Increase space Virtual Box and Linux Partition

Clone the disk

VBoxManage clonehd “path/WebServer.vmdk” “path/WebServer.vdi” –format vdi

resize 20*1024 = 20GB

VBoxManage modifyhd “path/WebServer.vdi” –resize 20480

reconvert into vmdk

VBoxManage clonehd “path/WebServer.vdi” “path/WebServer.vmdk” –format vmdk

File -> Virtual Media Manager -> Removed existing images (note, I removed them only from the registry).

1. Open the Oracle VM VirtuaBox Manager
Click on File -> Virtual Media Manager (or Ctrl+D)
2. Delete the hard disk entry in question (select and press “Del” on keyboard)
3. Open “Settings” of the Virtual Machine, go to “Storage”, click “Add Attachment”, select “Add Hard Disk” and “Choose existing disk“, then selected the vdi file and you are done.

  1. Download “gparted-live-x.xx.x-x-ixxx.iso” file from http://gparted.sourceforge.net/download.php. Mount this iso file as CD. Virtual Machine -> Settings -> Storage -> Controller IDE (Right Click) -> Add CD/DVD -> Select gparted-live-x.xx.x-x-ixxx.iso file
  2. Run virtual machine, Virtual Machine will boot from this CD. Choose default values with pressing “Enter”, “Enter” … until Gpart ISO GUI starts. Select tool gpart program and start.
  3. Extend disk size as below;
    • Right click on partitions and if “possible” click on “Disable Active Partion”.
    • Extend Partition as much as possible from GUI (for this case 500GB).
    • Right click the partition which is disabled and select “Enable Active Partion”.
    • Apply and wait until the operations finished.
    • Shut down virtual machine.
    • Unmount gparted-live-x.xx.x-x-ixxx.iso.
      $ Virtual Machine -> Settings -> Storage-> Controller IDE (Right Click on gparted-live-x.xx.x-x-ixxx.iso) -> Remove Attachement
    • Start the virtual machine.

vgdisplay

df -h

File system              Dim. Usati Dispon. Uso% Montato su
/dev/mapper/centos-root   19G  6,2G     13G  34% /
devtmpfs                 910M     0    910M   0% /dev
tmpfs                    920M     0    920M   0% /dev/shm
tmpfs                    920M  8,6M    912M   1% /run
tmpfs                    920M     0    920M   0% /sys/fs/cgroup
/dev/sda1               1014M  188M    827M  19% /boot
tmpfs                    184M     0    184M   0% /run/user/0

 

resize2fs /dev/mapper/centos-root

lvextend -l+100%FREE /dev/mapper/centos-root

resize2fs /dev/mapper/centos-root

xfs_growfs /dev/mapper/centos-root

df -ha

Steps to Perform SSH Login Without Password Using ssh-keygen & ssh-copy-id

ssh-keygen creates the public and private keys. ssh-copy-id copies the local-host’s public key to the remote-host’s authorized_keys file. ssh-copy-id also assigns proper permission to the remote-host’s home, ~/.ssh, and ~/.ssh/authorized_keys.

Step 1: Create public and private keys using ssh-key-gen on local-host

jsmith@local-host$ [Note: You are on local-host here]

jsmith@local-host$ ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/home/jsmith/.ssh/id_rsa):[Enter key]
Enter passphrase (empty for no passphrase): [Press enter key]
Enter same passphrase again: [Pess enter key]
Your identification has been saved in /home/jsmith/.ssh/id_rsa.
Your public key has been saved in /home/jsmith/.ssh/id_rsa.pub.
The key fingerprint is:
33:b3:fe:af:95:95:18:11:31:d5:de:96:2f:f2:35:f9 jsmith@local-host

Step 2: Copy the public key to remote-host using ssh-copy-id

jsmith@local-host$ ssh-copy-id -i ~/.ssh/id_rsa.pub remote-host
jsmith@remote-host's password:
Now try logging into the machine, with "ssh 'remote-host'", and check in:

.ssh/authorized_keys

to make sure we haven't added extra keys that you weren't expecting.

Note: ssh-copy-id appends the keys to the remote-host’s .ssh/authorized_key.

Step 3: Login to remote-host without entering the password

jsmith@local-host$ ssh remote-host
Last login: Sun Nov 16 17:22:33 2008 from 192.168.1.2
[Note: SSH did not ask for password.]

jsmith@remote-host$ [Note: You are on remote-host here]


The above 3 simple steps should get the job done in most cases.

How to create custom service for Centos 7

Create a script like :

[Unit]

Description = FaradCrmService

After = network.target

[Service]

ExecStart = /var/opt/jdk1.8.0_91/bin/java -jar /root/software/fia/farad-1.5.4.RELEASE.jar

[Install]

WantedBy = multi-user.target

Put the script into -> /usr/lib/systemd/system/farad.service

create a symbolic link like this : ln -s /usr/lib/systemd/system/farad.service /etc/systemd/system/multi-user.target.wants/farad.service

enable the service : systemctl enable farad.service

start the service : service farad start

if modify the script, reload it with : systemctl daemon-reload

check it status : systemctl status farad.service