Recently in Troubleshooting Category

Indeed, I'd like to read your comments on my blog. But in more recent weeks spam comenters have attempted to raid my site. For some time I've required people to sign up in order to be able to comment on my blog. As a consequence, spam commenters created a pile of fake accounts using a small number of email addresses to register (from China and India). Some weeks later they used these fake accounts trying to flood the site with nonsense that didn't make it to the articles but cluttered my mailbox. It became a nuisance and something had to be done.

For a time I considered to modify the code of my blog to make registration for people using these email addresses impossible. The blog software answers a registration attempt by sending out a confirmation email with a link containing random data. If these emails wouldn't arrive at the spammer's email inbox the problem was solved.

But honestly, I do not only wish to block outgoing mail to people, who have proven their ill-disposed behaviour to me, I'd also like to protect me from seeing anything they might try to send to me, too.

The easiest way to achieve this was to tell my mail server about these culprits. I created two files (recipient_blacklist and sender_blacklist) that contain email addresses (or domain names) of accounts used to register as a commenter, that subsequently were used to submit heaps of nonsense.

It goes without saying that you have to be very careful about what you put into this database, because a domain name entry will block all email originating from or going to this domain without exception. This time, it was exactly what I'd wish to happen. To prepare the blacklist databases, I had to use the following commands:

After adding the following line to my postfix configuration file "main.cf" and restarting the mail server, any attempt to use one of the listed email addresses resulted in a nice reject log in the logfile. I've never seen anything from these addresses since.

Having said that, I heartily invite everyone to contribute comments. I am committed to keep this a friendly place, where you'll find interesting information and valuable advice. And I'm prepared to write code that will update my spam commenter database, helping to chase them away effectively, as soon as possible.

Maybe you've tried to get the new firefox 4 to display applets by using the good ol' libjavaplugin_oji.so with no success. It took me a while to discover that newer versions of firefox require a different plugin called libnpjp2.so which is located in a totally different place in Sun's JRE tree.

Create a symbolic link in your plugins directory (either /usr/lib/mozilla/plugins or in your home directory in $HOME/.mozilla/plugins) and your firefox 4 should be able to display applets.

Why did nobody tell me?

I know, you are one of those people who know that it is absolutely essential to make regular backups of your system's hard disk. There is no excuse not to make regular backups, but as we all know, we don't really do that. Or is it just me?

No, you have to admit that even though the reasons to make backups are indisputable, something strange always - no, not always, but many times - keeps you from doing the necessary, updating your backups and securely storing them away. Making backups is not fun, but that's not the reason why we don't do it regularly. I suspect that you as well as I simply don't have the right tool yet, to initiate an automatic process that boils down to getting a reliable backup complete and safe to restore, which does not require much attention while assembling the data for us.

Fortunately this situation is going to change dramatically for you, today. I've run into a backup solution that is just that, an automatic process that does not require user intervention when started to do the right thing. It's called CLONECILLA and is essentially a Live Linux system, optimised for backup and recovery.

Clonezilla - Your bootable backup CD

Clonezilla can be downloaded here as an ISO-file of 106 megabytes.. This file contains everything that makes up a bootable Linux system, so be careful to write this downloaded iso-file to your CD in raw-mode. Because it's of no use to have the iso-file on a CD in another file system, the iso-file is the file system and it is the only thing that has to be on the CD.

Did I mention that Clonezilla is a backup solution that covers all sorts of partition types, so that our windows-using friends could use it, too? Clonezilla has the ability to clone a complete hard disk no matter what kind of partition your disk comprises of. It even backs up the master boot record and the partition table, you will get a complete set of data from which all or any part will be recoverable when you need it. And all data is created as zipped files of max. 2 gigabytes size so that everything can be burned to DVDs, if needed.

Setting Clonezilla on the right track

As we are now heading for a complete backup of your laptop's hard disk, one thing is to be considered before we start, where will all the backup data be stored? Fortunately Clonezilla offers a number of possible storage media ranging from an additional (plugable) local disk, a SSH server or a SAMBA server to the traditional NFS server. I assume that you have a portable USB hard disk on which you will store the backup. Please ensure that the free space on this disk is about half of the size of what you are going to backup, and add a little bit of a buffer, too.

I have found that a second thing is important before you start letting Clonezilla create the backup, make sure that all partitions of your hard disk can be mounted. Best practice would be to perform a file system check on all partitions before starting the Clonezilla boot CD.

The following few steps are all you need to initiate a full backup of your laptop's hard disk and you will see that once you've selected a few things the rest is going in a jiffy.

Step 1	Boot your Clonezilla backup CD, select language and keymap, then select "Start Clonezilla"
Step 2	After selecting the backup media (local_dev) power on your USB disk and allow a few seconds for the system to recognize your new hard disk on which the backup will be stored. Clonezilla creates a directory on the USB disk derived from the date and time of the backup. You can choose where to store this directory on the disk. You can always switch to another terminal using <CTR><ALT>F2 to see that the USB disk is now mounted on /home/partimag. All files go into this directory.
Step 3	Select "savedisk" to ensure that the whole hard disk is backed up. When the partition information is read in Clonezilla will start the backup process automatically.
Step 4	Depending on the size of your hard disk, you can now relax and let Clonezilla compose your backup for you. Check the backup directory in the meantime to see it filling up with data.

The performance of creating the backup is very good, it took 47 minutes for a 30 gigabyte data partition on my three year old laptop. The whole disk (120 gigabyte) was ready after two and a half hours time leaving me a total of 66 gigabytes of compressed data.

Try Clonezilla today, it takes very little time to be secure. No excuses!