SSH is going to be available on Windows 10 via PowerShell. I guess no more need for Putty.
This article has instructions how to generate SSH key on the Mac. It also covers Linux and Windows. You can skip step 3 if you’re not working with Github.
Are you looking for ways to secure your Linux server? Try changing the default SSH port, normally at port 22, to something else like port 450, for example. Changing the SSH port does not necessarily make your server that more secure, but it makes it harder for people to guess which port is open for SSH use.
To change the default SSH port. Edit the /etc/ssh/sshd_config file from the Terminal.
sudo nano /etc/ssh/sshd_config
Change from Port 22 to Port 450 for example.
Save file and exit.
sudo /etc/init.d/ssh restart
To SSH to your server, all you have to do is:
ssh firstname.lastname@example.org -p 450
The Nmap utility will scan devices connected to your network. Nmap is a free open-source utility used by network admins and anyone to explore, scan, secure and audit the network. For example, if your internal network is 10.10.10.0/24 network, you can use the following Nmap options to scan your network.
nmap -sP 10.10.10.0/24
The command above produces the following output:
As you can see, the nmap utility has found 8 devices connected to my network. It usually takes 30 seconds or so to scan the entire network. With the available data, I can now ping, ssh, or view the device via web browser if that service is available. Nmap makes troubleshooting the network that much more easier.
Just like most Linux utilities, nmap has a ton of options worth checking. Simply type
-- help to read more options.
If you are a Windows user, the nmap utility is available for download.
For Ubuntu users, simply type the following to install
sudo apt-get install nmap
So you just installed the latest version of Ubuntu on your desktop. You want to access your spanking new Ubuntu machine from another computer. There are two ways in accomplishing this: (1) the fast and easy way via SSH, or (2) the slightly more difficult way via graphics called Remote Desktop.
Let’s say we go with the easy route in this article. We want to access it via SSH. I’ll follow up with another article how to access your Ubuntu desktop using Remote Desktop. So, we want to access your Ubuntu desktop via SSH. What we need is a SSH server. We can easily install OpenSSH Server by just installing the SSH server from the Terminal.
Install SSH Server
sudo apt-get install ssh-server
Your remote computer must have a SSH client to access your Ubuntu desktop. I recommend that you use Putty if you are a Windows users. Putty is a SSH client program to access your Ubuntu desktop. If you are a Mac or a Linux user, you can simply use the Terminal. Access your Ubuntu server by invoking the SSH client.
That’s the IP address of my Ubuntu desktop. You can specify a hostname if you have an internal DNS that’s working. You can also specify the username and the port number if you using a different port from the standard port 22.
ssh 10.10.10.10 -l username -p 2222
Ok, so this is the fourth time I’ve forgotten how to access my Hostgator account via SSH. I might as well document it here, for old times sake. It’s so simple really, but I don’t know why I keep on forgetting it. To access the account, just use port 2222 instead of 22. That’s it. I don’t know why I can’t remember that. I blame it on old age.
# ssh server -p 2222
Actually, I’ve been really happy with Hostgator. No major or drawn out outages. Just a couple of hiccups here and there. They are minor things, really. I counted twice, the times the site was slow, but otherwise, Hostgator was able to fix it in a couple of hours. They only thing I miss from my old webhost is the ability to install a Subversion repository on the server. Hostgator, are you listening?
But, I got that’s running now on my desktop. It’s probably better that way. It’s more secure. It’s not like my code is highly classified or super sensitive. It’s not! But, placing it on your desktop is probably better. Until your hard drive crashes. So, keep backup copies regularly.
This is a tutorial how to install a Subversion on your desktop. Subversion is an open-source revision control system. A repository is usually installed on servers so developers and programmers can have easy access to code. Subversion uses a check-in an check-out process for submitting changes to the repository. The repository can also be installed on desktop systems. Access is gained through many means by way of direct file access, ftp, http, svn and svn+ssh. See chart below.
Installing Subversion will install both Subversion administration tools and the client. In Ubuntu or Debian-based systems, you can install Subversion by performing the following commands. By the way, I added an Apache and Subversion WebDav module so both can be installed with just a single command.
sudo apt-get install subversion libapache2-svn
Reboot the Apache Web Server
sudo /etc/init.d/apache2 restart
Create a Subversion Repository
svnadmin create /home/yourname/repository/
I’m placing the repository in my home directory. You can place it anywhere in your system. You may need to use sudo if you install it outside of your home directory. Remember the repository location, we will use it a few times below to configure the Apache Subversion WebDav module, etc.
Import your Repository
svn import /path/to/import/directory file:///home/yourname/repository
If you have a repository ready, now is a good time to import it. If you are just starting out, you can initialize the Repository here.
Access to Subversion
|file://||Direct access on local disk|
|http://||Browser using http WebDav protocol|
|https://||Browser using https secure and WebDav|
|svn+ssh://||Subversion protocol and SSH tunnel|
Configure WebDav protocol
sudo vi /etc/apache2/apache2.conf
<Location /svn> DAV svn SVNPath /home/yourname/repository AuthType Basic AuthName "Repository" AuthUserFile /etc/subversion/passwd <LimitExcept GET PROPFIND OPTIONS REPORT> Require valid-user </LimitExcept> </Location>
Change Ownership to HTTP-User
sudo chown -R www-data:www-data /home/yourname/repository
Password Protect the Repository
sudo htpasswd -c /etc/subversion/passwd username
You will be asked to provide a password. Enter the password twice.
Reboot Apache Server
sudo /etc/init.d/apache2 restart
It’s probably a good idea to restart the Apache server one more time.
Next, open up your browser and access http://localhost/svn from the address bar. You will be asked for the username and password. You should see the repository and any content or directory underneath it. That’s it. Happy coding.