An essential part of this study is based on an online survey which consists of a set of questions concerning your positioning toward trainings in the field of Internet Technology (IT), either as a provider or a potential user of such trainings. The results of the survey will be analysed to provide recommendations to the European Commission and relevant stakeholders on the way to improve the IT training landscape in Europe. Intermediate results of the analysis will be made publicly available online but individual answers to the survey will be kept strictly confidential.

If you or your company is either involved in the supply of IT related trainings or if your organisation makes use of IT related trainings, please participate in the survey.

For further details or information, please contact the team in charge of the survey by using the following form.

A few weeks ago, the IPv6 connectivity went down. And some users discovered some issues in accessing the website. This is due to the fact that most modern browsers try to connect in IPv6 when 1) there is an IPv6 connectivy (on the client side) and 2) the requested website has a domain name which can be resolved to an IPv6 address (e.g. AAAA record).

The issue came back to me and I directly contacted the support of the company providing the server (we only use dedicated servers from the two biggest French companies providing that kind of services in France)… and the problem was fixed… 4 days later! As a comparison, what happens if the IPv4 connectivy goes down? All lights turn red in the support engineers office and the problem is fixed within a couple of minutes.

This kind of issue has consequences:

• on the service provider side (e.g. me in that case): suppose I want to provide IPv6 to test it. After such an issue, I simply remove the IPv6 connectivity. v4 is enough – note: I did not remove IPv6 as I am convinced we need it
• on the end-user side: even if most of the end-users don’t know IP at all, it has a bad impact. That’s why we see from time to time in forums folks saying to “disable IPv6″ to solve various issues (which have no relation with IPv6).

That’s why it’s good considering that if we want IPv6 to be adopted, it needs to work as IPv4, with the same quality. That’s the point of view of Google who provides IPv6 access to its services only to users from whitelisted networks (see http://www.google.com/intl/en/ipv6).

The script can be downloaded here: count_ipv6_requests.sh (to be renamed .sh after download).

A few explanation

A typical request is written as follow in a Rails logfile:

Processing FooController#my_action (for 12.34.12.34 at 2010-02-17 06:25:30) [GET]
Parameters: {"id"=>"xyz"}
Rendering foo/my_action
Completed in 2ms (DB: 1) | 302 Found [http://www.myapp.com/foo/my_action/xyz]

We need to search for IP addresses only on lines starting with ‘Processing’. With awk, it is quite easy to display the field #n of a specific line. However, in our case this is not useful as sometimes the number of fields preceding the address varies. For example, in the previous example, the IP address is the 4th field, whereas in the line below:

Processing FooController#index to rss (for 12.34.12.34 at 2010-02-17 10:50:38) [GET]

the IP address is on the 5th field… So the solution is to start counting from the last item. Starting reversly, the IP address is always at the 5th field (x=NF-4).

Then we analyse and count each line. We could have use some regexps to identify v4 or v6 address, but in that case searching for ‘.’ (point) and : (semi-column) is enough (example of an IPv6 address: 2001:41d0:2:8bcb::22).

awk section of the script

awk '
  BEGIN { count = 0 ; ipv4 = 0 ; ipv6 = 0 }
  /Processing/ { x=NF-4;
  count += 1;
	if (index($x, ".") > 0) { ipv4 += 1; }
	if (index($x, ":") > 0) { ipv6 += 1; }
  }
  END { print count " requests have been analysed."
	printf("\tcount\t%%\n")
  printf("IPv4\t%d\t%3.2f%%\n", ipv4, ipv4/count*100);
  printf("IPv6\t%d\t%3.2f%%\n", ipv6, ipv6/count*100);
  printf("Total\t%d\t100%%\n", count);
}
' $1

How to use the script

Download it here (count_ipv6_requests.sh) or copy/paste it in a new file, make it executable and run it that way:

fab@nsxxxx:/var/www/yourapp/current$ ~/count_ipv6_requests.sh log/production.log
3945 requests have been analysed.
        count   %
IPv4    3838    97.29%
IPv6    107     2.71%
Total   3945    100%

This script will work until the Rails team decides to change the log file format.

PS : remember to rotate your logfiles regulary. This will improve your disk I/O performances -or at least it will not decrease your performances (a good post on that here).
PS 2: a good awk tutorial is available here. Its title is self speaking: “Explained by examples rather than by definitons”. Will be good to refresh your memories or learn awk. The awk man page is also a good source of knowledge.

On November 2007, the release notes were:

End of 2006, The European Commission, DG Information Society and Media launched a study aimed at evaluating the Impact of IPv6 over vertical sectors.

Zaltana has been involved in that study coordinated by inno group. Final reports are now made available for download.

The study analyses the possible positive and negative outcome of various IPv6 adoption schemes and proposes several recommendations regarding the adoption of such systems in Europe.

These results are based on the analysis of:

• SWOT analysis of 15 vertical sectors
• Analysis of 12 case studies
• A web survey which targeted both Internet users and Internet Service Providers
• Workshops with IPv6 and sectors-representatives experts.

The final conclusion indicate that immediate consideration of Ipv6 integration has to be undertaken as this is the only way to minimise the costs associated with this activity and to facilitate the smooth transition of this integration tackling the key issue of the address shortfall.Two files are made available for download:

• A 30 pages synthesis report (with executive summary in English, French and German)
• The Full report including the followings annexes:
  • Case studies
  • SWOT analysis of 15 sectors
  • Web survey results
  • Final workshop report.

Final reports can still be downloaded:

• 30 pages synthesis report
• Full report

These reports are also available on the European Commission website:

• http://ec.europa.eu/information_society/policy/ipv6/docs/short-report_en.pdf
• http://ec.europa.eu/information_society/policy/ipv6/docs/complete-report_en.pdf

There is very useful tool provided with Postfix which could save us in those kind of situations (at least, it saved me multiple times) : postsuser. postsuser helps in the management of the mail queue.

A few useful commands:

• postsuper -h : moves message to the hold queue
• postsuper -r : requeue messages
• postsuper -d : delete all messages

Just found a good blog entry on that topic at the following URL: http://blog.gtuhl.com/2008/08/14/basic-postfix-queue-management

So in an urgent situation, where I want to receive all mails which contain clari (my lastname) now, I am using the following (a Bash/Linux guru would probably do it with a more complex and powerful command line, but this works) :

cd /var/spool/postfix/active
grep -L clari * | postsuper -h -

This change the current directory to the one holding active queue mails, then with the grep command sends to stdout all filenames of mails which do not contain my lastname and postsuper reads on stdout to put them on hold. Once done, after a couple of second my urgent mails are delivered.

Then, don’t forget to requeue messages from the hold queue! This can be done thanks to the following:

postsuper -r ALL

When your connectivity is ok, you can apply to the IPv6 Forum’s IPv6 enabled program to get the IPv6 Enabled www logo (once your site went through the validation process. See for exemple the Acteur Fête logo at http://www.acteurfete.fr/ipv6). This is of course only an option, but it’s always good to show your prospects and customers that your infrastructure is up to date.

Note : Acteur Fête is a French company which operates its business in multiple countries. The website is a gateway between event professionals and their customers. Zaltana is responsible for the website development and hosting.

rm -rf `find . -type d -name .svn`

• share with the world technical tips, ideas, projects…
• give back to the open source community feedbacks and hopefully new collaboration projects.

Main topics to be covered will be around software development (mainly Ruby on Rails and Java), IPv6, Linux and innovation in the IT world.

Happy reading

Fabrice.