sudo: unable to resolve host ubuntu-server

[himayloco]

Hi All,

I am having the "sudo: unable to resolve host <hostname>" issue that some others have reported over the years. This is a fresh install of 14.04LTS that is up to date.

When I use the command

cat /etc/hostname

I get back:
<hostname>

Likewise when I use:

cat /etc/hosts

I get back:
127.0.0.1 localhost
127.0.1.1 <hostname>

# 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

I am not really sure what to try next, the hostname and hosts file both contain the same hostname....any ideas?

Cheers!

[Gone fishing]

I think you just need to give your system a host name

Open a terminal and run

sudo gedit /etc/hostname

and add something to the file for example

himayloco

then

sudo gedit /etc/hosts

amd modify it so that it looks like

127.0.0.1       localhost
127.0.1.1       himayloco

# 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

Then reboot and all should be well

[himayloco]

Hi GoneFishing, thanks for the reply!

Thats the weird thing. I do have a hostname in both places. When this problem first appeared, I had a different hostname with a capital letter in it, so I changed it to something simpler with no special characters or capitals. I used

sudo gedit /etc/hostname

to change the hostname file and

sudo gedit /etc/hosts

to change the hosts file to be that new host name. I then restarted the machine and nothing....the problem is still there.

Since you took the time to reply, and so that we can be precise, I have changed my hostname to "himayloco" for the time being. I have edited both the /etc/hostname and /etc/hosts files to reflect this hostname. I then restarted the machine and I still have the problem.

[matt_symes]

Hi

Does you hostname contain spaces or other unusual characters ?

EDIT: we were cross posting so I guess not ?

Kind regards

[matt_symes]

Hi

Can you post the output of this command.

hostname

and

grep $(hostname) /etc/hosts

Kind regards

[nerdtron]

I am having the "sudo: unable to resolve host <hostname>" issue that some others have reported over the years. This is a fresh install of 14.04LTS that is up to date.

OK. So this is the error you are getting? But the hostname and hosts file are correct already?

What terminal commands shows that error?

[himayloco]

For matt_symes:

hostname

output:
himayloco

grep $(hostname) /etc/hosts

output:
127.0.1.1 himayloco


For nerdtron:
Any terminal command that contains "sudo"

Thanks to both of you!

[nerdtron]

HHmmm this is plain weird. I remember this happening to me once and I just corrected the entry on the /etc/hosts. Yours is correct already, well, there's no typo.

Have you tried suggestions here: http://askubuntu.com/questions/59458...olve-host-none

[matt_symes]

Hi

That is odd. Can we also check your sudoers files.

boot into the recovery terminal and type

grep -nH "^[^#]" /etc/sudoers{,.d/*}

Capital H above. Maybe easier to copy and paste it into the terminal.

Kind regards

[nerdtron]

After the fresh install what else did you do? any changes on system files? What else did you install?