My users will only be checking mail, and I want to disable FTP access as well as shell access under CentOS Linux. How do I disable shell (SSH) and FTP access to a new or old user under Linux without deleting user account?
Q. How do I verify input data such as email address under PHP programming language?
have CentOS Linux acting as a router for our small community-based college. I see logwatch and other cron job generating emails for the root account. How do I delete those emails? I don’t want to disable email facility but just wanted to get rid of all root emails. How do I delete root user mails (mailbox) file in Linux or Unix like system?
Q. Iâ€™ve Postfix based CentOS Linux server. I need to blacklist email ID: email@example.com . How do I blacklist email address with postfix? I also have spamassassin software installed.
A. By default, the Postfix SMTP server accepts any sender address. However you can block / blacklist sender email address easily with Postfix. It has SMTP server access table.
Open /etc/postfix/sender_access file
# cd /etc/postfix
# vi sender_access
Append sender email id as follows:
Save and close the file. Use postmap command to create a database:
# postmap hash:sender_access
Now open main.cf and add code as follows:
smtpd_recipient_restrictions = check_sender_access hash:/etc/postfix/sender_access
Save and close the file. Restart / reload postfix MTA:
# /etc/init.d/postfix restart
You can also use spamassassin to blacklist email address. Just add to your own spamassassin configuration or to /etc/mail/spamassassin/local.cf file:
# vi /etc/mail/spamassassin/local.cf
Append blacklist as follows:
Save and close the file. Restart spamassassin:
# /etc/init.d/spamassassin restart
spamassassin will marke mail as SPAM instead of rejecting the same.
Q. I would like to install latest and greatest Mozilla thunderbird mail client under Linux.
How do I download and install the same to read emails?
A. Mozillaâ€™s Thunderbird 2 email application is more powerful than ever. Thunderbird 2 features many new enhancements to help you better manage your unruly inbox, and stay informed. Thunderbird 2 scales to the most sophisticated organizational needs while making it easy to find what you need. It is the best mail/news client with RSS and integrated spam filter support.
Download Thunderbird to your Linux desktop
=> Visit this site to download Thunderbird
Thunderbird 2.0 installation – Just untar file and install it
Let us say you would like to install thunderbird in your own home directory called /home/jerry/. Open X terminal and type following command.
Copy your downloaded file to /home/tom/ and untar it:
$ cp /home/tom/Desktop/thunderbird-188.8.131.52.tar.gz .
$ tar -zxvf thunderbird-184.108.40.206.tar.gz
Now software was installed. To start Thunderbird mail client, enter:
$ cd thunderbird
How do I install thunderbird for everyone?
Install thunderbird in /opt directory. Login as root user:
# cd /opt
# mkdir thunderbird
# cd thunderbird
# cp /home/tom/Desktop/thunderbird-220.127.116.11.tar.gz .
# tar -zxvf thunderbird-18.104.22.168.tar.gz
To start thunderbird, enter:
$ /opt/thunderbird/thunderbird &
How do I create thunderbird icon on my desktop?
Right click on your Linux desktop
Select Create Launcher
Fill the details as follows:
- Set name to : Thunderbird
- Set command to : /opt/thunderbird/thunderbird
- Set comment to : My Email Client
- Hit OK to create an ICON
A note about Ubuntu / Debian Linux user
If you are using Ubuntu / Debian Linux, open terminal and type the following command to install thunderbird:
$ sudo apt-get update
$ sudo apt-get install thunderbird