It takes ~15 seconds to send single e-mail using sendmail.


Jul 31 09:52:42 piotr-probook sendmail[2912]: My unqualified host name (piotr-probook) unknown; sleeping for retry



/etc/hosts:   piotr-probook localdev localhost router


# hosts file (normally /etc/hosts)
O HostsFile=/etc/hosts

Obviously I can ping piotr-probook host and HTTP server popups in browser when i type url http://piotr-probook

What am I doing wrong? How to fix the problem?

1 Answer 1


Sendmail requires that the result of "hostname" be a fully qualified domain name to start cleanly.

Set the hostname to something like piotr-probook.localdomain and update /etc/hosts.

/etc/hosts   piotr-probook.localdomain piotr-probook localdev localhost
  • 1
    Thank you! It works! Btw. it works without changing machine hostname. I just added piotr-probook.localdomain to /etc/hosts and everything is ok
    – user21886
    Jul 31, 2013 at 13:27
  • Thanks so much, Btw, I add a newline piotr-probook.localdomain seems not work, but merge it to ONE line, it works!!
    – liuyang1
    Mar 19, 2015 at 9:33

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