Alphatek - Steven’s Tech Blog

When I migrated from Fedora 8 to Fedora 9, I used the backup function in Evolution. Before backing up my mail accounts (POP3), I deleted all the sent mails and emptied the trash because it was the perfect moment to do so and it would make the backup file a lot smaller. With 5 mails left in Evolution, the backup file was still around 170MB compressed, strange heh?

I had a closer look at my .evolution folder and figured out that there was a huge “cache” directory for each mail account. This folder seems to contain ALL the messages I ever sent/received since the account’s creation.

I can’t see why there should be any cache for POP accounts (seems to be an IMAP feature), and why that cache is still there after emptying the trash…a Google search later, this seems to be a known bug.

I manually deleted the content of the cache folders and everything seems to work fine, no consequence on my inbox content.

So, if you are using Evolution with a POP account and you wonder where your disk space has gone, have a look at this…

I can see that you are lazy, and I know how hard it is to type an user name and password each time you want to login via SSH on a server.

Today, we are going to learn how to configure your computer and a server to allow automatic SSH authentications using your public RSA key. Less work = More fun!

Configuration on your computer:

As your normal user, open a terminal and type ssh-keygen

It will ask you some questions, you can simply press enter to acknowledge the default choices. You don’t need to enter a password here if you don’t want to be asked for it at each login on the server, it’s not a security flaw. The output should be something like that:

[Steven@HP6710 ~]$ ssh-keygen

Generating public/private rsa key pair.

Enter file in which to save the key (/home/Steven/.ssh/id_rsa):

Enter passphrase (empty for no passphrase):

Enter same passphrase again:

Your identification has been saved in /home/Steven/.ssh/id_rsa.

Your public key has been saved in /home/Steven/.ssh/id_rsa.pub.

The important thing is that you have 2 new files in your user/.ssh directory.

• id_rsa is your private key, you should NEVER give it away.
• id_rsa.pub on the other side is your public key, the one that you can give away.

Configuration on the server:

As the user you wish to be logged in (let’s say root), also run the ssh-keygen command to create the /root/.ssh directory. Now go to your /root/.ssh directory and create a text file named authorized_keys2. Copy the content of your computer’s public key file (id_rsa.pub on HP6710) to this file and save it.

Job done, now you can run ssh root@server from your computer and it will log you in automagically