SSH eror denied public key

The issue is within your sshd_config file.

Here is the ULTIMATE solution to this issue:

1. Log as root to your Ubuntu server
2. Use vim or nano to edit the contents of /etc/ssh/sshd_config
   Eg. vi /etc/ssh/sshd_config or nano /etc/ssh/sshd_config
3. Now go to the very bottom of the file (to the line with PasswordAuthentication) - Change the value next to PasswordAuthentication from no to yes. 
   It should now look like this:

   # Change to no to disable tunnelled clear text passwords
   PasswordAuthentication yes
   

4. Save the file and then run the following command to reload the SSH config:
   sudo service sshd reload

With this done, you can now set up your new SSH key for your LOCAL device.
To do this, you can run the following from your LOCAL device, not the server:

ssh-copy-id username@droplet.ip

(Make sure to replace username with your username on the droplet and droplet.ip with the full IP address of your droplet)

Ifconfig Tidak ada di Debian terbaru, Begini solusinya

Call me old fashioned, but I still prefer using ifconfig command. It's not as cool as the ip command found in recent Linux distros, but familiar and universal enough to be found pretty much everywhere else. This post shows how to install packages to make ifconfig working again.

/sbin/ifconfig: no such file or directory

Yep, that's the error message I'm seeing on most recent distros. This simply means that ifconfig is no longer a core functionality installed with a base OS. You can still get it by installing net-tools package in your environment.

Here's how my attempt looked on Debian 9 (Stretch) VM just a few minutes ago:

greys@debian9:~$ ifconfig -a
-su: /sbin/ifconfig: No such file or directory

Install net-tools package for ifconfig and more

Simple enough step (I just know and remember that ifconfig is in net-tools package):

You need to have superuser powers, and by default Debian 9 doesn't have sudo installed – so I'm just using su command to become root:

greys@debian9:~$ su -
Password:

And now we install the net-tools package:

root@debian9:~# apt install net-tools
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
net-tools
0 upgraded, 1 newly installed, 0 to remove and 154 not upgraded.
Need to get 248 kB of archives.
After this operation, 963 kB of additional disk space will be used.
Get:1 http://ftp.ie.debian.org/debian stretch/main amd64 net-tools amd64 1.60+git20161116.90da8a0-1 [248 kB]
Fetched 248 kB in 0s (601 kB/s)
Selecting previously unselected package net-tools.
(Reading database ... 128276 files and directories currently installed.)
Preparing to unpack .../net-tools_1.60+git20161116.90da8a0-1_amd64.deb ...
Unpacking net-tools (1.60+git20161116.90da8a0-1) ...
Processing triggers for man-db (2.7.6.1-2) ...
Setting up net-tools (1.60+git20161116.90da8a0-1) ...

That's it, ifconfig should start working right away:

root@debian9:~# ifconfig -a
enp0s3: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.X.Y netmask 255.255.255.0 broadcast 192.168.1.255
inet6 fe80::a00:27ff:febe:8a41 prefixlen 64 scopeid 0x20<link>
ether 08:00:27:be:8a:41 txqueuelen 1000 (Ethernet)
RX packets 94337 bytes 138887593 (132.4 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 31380 bytes 2338487 (2.2 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1 (Local Loopback)
RX packets 1154 bytes 292002 (285.1 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 1154 bytes 292002 (285.1 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

Cara Install PosgreSQL di Debian

PostgreSQL is an open source object-relational database system. It is one of leading database server used for production servers. This tutorial will help you to install the PostgreSQL database server on Debian 8 Jessie systems.

Step 1 – Prerequsities

First, you need to import PostgreSQL packages signing key on your system. Use the below command to import the key.

wget -q https://www.postgresql.org/media/keys/ACCC4CF8.asc -O - | sudo apt-key add -

Now add PostgreSQL apt repository in your system as per your operating system. These are suggested on official PostgreSQL website using following command.

sudo sh -c 'echo "deb http://apt.postgresql.org/pub/repos/apt/ jessie-pgdg main" >> /etc/apt/sources.list.d/pgdg.list'

Step 2 – Install PostgreSQL on Debian 8

At this stage, you have successfully added PostgreSQL official repository in your system. Now update the repository list. After that install Latest PostgreSQL Server in our Ubuntu system using following commands.

sudo apt-get update
sudo apt-get install postgresql postgresql-contrib

Step 3 – Connect to PostgreSQL

After installing the PostgreSQL database server by default, it creates a user ‘postgres’ with role ‘postgres’. It also creates a system account with the same name ‘postgres’. So to connect to postgres server, login to your system as user postgres and connect database.

sudo su - postgres
psql

Now you are logged in to PostgreSQL database server. To check login info use following command from database command prompt.

postgres-# \conninfo

To disconnect from PostgreSQL database command prompt just type below command and press enter. It will return you back to Debian command prompt.

postgres-# \q

Your PostgreSQL installation has been completed successfully. 

Cara Install Guest Addition Virtual Box untuk Debian

How to Install Virtualbox Guest Additions on Debian Step by Step

In this tutorial I will show you how to install virtualbox guest additions on Debian virtual machine. Guest additions allow your guest OS to be full screen. So you can use the guest OS just like you are using a normal OS. I am using elmentary OS as the host OS, but the following method works for any host OS.

Tip: Guest additions are to be installed inside a guest OS.

Install Virtualbox Guest Additions on Debian

Log into Debian (Guest OS) as root and update your software.

apt-get update && apt-get upgrade

Install required packages for building kernel modules.

apt-get install build-essential module-assistant

Prepare your system for building kernel module

m-a prepare

In the virtual machine window, select Devices > Insert Guest Additions CD image.

It will ask you to download the guest additions iso image. Click Download.


If you can’t download it from the above window, then go to http://download.virtualbox.org/virtualbox/. Select a version and download VBoxGuestAdditions iso to your home directory.
Once downloaded, insert the iso image. If you see the following error, click force umount.

In Debian terminal, run

mount /media/cdrom

Under /media/cdrom directory there’s a shell script named VboxLinuxAdditions.run. Run this script.

sh /media/cdrom/VBoxLinuxAdditions.run

Outputs

Verifying archive integrity... All good.
Uncompressing VirtualBox 4.3.34 Guest Additions for Linux............
VirtualBox Guest Additions installer
Copying additional installer modules ...
Installing additional modules ...
Removing existing VirtualBox DKMS kernel modules ...done.
Removing existing VirtualBox non-DKMS kernel modules ...done.
Building the VirtualBox Guest Additions kernel modules ...done.
Doing non-kernel setup of the Guest Additions ...done.
You should restart your guest to make sure the new modules are actually used

Installing the Window System drivers
Installing X.Org Server 1.16 modules ...done.
Setting up the Window System to use the Guest Additions ...done.
You may need to restart the the Window System (or just restart the guest system)
to enable the Guest Additions.

Installing graphics libraries and desktop services components ...done.

Note that building kernel module must be successful. Now restart your virtual machine. You should be able to enter full screen mode by pressing Right Ctrl + F.

ACTIVE DIRECTORY, USER MANAGEMENT AND REMOTE INSTALLATION SERVICE (RIS)

pada kesempatan kali ini kita akan membahas secara ringkas tentang cara konfigurasi DHCP Server pada windows server 2003.

oke mari kita bahas, setelah pesan-pesan berikut.

DHCP (Dynamic Configuration Protocol) adalah layanan yang secara otomatis memberikan nomor IP kepada komputer yang memintanya. Komputer yang memberikan nomor IP disebut sebagai DHCP server, sedangkan komputer yang meminta nomor IP disebut sebagai DHCP Client.

Dengan demikian administrator tidak perlu lagi harus memberikan nomor IP secara manual pada saat konfigurasi TCP/IP, tapi cukup dengan memberikan referensi kepada DHCP Server.

Pada saat kedua DHCP client dihidupkan, maka komputer tersebut melakukan request ke DHCP-Server untuk mendapatkan nomor IP. DHCP menjawab dengan memberikan nomor IP yang ada di database DHCP.

DHCP Server setelah memberikan nomor IP, maka server meminjamkan (lease) nomor IP yang ada ke DHCP-Client dan mencoret nomor IP tersebut dari daftar pool. Nomor IP diberikan bersama dengan subnet mask dan default gateway. Jika tidak ada lagi nomor IP yang dapat diberikan, maka client tidak dapat menginisialisasi TCP/IP, dengan sendirinya tidak dapat tersambung pada jaringan tersebut.

Mohon perhatikan dengan benar dan teliti agar proses konfigurasi berjalan dengan lancar.

·       Buka Program Aplikasi VirtualBox

·       Dan jalankan Windows Server 2003nya