Posts Tagged ‘openssl’

Apache Webserver: How to Set up multile SSL certificates on multiple domains running on one IP address with Apache SNI feature

Wednesday, September 13th, 2017


In the recent past it was impossible to add multiple different SSL .crt / .pem bundle certificates on Apache Webserver but each one of it was supposed to run under a separate domain or subdomain, preconfigured with a separate IP address, this has changed with the introduction of Apache SNI (Server Name Indication). What SNI does is it sends, the site visitor initiating connections on encrypted SSL port (443) or whatever configured a certificate that matches, the client requested server name.

Note that SNI is Apache HTTPD supported only and pitily can't be used on other services such as Mail Servers (SMTPS), (POP3S), (IMAPS) etc.
Older browsers did not have support for proper communication with WebServers supporting SNI communication, so for Websites whose aim is interoperatibility and large audience of Web clients still the preferrable way is to set up each VirtualHost under a separate IP, just like the good old days.

However Small and MidSized businesses could save some cash by not having to buy separate IPs for each Virtualhost, but just use SNI.
Besides that the people are relatively rarely using old browsers without SNI, so having clients with browsers not supporting SNI would certiainly be too rare. To recognize where a browser is having support for TLS or not is to check whether the Browser has support for TLS extension.

One requirement in order for SNI to work properly is to have registered domain because SNI works based on the requested ServerName by client.

On Debian GNU / Linux based distributions, you need to have Apache Webserver installed with enabled mod_ssl module:


linux:~# apt-get install –yes apache2

linux:~# a2enmod ssl

linux:~# /etc/init.d/apache2 restart

If you're not planning to get a trusted source certificate, especially if you're just a start-up business which is in process of testing the environment (you still did not ordered certificate via some domain registrar you might want to generate self signed certificate with openssl command and use that temporary:


linux:~# openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout /etc/apache2/ssl/ –out /etc/apache2/ssl/

Here among the prompted questions you need the a Distinguished Name or a DN.
There are quite a few fields but you can leave some blank.
For some fields leave the default value,
If you enter '.', or press enter the field will be left blank.


Country Name (2 letter code) [AU]:BG
State or Province Name (full name) [Some-State]: Sofia
Locality Name (eg, city) []:SOF
Organization Name (eg, company) [Internet Widgits Pty Ltd]:Pc-Freak.NET
Organizational Unit Name (eg, section) []:
Common Name (e.g. server FQDN or YOUR name) []                
Email Address []


(by the way it might be interesting to mention here the list of cheapest domain name registrars on the Internet as of January 2017 – source site here


Below order is given as estimated by price /  quality and provided service approximate


1. – Domains $6.95

2. NameCheap.Com – Annual fee $10.69

3. – Annual fee $8.99 for first year, $14.99$ for each additional year

4. – Annual fee $15.00

5. – Annual fee $0.99 for first year ($14.99 for each additional year)

6. Network Solutions – This was historically one of the first domain registrar companies, but the brand is pricy $34.99

7. – Not sure

8. – $9.95 (first year and $9.95 renewals)

9. – Annual fee $11.99

10. – Annual fee $9.95 first year, Renewal fee is $11.99 per year


Note that domain pricing could value depending on the type of domain name country extension and many of the domain registrars would give you discount if you purchase domain name / SSL for 2 / 3+ years.


Next step in order to use SNI is to configure the WebServer Virtualhosts file:


linux:~# vim /etc/apache2/sites-available/


# Instruct Apache to listen for connections on port 443
Listen 443
# Listen for virtual host requests on all IP addresses
NameVirtualHost *:443

# Go ahead and accept connections for these vhosts
# from non-SNI clients
SSLStrictSNIVHostCheck off

<VirtualHost *:80>
        DocumentRoot /var/www

# More directives comes here


<VirtualHost *:443>

        ServerAdmin webmaster@localhost
        DocumentRoot /var/www

        #   SSL Engine Switch:
        #   Enable/Disable SSL for this virtual host.
        SSLEngine on

        #   A self-signed (snakeoil) certificate can be created by installing
        #   the ssl-cert package. See
        #   /usr/share/doc/apache2.2-common/README.Debian.gz for more info.
        #   If both key and certificate are stored in the same file, only the
        #   SSLCertificateFile directive is needed.
        SSLCertificateFile /etc/apache2/ssl/
        SSLCertificateKeyFile /etc/apache2/ssl/

# More Apache directives could be inserted here


<VirtualHost *:443>
  DocumentRoot /var/www/sites/your-domain2

  # Other directives here


Add as many of the SNI enabled VirtualHosts following the example below, or if you prefer seperate the vhosts into separate domains.

I also recommend to check out Apache's official documentation on SNI for NameBasedSSLVhostsWithSNI etc.

Hope this article was not too boring 🙂
Enjoy life


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Converting .crt .cer .der to PEM, converting .PEM to .DER and convert .PFX PKCS#12 (.P12) to .PEM file using OpenSSL

Friday, September 1st, 2017


These commands allow you to convert certificates and keys to different formats to make them compatible with specific types of servers or software. For example, you can convert a normal PEM file that would work with Apache to a PFX (PKCS#12) file and use it with Tomcat or IIS.

  • Convert a DER file (.crt .cer .der) to PEM


    openssl x509 -inform der -in certificate.cer -out certificate.pem
  • Convert a PEM file to DER


    openssl x509 -outform der -in certificate.pem -out certificate.der
  • Convert a PKCS#12 file (.pfx .p12) containing a private key and certificates to PEM


    openssl pkcs12 -in keyStore.pfx -out keyStore.pem -nodes

    You can add -nocerts to only output the private key or add -nokeys to only output the certificates.

  • Convert a PEM certificate file and a private key to PKCS#12 (.pfx .p12)


    openssl pkcs12 -export -out certificate.pfx -inkey privateKey.key \
    -in certificate.crt -certfile CACert.crt

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MySQL SSL Configure Howto – How to Make MySQL communication secured

Wednesday, January 15th, 2014

mysql-over-ssl-how-to-configure-logo how to configure ssl on mysql server

Recently I've been asked How to make communication to MySQL database encrypted. The question was raised by a fellow developer who works on developing a Desktop standalone application in Delphi Programming Language with DevArt an (SQL Connection Component capable to connect Delphi applications to multiple databases like MySQL, Oracle, PostgreSQL, Interbase, Firebird etc.

Communicating in Secured form to MySQL database is not common task to do, as MySQL usually communicates to applications hosted on same server or applications to communicate to MySQL are in secured DMZ or administrated via phpMyAdmin web interface.

MySQL supports encrypted connections to itself using Secure Socket Layer (SSL) encryption. Setting up MySQL db to be communicated encrypted is a must for standalone Desktop applications which has to extract / insert data via remote SQL.
Configuring SQL to support communicated queries encrpytion is supported by default and easily configured on most standard Linux version distributions (Debian, RHEL, Fedora) with no need to recompile it.
1. Generate SSL Certificates

$ mkdir /etc/mysql-ssl && cd mysql-ssl

# Create CA certificate
$ openssl genrsa 2048 > ca-key.pem
$ openssl req -new -x509 -nodes -days 3600 \
         -key ca-key.pem -out ca-cert.pem

Create server certificate, remove passphrase, and sign it
server-cert.pem is public key, server-key.pem is private key
$ openssl req -newkey rsa:2048 -days 3600 \
         -nodes -keyout server-key.pem -out server-req.pem

$ openssl rsa -in server-key.pem -out server-key.pem
$ openssl x509 -req -in server-req.pem -days 3600 \
         -CA ca-cert.pem -CAkey ca-key.pem -set_serial 01 -out server-cert.pem

Create client certificate, remove passphrase, and sign it
client-cert.pem is public key and client-key.pem is private key
$ openssl req -newkey rsa:2048 -days 3600 \
         -nodes -keyout client-key.pem -out client-req.pem

$ openssl rsa -in client-key.pem -out client-key.pem
$ openssl x509 -req -in client-req.pem -days 3600 \
         -CA ca-cert.pem -CAkey ca-key.pem -set_serial 01 -out client-cert.pem

After generating the certificates, verify them:

$ openssl verify -CAfile ca-cert.pem server-cert.pem client-cert.pem

2. Add SSL support variables to my.cnf

Once SSL key pair files are generated in order to active SSL encryption support in MySQL server, add to (/etc/my.cnf,  /etc/mysql/my.cnf, /usr/local/etc/my.cnf … ) or wherever config is depending on distro


3. Restart MySQL server

/etc/init.d/mysqld restart

4. Create SQL user to require SSL login

Create new user with access to database;

GRANT ALL ON Sql_User_DB.* TO Sql_User@localhost;

To create administrator privileges user:


5. Test SSL Connection with MySQL CLI client or with few lines of PHP

To use mysql cli for testing whether SSL connection works:

$ mysql -u ssluser -p'pass' –ssl-ca /etc/mysql-ssl/client-cert.pem –ssl-cert /etc/mysql-ssl/client-key.pem

Once connected to MySQL to verify SSL connection works fine:

mysql> SHOW STATUS LIKE 'Ssl_Cipher';
| Variable_name | Value              |
| Ssl_cipher    | DHE-RSA-AES256-SHA |

If you get this output this means MySQL SSL Connection is working as should.

Alternative way is to use test-mysqli-ssl.php script to test availability to mysql over SSL.

mysqli_ssl_set($conn, '/etc/mysql-ssl/client-key.pem', '/etc/mysql-ssl/client-cert.pem', NULL, NULL, NULL);
if (!mysqli_real_connect($conn, '', 'ssluser', 'pass')) { die(); }
$res = mysqli_query($conn, 'SHOW STATUS like "Ssl_cipher"');

Note: Change username password according to your user / pass before using the script

That's all now you have mysql communicating queries data over SSL


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How to generate self signed SSL certificate with openssl on Linux / BSD

Wednesday, November 6th, 2013

How to generate self signed SSL certificate with openssl on Linux / BSD

It is common solution for personal use to generate SSL certificates which are self-signed. Self-signed certificates are dangerous as no authority or company guarantees that remote site is trustable. However for private use having encrypted connection whether you need to transfer personal data is better than not having such. There are plenty of tutorials online pointing how to set-up Apache webserver to provide access via SSL port 443 with self-signed certifacate, but anyways I decided to blog here a one-liner command way, which makes generating self-signed certificate a piece of cake. Self-signed certificates on UNIX are generated with openssl command part of openssl (Secure Socket Layer cryptocgraphic tools).

On Debian Linux to install openssl (if you still don't have it):

apt-get install --yes openssl

On Fedora, RHEL, CentOS etc. same install should be done with:

yum install -y openssl

On FreeBSD to install it use ports;

cd /usr/ports/security/openssl
make install clean

Once openssl is available, here is command to generate self signed SSL certitifacate;

openssl req -x509 -nodes -days 3650 -newkey rsa:2048 -keyout my-sitename.key -out my-sitename.crt
Generating a 2048 bit RSA private key
writing new private key to 'key.pem'
Enter PEM pass phrase:
Verifying - Enter PEM pass phrase:
You are about to be asked to enter information that will be incorporated
into your certificate request.
What you are about to enter is what is called a Distinguished Name or a DN.
There are quite a few fields but you can leave some blank
For some fields there will be a default value,
If you enter '.', the field will be left blank.
Country Name (2 letter code) [AU]:BG
State or Province Name (full name) [Some-State]:Sofia
Locality Name (eg, city) []:Sofia
Organization Name (eg, company) [Internet Widgits Pty Ltd]:Pc Freak
Organizational Unit Name (eg, section) []:Pc Freak
Common Name (eg, YOUR name) []
Email Address []

The generated certificate Private Key file is placed in my-sitename.key
, actual certificate is located in my-sitename.crt -days option tells for how long period certificate will be valid. Regenerating certificate every year (360 days) is good security practice but it is pretty annoying to see your certificate has expered thus for private self signed SSL certificate it is more confortable to generate cert for 10 years time.
To use my-sitename.key and my-sitename.crt copy them to /etc/ssl/crt/

cp -rpf my-sitename.crt /etc/ssl/crt/
cp -rpf my-sitename.key /etc/ssl/crt/

Next what's left is to configure Apache to use new generated certs. Quickest way is to add it inside virtual host. Adding to Apache also depends on Linux distribution where SSL has to be added but in general, what should work is something like:

SSLEngine on
SSLCertificateFile /etc/ssl/crt/my-sitename.crt
SSLCertificateKeyFile /etc/ssl/crt/my-sitename.key

Note that if SSL has to be enabled for specific Virtual Host you will have to place above Apache directives into the Vhost. Though certifiate will only be trusted by your authority RSA 2048 bit encryption in transfer data between your Webserver and Browser should guarantee you extra security of data, not that it is impossible for data to be still sniffed by a skilled hacker but makes data securily transferred in probably 99% of cases 🙂

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How to Prevent Server inaccessibility by using a secondary SSH Server access port

Monday, December 12th, 2011

One of the Debian servers’s SSH daemon suddenly become inaccessible today. While trying to ssh I experienced the following error:

$ ssh -v
OpenSSH_5.8p1 Debian-2, OpenSSL 0.9.8o 01 Jun 2010
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug1: Connecting to [] port 22.
debug1: Connection established.
debug1: identity file /home/hipo/.ssh/id_rsa type -1
debug1: identity file /home/hipo/.ssh/id_rsa-cert type -1
debug1: identity file /home/hipo/.ssh/id_dsa type -1
debug1: identity file /home/hipo/.ssh/id_dsa-cert type -1
Connection closed by remote host

Interestingly only the SSH server and sometimes the mail server was failing to respond and therefore any mean to access the server was lost. Anyways some of the services on the server for example Nginx continued working just fine.
Some time ago while still working for design.bgweb development company, I’ve experienced some similar errors with SSH servers, so I already had a clue, on a way to work around the issue and to secure myself against the situation to loose access to remote server because the secure shell daemon has broken up.

My work around is actually very simple, I run a secondary sshd (different sshd instance) listening on a different port number.

To do so I invoke the sshd daemon on port 2207 like so:

debian:~# /usr/sbin/sshd -p 2207

Besides that to ensure my sshd -p 2207 will be running on next boot I add:

/usr/sbin/sshd -p 2207

to /etc/rc.local (before the script end line exit 0 ). I do set the sshd -p 2207 to run via /etc/rc.local on purpose instead of directly adding a Port 2207 line in /etc/ssh/sshd_config. The reason, why I’m not using /etc/ssh/sshd_config is that I’m not sure if using the sshd config to set a secondary port does run the port under a different sshd parent. If using the config doesn’t run the separate ssh port under a different server parent this will mean that once the main parent hangs, the secondary port will become inaccessible as well.

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How to encrypt files with GPG and OpenSSL on GNU / Linux

Friday, November 25th, 2011

Encrypt files and directories with OpenSSL and GPG (GNUPG), OpenSSL and GPG encryption logo

I have just recently found out that it is possible to use openssl to encrypt files to tighten your security.
Why would I want to encrypt files? Well very simple, I have plain text files where I write down my passwords for servers or account logins for services I use on the internet.

Before this very day I use gpg to encrypt and decrypt my sensitive information files and archives. The way to encrypt files with GPG is very simple, here is an example:

server:~# ls -al test.txt
-rw-r--r-- 1 root root 12 Nov 25 16:50 test.txt
server:~# gpg -c test.txt > test.txt.gpg
Enter passphrase:
Repeat passphrase:

Typing twice the same password produces the encrypted file test.txt.gpg . In order to later decrypt the gpg password protected file I use cmd:

server:~# gpg -d test.txt.gpg >test.txt
Enter passphrase:
Repeat passphrase:
gpg: CAST5 encrypted data
gpg: encrypted with 1 passphrase
gpg: WARNING: message was not integrity protected

As one can see from above output by default gpg uses the CAST5 algorithm to encrypt the data. For all those curious on what kind of encryption does CAST5 provide and where the CAST5 origins are, in short CAST5 is a GNU invented cryptographic algorithm, the short description of the algorithm is as follows:

“…a DES-like Substitution-Permutation Network (SPN) cryptosystem which appears to have good resistance to differential cryptanalysis, linear cryptanalysis, and related-key cryptanalysis. This cipher also possesses a number of other desirable cryptographic properties, including avalanche, Strict Avalanche Criterion (SAC), Bit Independence Criterion (BIC), no complementation property, and an absence of weak and semi-weak keys.”

Anyways, for all those who trust more the DES128 encryption as an encryption algorithm to keep your data secret, the openssl command tool provides another mean to encrypt sensitive data.
To encrypt a file using the openssl’s DES encryption capabilities:

server:~# openssl des -salt -in test.txt -out test.txt.des
enter des-cbc encryption password:
Verifying - enter des-cbc encryption password:

As you can see to encrypt with the DES-CBC its necessery to type twice the secret password “salt” keyword which will be used as an encryption key.

To decrypt later on the DES encrypted file the cmd is:

server:~# openssl des -d -salt -in file.des -out file

In order to encrypt a whole directory earlier compressed with tar zip:

server:~# tar -czf - directory | openssl des -salt -out directory.tar.gz.des

Where directory is the name of directory which will be tarred and crypted.

To later decrypt with openssl the above encrypted tar.gz.des file:

server:~# openssl des -d -salt -in directory.tar.gzdes | tar -x

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How to renew self signed QMAIL toaster and QMAIL rocks expired SSL pem certificate

Friday, September 2nd, 2011


One of the QMAIL server installs, I have installed very long time ago. I've been notified by clients, that the certificate of the mail server has expired and therefore I had to quickly renew the certificate.

This qmail installation, SSL certificates were located in /var/qmail/control under the names servercert.key and cervercert.pem

Renewing the certificates with a new self signed ones is pretty straight forward, to renew them I had to issue the following commands:

1. Generate servercert encoded key with 1024 bit encoding

debian:~# cd /var/qmail/control
debian:/var/qmail/control# openssl genrsa -des3 -out servercert.key.enc 1024
Generating RSA private key, 1024 bit long modulus
e is 65537 (0x10001)
Enter pass phrase for servercert.key.enc:
Verifying - Enter pass phrase for servercert.key.enc:

In the Enter pass phrase for servercert.key.enc I typed twice my encoded key password, any password is good, here though using a stronger one is better.

2. Generate the servercert.key file

debian:/var/qmail/control# openssl rsa -in servercert.key.enc -out servercert.key
Enter pass phrase for servercert.key.enc:
writing RSA key

3. Generate the certificate request

debian:/var/qmail/control# openssl req -new -key servercert.key -out servercert.csr
debian:/var/qmail/control# openssl rsa -in servercert.key.enc -out servercert.key
Enter pass phrase for servercert.key.enc:writing RSA key
root@soccerfame:/var/qmail/control# openssl req -new -key servercert.key -out servercert.csr
You are about to be asked to enter information that will be incorporated
into your certificate request.
What you are about to enter is what is called a Distinguished Name or a DN.
There are quite a few fields but you can leave some blank
For some fields there will be a default value,
If you enter '.', the field will be left blank.
Country Name (2 letter code) [AU]:UK
State or Province Name (full name) [Some-State]:London
Locality Name (eg, city) []:London
Organization Name (eg, company) [Internet Widgits Pty Ltd]:My Company
Organizational Unit Name (eg, section) []:My Org
Common Name (eg, YOUR name) []:
Email Address []

Please enter the following 'extra' attributes
to be sent with your certificate request
A challenge password []:
An optional company name []:

In the above prompts its necessery to fill in the company name and location, as each of the prompts clearly states.

4. Sign the just generated certificate request

debian:/var/qmail/control# openssl x509 -req -days 9999 -in servercert.csr -signkey servercert.key -out servercert.crt

Notice the option -days 9999 this option instructs the newly generated self signed certificate to be valid for 9999 days which is quite a long time, the reason why the previous generated self signed certificate expired was that it was built for only 365 days

5. Fix the newly generated servercert.pem permissions debian:~# cd /var/qmail/control
debian:/var/qmail/control# chmod 640 servercert.pem
debian:/var/qmail/control# chown vpopmail:vchkpw servercert.pem
debian:/var/qmail/control# cp -f servercert.pem clientcert.pem
debian:/var/qmail/control# chown root:qmail clientcert.pem
debian:/var/qmail/control# chmod 640 clientcert.pem

Finally to load the new certificate, restart of qmail is required:

6. Restart qmail server

debian:/var/qmail/control# qmailctl restart
Restarting qmail:
* Stopping qmail-smtpd.
* Sending qmail-send SIGTERM and restarting.
* Restarting qmail-smtpd.

Test the newly installed certificate

To test the newly installed SSL certificate use the following commands:

debian:~# openssl s_client -crlf -connect localhost:465 -quiet
depth=0 /C=UK/ST=London/L=London/O=My Org/OU=My Company/
verify error:num=18:self signed certificate
verify return:1
debian:~# openssl s_client -starttls smtp -crlf -connect localhost:25 -quiet
depth=0 /C=UK/ST=London/L=London/O=My Org/OU=My Company/
verify error:num=18:self signed certificate
verify return:1

If an error is returned like 32943:error:140770FC:SSL routines:SSL23_GET_SERVER_HELLO:unknown protocol:s23_clnt.c:607: this means that SSL variable in the qmail-smtpdssl/run script is set to 0.

To solve this error, change SSL=0 to SSL=1 in /var/qmail/supervise/qmail-smtpdssl/run and do qmailctl restart

The error verify return:1 displayed is perfectly fine and it's more of a warning than an error as it just reports the certificate is self signed.

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How to check if newly installed SSL certificate for IMAP and IMAPS is properly installed

Tuesday, June 28th, 2011

Did you have to regenerate your SSL certificate for your mail server’s IMAP and IMAP SSL service?
Did you have to find out if the newly installed certificates are fine after install?

Here is how:

          root@server-hosting [/usr/local ]# openssl s_client -connect
root@server-hosting [/usr/local ]# openssl s_client -connect -starttls imap

The output returned by this two commands will be the imap and imaps configured certificates as well as extensive info concerning the installed SSL, the last chunk of info to be spit is most crucial to know if certificate is fine.
It should be something like:

New, TLSv1/SSLv3, Cipher is AES256-SHA
Server public key is 1024 bit
Secure Renegotiation IS supported
Compression: NONE
Expansion: NONE
Protocol : TLSv1
Cipher : AES256-SHA
Session-ID: 0B69E91022CB56D64F56CFA08405944D9C4C0069EE4097890B98F1406CF084D5
Master-Key: 13745B94E0C5A0604EB7529E7409251961DFD5F4134F3A8F
Key-Arg : None
Start Time: 1309265383
Timeout : 300 (sec)
Verify return code: 18 (self signed certificate)
. OK CAPABILITY completed

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Auto insert password for a Trusted SSL Certificate / Automatically enter password for an SSL Certificate during Apache startup on Debian Lenny

Friday, March 26th, 2010

I've recently installed a Trusted certificate that I've previously protected with a pass-phrase to an Apache server running on top of Debian in order to have a better security.
Now everytime I restart Apache it's pretty annyoing and non-practical at the same time, to enter the Passphrase assigned to the SSL certificate.
It's also dangerous because if Apache crashes and tries to resurrect itself restartig it might not start-up again.
Another unpleasant possible scenario is if for example some of the php code developers tries to change something minor in some Virtualhost and afterwards restarts Apache for the new configurations to take place, again Apache won't bring up and a chaos would emerge.
So I decided to configurate my Apache that it auto fills in the passphrase each time it's being started or restarted.To do that I consulted some online resources and I end up redirected by a blog post to the mod_ssl ssl_reference web page

There is plenty of stuff on that document however in my case all I needed was one directive in /etc/apache2/mods-avalable/mods-available/ssl.conf :

SSLPassPhraseDialog exec:/etc/apache2/mods-available/passphrase

The above code must replace:

SSLPassPhraseDialog builtin

Now last step is to prepare the /etc/apache2/mods-available/passphrase .
Make sure the file has the following content:

echo "yoursecretpassword"

Change above yoursecretpassword with your configured passphrase.
Also please make sure /etc/apache2/mods-availabe/passphrase has proper set permissions. In my case I've set the following permissions for the file:

debian:~# chown www-data:www-data /etc/apache2/mods-available/passphrase
debian:~# chmod 700 /etc/apache2/mods-available/passphrase

That should be it, Restart Apache and make sure Apache is properly loaded without anySSL passphrase prompts.
However you should have in mind that auto enabling passphrase loading on starting in Apache is much more insecure than typing in the password every time you restart Apache. Storing the passphrase in a file is quite insecure compared to if you type it every time Apache starts.
For instance if a hacker breaks into your server he might be able to steal your SSL certificate as well as the passphrase file.
And surely this is something you don't want. Anyways flexibility has a price and if you decide to go the way described, please note the risk first.



If you haven't already added a password to your private key during certficate generation time,

Of course you can add/remove a passphrase at a later time.

    add one (assuming it was an rsa key, else use dsa)

    openssl rsa -des3 -in your.key -out your.encrypted.key
    mv your.encrypted.key your.key

    the -des3 tells openssl to encrypt the key with DES3.

    remove it

    openssl rsa -in your.key -out

    you will be asked for your passphrase one last time
    by omitting the -des3 you tell openssl to not encrypt the output.

    mv your.key


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