Upgrading from Debian 6 to Debian 7

I am currently maintaining an old computer with Debian. This computer has an Intel 486 processor. So, Ubuntu does not support this architecture but Debian supports it! I was earlier maintaining another similar Debian computer but the motherboard on that one has gone bust. So, I am down to one now…

Back to the topic, Debian 7 was released recently! I upgraded this machine from Debian 6 to Debian 7 over the week. The upgrade itself was seamless. The upgrade automatically replaced OpenOffice with LibreOffice, which is good. Otherwise, I would have had to do this manually.

After the upgrade completed, I tested all the applications which are used on this system. One of these applications is Evolution, the default e-mail client on Debian. Debian 6.x provides Evolution 2.x; however, Debian 7.x provides Evolution 3.x.

Version numbers aside, the real, noticable change is in the storage format of Evolution. Evolution 2.x uses mbox format and Evolution 3.x uses Maildir. The problem with mbox is that each mbox file (an email folder) should not be too large. Otherwise, it can take an old hard-disk a very long time to process such a large file. So, whenever any email folder execeeded around 2 GB, I had to split that folder into two. The advantage of Maildir is that each email is stored in a separate file. So, the earlier problem with mbox is not present in this case.

When I started Evolution 3.x for the first time, the Start-up Assistant offered to convert all the mbox folders to Maildir. However, when it finished, all the folders had not been converted. Maybe the machine did not have enough space. I was basically presented with all my older email folders under a separate “local_mbox” folder and a few folders which had been converted to Maildir, currently stored under the “local” folder. Converting the remaining folders was just a matter of manually “importing” all the remaining mbox files. During this import, Evolution automatically converted the mbox file to Maildir.

There are obviously better ways to convert mbox to Maildir than relying on Evolution alone. However, I did not have time to experiment. I wanted a quick solution which would work seamlessly in Evolution on Debian 7.