Ttgjyuk

I need some help with this please.

I started here as mentioned: in this post This post

nitapika@nitapika-51:~$ echo bla | mail -s testmail lisa@you5.com

The program 'mail' is currently not installed. You can install it by typing:
sudo apt-get install mailutils

Then installed mailutils: and received this error

Running newaliases
newaliases: warning: valid_hostname: numeric hostname: 04
newaliases: fatal: file /etc/postfix/main.cf: parameter mydomain: bad parameter value: 04
dpkg: error processing package postfix (--configure):
 subprocess installed post-installation script returned error exit status 75
dpkg: dependency problems prevent configuration of mailutils:
 mailutils depends on default-mta | mail-transport-agent; however:
 Package default-mta is not installed.
 Package postfix which provides default-mta is not configured yet.
 Package mail-transport-agent is not installed.
 Package postfix which provides mail-transport-agent is not configured yet.

dpkg: error processing package mailutils (--configure):
 dependency problems - leaving unconfigured
Processing triggers for libc-bin (2.21-0ubuntu4) ...No apport report written because the error message indicates its a followup error from a previous failure.

Errors were encountered while processing:
 postfix
 mailutils
E: Sub-process /usr/bin/dpkg returned an error code (1)

nitapika@nitapika-51:~$ sudo /etc/init.d/postfix reload

[....] Reloading postfix configuration (via systemctl): postfix.serviceJob for postfix.service invalid.
 failed!

Then tried:

nitapika@nitapika-51:~$ sudo apt-get -f install 

Reading package lists... Done
Building dependency tree 
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.
2 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Setting up postfix (2.11.3-1ubuntu2) ...

Postfix configuration was not changed. If you need to make changes, edit
/etc/postfix/main.cf (and others) as needed. To view Postfix configuration
values, see postconf(1).

After modifying main.cf, be sure to run '/etc/init.d/postfix reload'.

Running newaliases
newaliases: warning: valid_hostname: numeric hostname: 04
newaliases: fatal: file /etc/postfix/main.cf: parameter mydomain: bad parameter value: 04
dpkg: error processing package postfix (--configure):
 subprocess installed post-installation script returned error exit status 75
dpkg: dependency problems prevent configuration of mailutils:
 mailutils depends on default-mta | mail-transport-agent; however:
 Package default-mta is not installed.
 Package postfix which provides default-mta is not configured yet.
 Package mail-transport-agent is not installed.
 Package postfix which provides mail-transport-agent is not configured yet.

dpkg: error processing package mailutils (--configure):
 dependency problems - leaving unconfigured
Processing triggers for libc-bin (2.21-0ubuntu4) ...No apport report written because the error message indicates its a followup error from a previous failure.

Errors were encountered while processing:
 postfix
 mailutils
E: Sub-process /usr/bin/dpkg returned an error code (1)

And then:

nitapika@nitapika-51:~$ sudo dpkg-reconfigure -plow postfix
/usr/sbin/dpkg-reconfigure: postfix is broken or not fully installed

Not sure how to fix this. I only need the logcheck app to send me abnormalities.

1. 
   

   Correct mydomain in /etc/postfix/main.cf.

   
   
   

   04 is not a valid domain name - a valid value is an entry of the tour domain.tld.

   
   


2. 
   

   Change the value for valid_hostname as well.

   
   
   

   This is only a warning but hostnames are not numeric - use the output of

   
   
   

   hostname --fqdn
   

   
   

After that execute:

sudo newaliases
sudo apt-get install -f

mydomain

 The internet domain name of this mail system. The default is to use
 $myhostname minus the first component, or "localdomain" (Postfix 2.3 
 and later). $mydomain is used as a default value for many other
 configuration parameters.

myhostname

 The internet hostname of this mail system. The default is to use the
 fully-qualified domain name (FQDN) from gethostname(), or to use the
 non-FQDN result from gethostname() and append ".$mydomain".$myhostname
 is used as a default value for many other configuration parameters.

first know your hostname using command : hostname

just edit /etc/postfix/main.cf

use:
sudo nano /etc/postfix/main.cf

change: myhostname =

to

myhostname = your_hostname (name of your hostname)

now logout the system and re-login

now run :

sudo apt install -f