There are few features that are not available out of the box in Ubuntu. One among such feature is SSH. If you ever install Ubuntu on your machine and expect the ssh to work by default, it doesn’t. You would get an error message that says ‘The remote system refused the connection’
And for me, being from the network background I really needed this ssh access also certain network tools as well, such as, traceroute, arp table and so on.
In this blog lets enable ssh and basic network tools in Ubuntu, eventually how to fix traceroute issue in Ubuntu.
- You must have Ubuntu machine installed with root access on your machine with internet access.
How to enable ssh access on Ubuntu ?
Step 1. Login to the terminal.
If you are using Ubuntu Desktop type CTRL+ALT+T , or right click on Desktop and click on Open in Terminal
Step 2. Install Open ssh server by entering the below commands.
sudo apt update sudo apt install openssh-server -y
Step 3. Let’s quickly check the status of ssh service that we have just installed on the machine by running the command
service ssh status.
As you can see the ssh service not only installed, it has also been started automatically.
At any point, if the ssh service has not started you can enter the command
service ssh start to start the service
Step 4. You can use ssh [email protected] address to ssh into the machine from a Linux box or use any ssh client software.
As you can see this time when I try to SSH access the Ubuntu machine, it is asking for the credentials.
And I am able to login via ssh after I entered the Ubuntu machine credentials from ssh client.
Installation of Basic network utilities in Ubuntu.
Just like SSH, if you ever try to check ARP entries by typing
arp -a, or checking the route table by typing
netstat -rn or
route -n, you get the error saying the command not found.
All these utilities are included in the net tools package, let go ahead and download and install them by typing
sudo apt install net-tools -y
After few seconds all the packages are installed successfully.
Net-tools verification in ubuntu
- When I ran the
arp -aI could see all the arp entries in the system.
- Let me run the command
route -nto see my route table
netstat -rnto see the route table
Note : By default, the ubuntu has built in tool called
ip route to check the routing table instead of route -n or netstat -rn
- IP route command would show the route differently then other utilities that we mentioned above.
Access traceroute on Ubuntu
One of the network utility that many of the network admins use in Ubuntu is the traceroute utility which would help them to see the path for a specific network.
You can install the traceroute package by running
sudo apt install inetutils-traceroute -y
Unfortunately, when you try to run the traceroute in ubuntu it would not just show the path instead it just throws some asterisk signs. Which many of the network engineers tend to believe that the network is not reachable or something is blocking the network. However that’s not the case.
The traceroute not showing the output for some reason, and there is work around for this.
Instead of using the traceroute utility I would recommend you to use MTR utility (My Traceroute ) , and it just works.
- To run MTR, type MTR and the IP that would like to trace.
- Below is the output for the tracroute I ran for the google DNS IP 22.214.171.124
And best part is MTR is installed by default in Ubuntu.