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enable ssl for postfix in sentora

Like dovecot, sentora does not enable ssl for postfix by default, either. How do you know if ssl is enabled? You can use the command “netstat -antp|grep master”. master is the daemon of postfix. You’ll see postfix uses the port

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How to enable SSL for Dovecot in Sentora?

As always, Sentora does not care about security and SSL stuff for its users. So by default, dovecot provided by Sentora listens on port 110(POP) and port 143(IMAP) and the communication thru the ports is not encrypted. We have learned

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difference bewteen memcache and memcached

The daemon(server) of the memcache system is called memcached. You can install the memcache server using “yum install memcached”. There are two php memcache extensions: memcache and memcached, both can work for the same memcache server mentioned before. memcache  is

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fix a dns problem

Today I encountered a problem when installing python-setuptools with yum. yum install python-setuptools The above command runs for a long time then shows the following error: yum install python-setuptools Loaded plugins: fastestmirror Determining fastest mirrors Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=6&arch=x86_64&repo=os

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Helo command rejected: need fully-qualified hostname

I got this error when I tried to send an email to a local user  using outlook express, and as an unauthorized person. If I check the option “my server needs authentication” on, and input the correct account information that

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How to debug Postfix?

If you’ve read about my tutorial on setting up Postfix, you should be able to send and receive emails now. But life never goes smooth always.  You may encounter this or that problem in using the email system. To solve

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A strange reason that causes httpd dead

Today, my website is down.

This problem persists even I restart httpd. I have to look into the apache log to investigate what happened. Where is the apache log? I know the location of the error/access log for the

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generate certification using openssl

Certification is frequently used in secure communication such as https and smtps. Certification contains the subject information and its public key, and a signature. The signature is generated by encrypting the hash of   the subject information and its public

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How to use openssl to send emails?

Sure, you can use an email client such as outlook to send emails, but openssl can help you debug the problems when you set up/configure your own email system. After issuing the following command,

  You can see the

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How to install and configure Postfix on CentOS?

I like digitalocean’s tutorials about setting up servers and VPS, which is usually easy to understand, and if not (like this Postfix tutorial), at least works! I composed a tutorial about setting up sendmail. In that tutorial, you can see

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