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IBM Brings new Power 560 Express to Market

October 8th, 2008 No comments

"A new server for mid-size companies, the Power 560 Express, is due on Nov. 21. It uses a 3.6Ghz Power6 processor, comes in four-, eight- and 16-node configurations, and packs a hefty 384GB of memory. It’s designed for companies looking to run multiple applications on a virtualized system. It will be offered with Linux, AIX or i."

IBM brings a new line of processors and machines to the market with unreal memory capacities.

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Linus Torvalds has a Blog

October 8th, 2008 No comments

Linux Trovalds is the father of Linux. He has been very active in the development of the Linux kernel and recently decided to start a blog. Read his blog here.

 

It will be interesting if he keeps the blog updated or if he posts a lot at the beginning then tapers off.

 

So, having avoided the whole blogging thing so far, yesterday Alan DeClerck sent a pointer to his family blog with pictures of the kids friends, and I decided that maybe it’s actually worth having a place for our family too that we can do the same on.
Of course, I’ll need to see what Tove wants to do, but in the meantime, here’s a trial blog.

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Good Information on Linux Semaphores

August 27th, 2008 No comments

What is a Semaphore? An article I found here is very useful. It says that “Semaphores can be thought of as simple counters that indicate the status of a resource. This counter is a protected variable and cannot be accessed by the user directly.

This recently came up when the Dell OpenManage storage service would not start on a Linux system. It complained that there were no more Linux semaphores available. Check out the article for more information.

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“ROOT Filesystem is Currently Mounted Read Only”

July 18th, 2008 1 comment

This error can be a bit unnerving if your Linux system doesn’t reboot cleanly. To remount your root filesystem as read/write (rw) issue this command:

 

# mount -n -o remount rw /

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Backup GMAIL with FetchMail

July 14th, 2008 No comments

If you’re anything like me you really enjoy GMail but you really enjoy the peace of mind and comfort in having a local imagecopy of your email available at all times. I tend to not rely heavily on services provided by third party providers, even Google. What if I am offline? What if they have a long outage and I need access to my mail? As a society, we rely heavily on mail… probably more than we really know. Think about it: When was the last time your companies mail server went down? Global anarchy, chaos and fires result.

 

In this tutorial I will install, configure and run fetchmail to retrieve my messages over POP on a CentOS server.

 

Backing up GMail

Here we go :-)

 

1. Check to make sure fetchmail is installed on your system.

     # rpm -aq | grep fetchmail

If fetchmail is installed you will see the package returned. If not, issue this command in CentOS:
    # yum -y install fetchmail

2. Good, now we have fetchmail installed. Let’s verify by using this command:

     # fetchmail -V | grep release
        This is fetchmail release 6.2.5+IMAP-GSS+RPA+NTLM+SDPS+SSL+INET6+NLS

3. Let’s create a user which will keep our gmail backup.

     # adduser gmailbackup

4. Let’s create a fetchmail configuration file called ".fetchmailrc" in your current users home directory.

     # vi ~/.fetchmailrc

5. In this file enter the following substituting your credentials where necessary:

     poll pop.gmail.com with proto POP3 and options no dns
     user ‘username@gmail.com’ there with password ‘yourpassword’ is ‘gmailbackup’ here  options ssl

6. Now let’s set the permissions on the new .fetcmailrc file otherwise fetchmail will complain like this:
        File /root/.fetchmailrc must have no more than -rwx–x— (0710) permissions.

To set these permissions use this command:

      # chmod 710 ~/.fetchmailrc

7. Let’s fetch the mail with verbosity on.

      # fetchmail -vk

8. Let’s verify the mail we downloaded
      # mail -u gmailbackup

9. After this transfer let’s set up a cron entry to run a fetch every hour for safe keeping of our GMail.

      # crontab -e

    Add this to the bottom of your users cron:
          0 * * * * root fetchmail -k &> /dev/null

    The above redirects all output from fetchmail to /dev/null so we don’t get chatter in our local users mail box.

 

That’s it! You’re all done and being backed up. For easier viewing, assign a password to your local gmailbackup user with "passwd gmailbackup" and use a web client like RoundCube or SquirrelMail to view your GMail backup.

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