file=/etc/vsftpd.chroot_list Location of the list of users to limit.
ssl_enable=Yes Enable FTP over SSL (FTPS).
rsa_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem Location of SSL Certificate.
rsa_private_key_file=/etc/ssl/private/ssl-cert-snakeoil.key Location of SSL Key.



proftpd



SFTP

sftp username@192.168.1.1

Commands

pwd / lpwd Show current REMOTE directory / Show current LOCAL directory.
ls List contents of REMOTE working directory.
lls List contents of LOCAL working directory.
ls -la List contents of LOCAL working directory. List ALL, LONG FORMAT.
cd / lcd Change remote directory / Change local directory.
get remoteFile Download file from current remote directory and place in current local directory.
get remoteFile localFile Copy remote file, place it in local directory, and rename it .
get -r someDirectory Recursive command to copy entire directory.
put localFile Upload file from current LOCAL directory and place in current REMOTE directory.
bye Quit.



NFS File Server

Server

/etc/exports
  • Exports File Configuration Examples:
/ubuntu  *(ro,sync,no_root_squash)
/home    *(rw,sync,no_root_squash)
/home   192.168.1.0/255.255.255.0(rw,no_subtree_check,no_root_squash,sync,insecure)


Client

  • Package:    nfs-common
  • Create a Mount Point:   sudo mkdir -p /mnt/NFS/home
  • Mount Shared Directory:   sudo mount -t nfs -o resvport 192.168.1.1:/home /mnt/NFS/home
  • Unmount Shared Directory:  sudo umount /mnt/home



SSH Server

Configure

sudo cp /etc/ssh/sshd_config /etc/ssh/sshd_config.default
sudo chmod a-w sshd_config.default
sudo nano /etc/ssh/sshd_config
[Change:  PasswordAuthentication yes]
sudo restart ssh



Directory Structure

binEssential user command binaries.
bootStatic files of the boot loader.
cdrom
devDevice files.
etcHost-specific CONFIGURATION files, i.e. preferences.
Startup, shutdown, start, stop scripts for every individual program.
homeUser home directories.
libEssiential shared libraries and kernel modules.
mediaMount point for removable media.
mntMount point for a temporarily mounted filesystem.
optAdd-on application software packages.
procProcess information. Virtual filesystem documentation kernel and process status as text files.
rootHome directory for the root user.
run
sbinSystem binaries.
srvData for services provided by the system.
sys
usrMulti-user utilities & applications.
varVariable files. The contents of the files here is expected to grow.
Contains log, lock, spool, mail, and temp files.


Miscellaneous Commands

Enable Root User
sudo passwd root


Disable Root User
sudo passwd -dl root


Reboot
sudo reboot