[INFO] Executing: svn --non-interactive copy --file /tmp/...commit . https://subversion..../tags/...
[INFO] Working directory: ...
[INFO] ------------------------------------------------------------------------
[ERROR] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Unable to tag SCM
Provider message:
The svn tag command failed.
Command output:
svn: Commit failed (details follow):
svn: File '...' already exists


If you do, you are using subversion 1.5.x which no longer supports tagging from a local working copy, thus causing the unfortunately very misleading error message.

This is a known issue of the subversion sourcecode management (SCM) and there is a simple workaround:

Use the latest 2.x snapshot version of the maven release plugin and configure it to use remote tagging (on the subversion server) rather than tagging from your local copy.

You can do so by

1.) Adding the apache snapshots repository to your plugin repositories list

    <pluginRepositories>
        <pluginRepository>
            <id>apache-snapshots</id>
            <name>Apache Snapshot Repository</name>
            <url>http://repository.apache.org/snapshots/</url>
            <snapshots>
                <enabled>true</enabled>
            </snapshots>
        </pluginRepository>
        ...
    </pluginRepositories>

2.) Configuring the release plugin’s version and tagging

        ...
        <build>
        ...
        <pluginManagement>
            <plugins>
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-release-plugin</artifactId>
                    <version>2.0-beta-9-SNAPSHOT</version>
                    <configuration>
                        <tagBase>full url to the tags directory on the svn server</tagBase>
                        <!-- See http://jira.codehaus.org/browse/SCM-406 -->
                        <remoteTagging>true</remoteTagging>
                        <!-- Further non-mandatory but useful settings... -->
                        <preparationGoals>clean install</preparationGoals>
                        <autoVersionSubmodules>true</autoVersionSubmodules>
                    </configuration>
                </plugin>
            </plugins>
        </pluginManagement>
        ...
        </build>
        ...

This fixed it for me.

Note: i had problems getting this to function with the scp:// protocol (provider) for my distribution repository. It seems logic, tough, that the choosen provider must support remote tagging, thus i choose the scpexe:// protocol (using a local scp executable) instead, that worked:

...
<distributionManagement>
<repository>
  <id>myReo</id>
  <name>myreo</name>
  <url>scpexe://...</url>
 </repository>
...
</distributionManagement>
...

Apparently, the upcoming 2.0 release of the maven-release-plugin will have remote tagging as default, so if you read this and the 2.0 version has been released, simply using it should do the job.

Long story short, subclipse requires subversion 1.5, but ubuntu 8.04 provides 1.4.x.
If you still want to use subclipse with ganymede in ubuntu, there are only two ways two achieve this – both of which i cannot recommend because they are hacks or bad compromises.

a.) You could add the the ubuntu package source of the upcoming ubuntu release (i.e. deb http://fr.archive.ubuntu.com/ubuntu intrepid main) and install subversion 1.5 and the package libsvn-java from it. This is a bad idea since it will also install a bunch of transitive dependencies not designed for ubuntu 8.04. It might in fact damage your installation.
b.) You could not use the java hl API but a software connector completely written in JAVA (SVNKit client). This will work at first sight, but will convert your svn repository into 1.5 format. As a consequence, you can no longer use the svn command line client, since it does not support this format.

Subversive as an alternative to subclipse

Facing the above problems, i looked for an alternative and tried subversive. It’s an official and free eclipse plugin. The developers intend to make it the default subversion support plugin for eclipse.
It installed without any problem and worked really well with the javaHL api shipped with ubuntu 8.04. Look and feel of the plugin do not differ much from subclipse – subversive even offers a couple of additional useful options.

Here is how i installed and configured subversive:

1. Follow the installation instructions on the subversive download site.
   Since you will use the native javaHL connector implementation, be sure to choose the javaHL implementation from the update site:
   
2. Install the java HL API on ubuntu: sudo apt-get install libsvn-javahl.
3. Add the library directory where javahl resides to your eclipse.ini (located in the root folder of your eclipse installation). Just add the following line into it:
   -Djava.library.path=/usr/lib/jni.
4. Restart eclipse
5. Verify your setup.
   Goto Window>Preferences>Team>SVN and click the “SVN Connector” tab.
   The native javaHL connector should be selected
   

I’m working with it since about a week, it’s fast, has not failed on my a single time and is easy to use.

Unfortunately, such a setting usually does not contain a username, since this has to be provided by the actual team member connecting to version control.
Neither did i have any intention to configure a placeholder into the scm section, forcing the developers to mess with the maven settings.xml in order to provide their own username.

Luckily, after searching a while, i found a proper solution.
SSH allows an optional per-host specific username setting to be placed in a file called “config” located in the user’s .ssh directory, for example

File: ~/.ssh/config


Host my.host.name
User myusername


Thanks to Chad Humphries for posting the Solution on programming is hard.
It really wasn’t…