How to Configure gmail with postfix to send notices from Koha 20.5 (check in, check out and etc )

1. Installation of postfix mail server

Open a terminal and apply the following commands one by one,

sudo apt-get update

sudo apt-get install postfix

Postfix Configuration ( OK )

No Configuration ( Select and OK)

2. Copy the configuration file.

sudo cp /usr/share/postfix/main.cf.debian /etc/postfix/main.cf

3. Install following packages too

sudo apt-get install libsasl2-2
sudo apt-get install libsasl2-modules
sudo apt-get install ca-certificates

4. Open the following file and add few lines.

sudo leafpad /etc/postfix/main.cf

Add the following lines at the bottom of the file.

relayhost = [smtp.gmail.com]:587 smtp_sasl_auth_enable = yes smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd smtp_sasl_security_options = noanonymous smtp_tls_CAfile = /etc/postfix/cacert.pem smtp_use_tls = yes

5.Open the following file.

sudo leafpad /etc/postfix/sasl_passwd

Add the following line in the opened file.

[smtp.gmail.com]:587    urgmailid@gmail.com:yourpassword

Add your Gmail username and password.

6. Change the permission of the following file.

sudo chmod 400 /etc/postfix/sasl_passwd

sudo postmap /etc/postfix/sasl_passwd

sudo postalias hash:/etc/aliases

7.Create the /etc/postfix/cacert.pem. ( Ubuntu 18.04 LTS Users)

sudo cat /etc/ssl/certs/thawte_Primary_Root_CA.pem >> /etc/postfix/cacert.pem

For Ubuntu 20.04 LTS Users

sudo cat /etc/ssl/certs/Actalis_Authentication_Root_CA.pem >> /etc/postfix/cacert.pem

8.  Restart Postfix.

sudo /etc/init.d/postfix restart

9. Enable email service in Koha

sudo koha-email-enable library

10. Check the following settings in Koha to send email notices,
Koha > Administration > Patron categories > Overdue notice required > Yes

Koha Administration > Global System Preferences > Patrons > Enhancedmessagingpreferences > Allow

Information courtesy

Vimal : http://kohageek.blogspot.com/

Vinod Kumar : https://eureka.ykyuen.info/2011/02/05/postfix-relay-via-gmail/#comment-10597