ssh: Could not resolve hostname (updating hostname for machine on local LAN) [closed]

Question

I have connected a raspberry pi 4 running ubuntu 20.04 to my local LAN over wifi.

From my laptop I can SSH to the raspberry just fine with:

$ ssh ubuntu@192.168.0.47
Welcome to Ubuntu 20.04.1 LTS (GNU/Linux 5.4.0-1022-raspi aarch64)

 * Documentation:  https://help.ubuntu.com
 * Management:     https://landscape.canonical.com
 * Support:        https://ubuntu.com/advantage
 ...

Instead of having to type that IP each time I would like to be able to SSH to it using the hostname: rasp01. I have found this guide:

https://thepihut.com/blogs/raspberry-pi-tutorials/19668676-renaming-your-raspberry-pi-the-hostname

that I have followed. After I have rebooted the raspberry pi and logged into it I have this:

ubuntu@rasp01:~$ hostname
rasp01

ubuntu@rasp01:~$ cat /etc/hosts

rasp01 localhost

# The following lines are desirable for IPv6 capable hosts
::1 ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
ff02::3 ip6-allhosts

ubuntu@rasp01:~$ cat /etc/hostname 
rasp01

But when I try to use that hostname when I SSH to the raspberry from my laptop on the same LAN (also running ubuntu) I get:

$ ssh ubuntu@rasp01
ssh: Could not resolve hostname rasp01: Name or service not known

$ ssh ubuntu@rasp01.local
ssh: Could not resolve hostname rasp01.local: Name or service not known

$ ssh ubuntu@rasp01.local.
ssh: Could not resolve hostname rasp01.local.: Name or service not known

What am I missing?

Answer 1

The Super User section of Stack Exchange is focused on power users. It's a good resource for SOHO networking questions such as yours. This site is for network engineering professionals, so your question is actually not on-topic here.

However, there are several ways to do what you want, among them:

• Add an entry to /etc/hosts on your workstation mapping rasp01 to 192.168.0.47
• Configure your SSH ~/.ssh/config file, adding a host entry
• Setup a DNS service for your home LAN, especially if your router supports integration with its DHCP server