Last week I got an update for Linux 18.04 and after that, I couldn't SSH into anything and I got:

ssh: Could not resolve host-name: Name or service not known

I used aliases to SSH into stuff I needed and I did not change it for weeks.

It looks like something changed with regards to my host-name but I am not sure what changed and where to look at. I checked the host-name list in etc/hosts and there is my host-name with correct IP.

Does anyone know what to do?

closed as unclear what you're asking by David Foerster, N0rbert, K7AAY, Eric Carvalho, waltinator Oct 12 '18 at 15:20

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • 1
    Hello and welcome to Ask Ubuntu! Is is just ssh which can't resolve hostnames? Can you ping an host (by name, not IP address)? – Mr Shunz Sep 25 '18 at 8:23
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    Welcome to Ask Ubuntu! Could you please edit your question to include the output of host HOSTNAME and host HOSTNAME where you replace HOSTNAME with the actual host name (not the local alias) of the SSH server? If you’re unsure what it is look at your ~/.ssh/config and/or the output of ssh -v ALIAS (where ALIAS is the host alias in question). Thanks. – David Foerster Sep 25 '18 at 8:47
  • my colleagues in the office can ssh into stuff that i can't with no problem so it must be something locally on my machine. this is output from ssh -v OpenSSH_7.6p1 Ubuntu-4, OpenSSL 1.0.2n 7 Dec 2017 debug1: Reading configuration data /home/kristijan/.ssh/config debug1: /home/kristijan/.ssh/config line 1: Applying options for * debug1: Reading configuration data /etc/ssh/ssh_config debug1: /etc/ssh/ssh_config line 19: Applying options for * ssh: Could not resolve hostname : Name or service not known – – Kristijan Grdakovic Sep 25 '18 at 15:29

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