Archive for the ‘linux’ Category

Install, configure and run SVN server on Linux

This note is about how to install, configure and run SVN (Subversion) server on Linux. In my case, it’s Debian.

The requirements:

  • Use svnserve, so access repositories via svn:// protocol.
  • Install, configure and run SVN server as fast as possible.

Install SVN (Subversion) server

    sudo apt-get install subversion

Create the folder for repositories

In this example repositories are located in /var/spool/svn/, you may choose the another folder.

    sudo mkdir /var/spool/svn

Create the first repository

In the code below, the new repository is created in the test folder.

    sudo svnadmin create /var/spool/svn/test

Configure access

Find /var/spool/svn/test/conf/svnserve.conf and check that password-db, anon-access and auth-access are uncommented and have the following values:

    password-db = passwd
    anon-access = none
    auth-access = write

Set users passwords in repository’s passwd file:

    [users]
    user1 = passwordforuser1
    user2 = passwordforuser2
    user3 = passwordforuser3

Start SVN server with help of svnserve

    svnserve -d -r /var/spool/svn

Possible problems:

1. If you cannot checkout and get the error, use the correct path.

    user@server:~$ svn co svn://server.url/var/spool/svn/test ~/test

svn: No repository found in ‘svn://server.url/var/spool/svn/test’

Incorrect repository path. It should be:

    user@server:~$ svn co svn://server.url/test ~/test

2. If you get an access error check the repository access configuration.

    user@server:~$ svn co svn://server.url/test ~/test --username user1 --password 123456

svn: No access allowed to this repository

No access to this repository. Check that password-db is uncommented in svnserve.conf and auth-access has the value of write:

    password-db = passwd
    auth-access = write

Also check that you have the user password configuration in passwd file of the repository.

Remote backup and restore SVN repository

Backup:

    sudo svnrdump http://some.url/some-repository > backup.dump

Restore:

    sudo svnadmin load repository_name < ~/backup.dump

Useful links

Subversion

Setting Up an Ubuntu Subversion Server

Configure DKIM on Postfix

Here are steps to configure DKIM on Postfix.

I configure DKIM on Postfix using the Ubuntu.

1. Install dkim

sudo apt-get update
sudo apt-get upgrade
sudo apt-get install opendkim opendkim-tools

2. Configure /etc/opendkim.conf

Domain              yourdomain.com
KeyFile             /etc/mail/mail.private
Selector            mail

3. Configure /etc/default/opendkim file

Add to the end of the file.

SOCKET="inet:8891"

4. Configure /etc/postfix/main.cf file

Add these configuration options to the end of the main.cf file.

# DKIM
milter_default_action = accept
milter_protocol = 2
smtpd_milters = inet:localhost:8891
non_smtpd_milters = inet:localhost:8891

5. Create directory /etc/mail and go there with cd

6. Generate keys in /etc/mail

sudo opendkim-genkey -t -s mail -d youdomain.com

After generating keys you’ll have mail.private and mail.txt in the directory. mail.private is your private key and mail.txt is the public key that you should set as TXT record of the domain.

7. Configure your domain TXT record for DKIM

mail.txt contains what you should set for the domain. It contains something like this:

mail._domainkey IN TXT "v=DKIM1; k=rsa; t=y; p=MIG...QAB" ; 
----- DKIM key mail for youdomain.com

This means that you need to create TXT record for you domain that has mail._domainkey as a “host name” and v=DKIM1; k=rsa; t=y; p=MI…AQAB as a “ip address/url”.

7. Start opendkim and restart Postfix

sudo service opendkim start
sudo service postfix restart

8. Useful links

help.ubuntu.com/community/Postfix/DKIM

Short ssh alias to access to remote host via ssh

Often, when I want to access my remote DigitalOcean server I have to find out the IP address of it. It isn’t comfortable for me so I decided to create a short alias for this IP in /etc/hosts. Now, after I’ve just made an alias, it’s really more comfortable and faster to login to the remove server via ssh.

/ets/hosts

   localhost
       infous-desktop
    your_alias

Login via ssh using the alias

ssh 

UPDATE:

The another way to set the ssh alias is to edit the ~/.ssh/config file.

Host your_alias
Hostname 

Then to login just type:

ssh 

But there’s a shorter way. Again, edit ~/.ssh/config and set:

Host your_alias
Hostname 
User your_user

Now, you can login to your remote host via ssh like:

ssh your_alias

Thanks to everybody that commented this little note and suggested more elegant solutions!

Install PhpStorm on Ubuntu

I use Ubuntu 11.10 and in this short note I will provide steps to install PhpStorm.

1. Install Java

  sudo add-apt-repository ppa:webupd8team/java
  sudo apt-get update
  sudo apt-get install oracle-java7-installer

And check that Java’s been installed well:

  java -version

Or:

  javac -version

http://www.webupd8.org/2012/01/install-oracle-java-jdk-7-in-ubuntu-via.html

2. Download PhpStorm for Linux. You will download PhpStorm-5.0.4.tar.gz or something like this. BTW, I download it using Google Chrome.

http://wiki.jetbrains.net/intellij/Installing_and_running_PHPStorm_on_Ubuntu

3. Click on the downloaded archive so that Archive Manager will be opened. Extract all files to ~/PhpStorm/ if you don’t have this folder create it.

Screenshot at 2013-03-02 13:09:01

Screenshot at 2013-03-02 13:11:13

Don’t uncheck “Re-create folders” and “Overwrite existing files”. Everything should be like on the screenshots above. Otherwise the folder structure will be broken and you might get the error, when you’re launching phpstorm.sh:

Error: Could not find or load main class com.intellij.idea.Main

4. After the PhpStorm archive has been extracted quit the Archive Manager.

5. Open the Terminal and find phpstorm.sh inside ~/PhpStorm/PhpStorm-121.390/bin/ folder and run it:

  sudo ~/PhpStorm/PhpStorm-121.390/bin/phpstorm.sh

Congratulations, PhpStorm should be installed and launched!

Configure Postfix only to send mail

Very often you need to send mail only. For example, your web site sends some notifications by email only. In this case, there’s a reason to configure you MTA (main transfer agent) only to send emails.

In case of Postfix, only some options should be edited to force your Postfix to send mail only.

/etc/postfix/main.cf

inet_interfaces = loopback-only
mydestination =

Comment existing inet_interfaces and mydestination if they’re exist by using # at the beginning of the line.

Don’t forget to reload Postfix:

  sudo /etc/init.d/postfix reload

For more information you may read Postfix on a null client.

How to install Postfix on Ubuntu

Here’s a quick guide of installing Postfix (Mail Transfer Agent) on Ubuntu Linux.

To install Postfix type this command:

  sudo apt-get install postfix

/etc/postfix/main.cf is a main configuration file.

At least, configure a hostname in main.cf.

To find out the value of some configuration option type this command, for example, find out the myhostname value:

  postconf -d myhostname

After all the changes have been made to main.cf you should restart the Postfix to apply the changes:

  sudo /etc/init.d/postfix reload

sendmail command examples

Before all of the things you need Linux and something like Postfix installed. I test these examples on Ubuntu.

In the first example, we will create a file with the message and then we’ll send it to the recipient with help of sendmail command.

Create the file /tmp/mail.txt that contains the text and a new line at the end:

  sudo nano /tmp/mail.txt
Subject: the subject
This is the text of the message.
[new line]

Then type this:

  sendmail recipient@gmail.com < /tmp/mail.txt

GD extension required

I’ve tryed to use some GD functions in php. Locally everything is ok, I use xampp on Windows. But when I moved my site to the server I get this error:

PHP Fatal error: Uncaught exception ‘WideImage_Exception’ with message ‘WideImage requires the GD extension, but it’s apparently not loaded…

In my php app the WideImage library is used and it utilizes GD library. So, there isn’t GD extension installed. Well, let’s install it:

apt-get update
apt-get upgrade --show-upgraded
apt-get install php5-gd

After installing php5 gd library the error have been gone and WideImage classes begin to work properly.

PHP has lots of libraries and modules. To list them you can use this command:

apt-cache search php5-

Then you will see:

php5-cgi - server-side, HTML-embedded scripting language (CGI binary)
php5-cli - command-line interpreter for the php5 scripting language
php5-common - Common files for packages built from the php5 source
php5-curl - CURL module for php5
php5-dbg - Debug symbols for PHP5
php5-dev - Files for PHP5 module development
php5-gd - GD module for php5
php5-gmp - GMP module for php5
php5-ldap - LDAP module for php5
php5-mysql - MySQL module for php5
[...]

If you want to install a module run the command:

sudo apt-get install module-or-library-name

It’s possible to install several modules or libraries at once just separate them with a space.

Cron timezone problem

I’ve just tried to understand what’s the problem with my crontab. I set it to a proper time but nothing happens. As i guessed the problem is in timezone.

I use Debian linux so here I’ll provide steps how I’ve fixed it:

Configure time zone with dpkg-reconfigure
    dpkg-reconfigure tzdata
Link localtime to a corresponding zoneinfo file
    ln -sf /usr/share/zoneinfo/Europe/Kiev /etc/localtime

In your case select your time zone.

Restart cron daemon
    /etc/init.d/cron restart

In my case this was the fix for the problem. I edited my contab and cron started to work like a Swiss watch :-)