configure Ubuntu to send mail (as an SMTP client using postfix)

    1. We will start with a trusty DigitalOcean instructional – at least step 1 of that instructional.
      sudo apt-get install mailutils
    2. I want to send mail using mailgun, which allows for ports 25, 587 and 465 (SSL/TLS). I’ll use 587 which is called submission in postfix terminology, I guess due to 587 being the proper port for TLS email submission. Because I want to use encryption (SASL) (or whatever), I need to setup Postfix accordingly. I changed my Postfix config file as such
       ubuntu@machine_name:~$ sudo nano /etc/postfix/
      #various stuff above
      relayhost = []:submission
      mynetworks = [::ffff:]/104 [::1]/128
      mailbox_size_limit = 20000000
      recipient_delimiter = +
      inet_interfaces = all
      inet_protocols = all
      smtp_sasl_auth_enable = yes
      smtp_tls_security_level = encrypt
      smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd

      Some of these settings are related to the DigitalOcean instructional, such as custom mailbox_size_limit. Make sure all the smtp settings are there

Continue reading “configure Ubuntu to send mail (as an SMTP client using postfix)”

Blocking websites – easily.

This is a simple instructional for blocking any domain for a whole internet connection (although you can make per computer exceptions). Basically:

  1. Create an OpenDNS account, and select domains to block.
  2. Point your internet router to OpenDNS.

So to connect to a website the first thing that happens is a DNS request, which converts a domain name into a computer readable IP address. We can use OpenDNS as our DNS server, and tell OpenDNS specific domains we want blocked (as well as domain types i.e. gambling). Continue reading “Blocking websites – easily.”