To begin you will need to specify the location of the new packages in /etc/apt/sources.list. In other words, APT will need to know where the new packages are.

To upgrade an entire distribution to a new version of it, just run the following command as root:

apt-get dist-upgrade

There are a couple of things to consider when performing a full upgrade. Do you really need any of the latest packages? If your current distribution is still supported, it may not be worth the risk, and the risk is that some packages might not install correctly. Furthermore, downloading and installing so many packages will slow down your server while it is upgrading.

It is best to weigh the pros against the cons and then decide if your system really needs the upgrade or if you can keep it updated and secure with the current version.

1. If you are moving to an identical setup (i.e. same version of the same content management system), a basic SQL export will work just fine with minimal to no data loss.

2. If you are changing versions of a CMS, you should read its documentation to see if migration is even possible and what steps you need to take to make it happen. If at all possible, upgrade to the identical version before migration.

3. When moving to a completely different CMS or database system, you will need to prepare your data. This can involve manipulating large chunks of a MySQL database or even exporting everything to XML. Some software like WordPress will import RSS posts from an XML file without any extra configuration, making a migration rather painless.

4. Backup everything as often as you can. If you mess something up, it is better to have to start over with your backup copy than to have to fix the only copy you have.

Photo Source: Flickr

1. Use one of the gallery scripts supplied and installed by your web hosting provider (if available)
2. Download a free or commercial gallery application and install it on your server
3. Use a third-party photo sharing or gallery hosting site.

The advantage of a locally hosted gallery on your own server is that you can usually easily export your gallery and take it to another host. You also have full control over customization and features (especially if you are using an open source product). With option #1 the biggest disadvantage is that you are limited to whatever your web host provides, which may or may not be available if you switch to another host. The disadvantage of #2 is that you are responsible for updates and maintaining the security and stability of the gallery.

Option #3 eliminates the disadvantages of #1 and #2. Your gallery is maintained by another company and hosted on a remote server. You never have to worry about upgrades. The big disadvantage is that you do not have control over your own content and may not be able to easily export it and take it to another host or gallery.

Photo: Flickr

Answer: Using YUM you can upgrade CentOS with only a few steps.

1. Backup your important data. If most or all of is in a database, make sure to backup all databases.

2. List all of the updates:

# yum list updates

3. Upgrade your distribution:

# yum update

4. Reboot the server:

# reboot

5. Verify that all systems are working:

# uname -a
# netstat -tulpn
# tail -f /var/log/messages
# tail -f /path/to/log/file
# cat /etc/redhat-release

Note: Because the kernel will be upgraded, you will need to reboot the server after completion, so you should plan a scheduled down time when your website(s) will have the least amount of activity.

Source: nixCraft

Answer: These types of errors can be very annoying when trying to upgrade packages on a Linux server with apt-get. Sometimes these can be caused by adding third-party repositories, and other times it’s just an error by the distribution developers. At any rate, sometimes the solution can easily be solved with:

# apt-get -f install

If that works, you are done, but if it does not, you can try a more direct approach using dpkg, which is the program apt uses to install packages. From the root command prompt, enter:

dpkg --force-all -i /var/cache/apt/archives/packagename_0.80.1-1_all.deb

This will install the package and overwrite the offending file, ignoring any errors. Make sure the package you are installing is the right one before you do this. Otherwise, you might really do harm to your system, but most times the files truly are identical and have just been moved from one package to another. With that simple command, your problem should be solved.

Answer: Apt-get upgrade is designed to update your Linux server packages to their latests versions. It will only upgrade the packages that are currently installed. Apt-get dist-upgrade will not only upgrade the current packages but will also install any new packages that may be needed or that were added to the distribution.

In a real-world situation, let’s say you have an Ubuntu server. Ubuntu releases updates, fixes, and security patches on a routine basis. To get those updates, you would run APT:

sudo apt-get upgrade

This would bring your server up to date with all patches and fixes, but you would still essentially have the same version of the distribution. On the other hand, every six months, they release a complete new version of the distribution that sometimes has new packages and new dependencies for packages. To do a complete in-box upgrade you would enter:

sudo apt-get dist-upgrade

Both are useful and needed, but for different reasons. Make sure you know which one you need before you try them.

In a parody of Extreme Makeover: Home Edition, an American TV show where families in need receive free home renovations, a few happy-go-lucky folks from Microsoft redesign an outdated server room.

Though the Pentium 200 chips mentioned in the video are definitely outdated, I’m one of those people who likes to use equipment until it dies. Any decent web host will keep its servers up-to-date for performance and power efficiency reasons, however. If your host is still running old hardware, maybe you should send the Extreme Makeover guys in.

A network upgrade at Twitter’s data center was originally scheduled to take place Monday evening, but now the company has decided to postpone in order to keep the site active and available to Iranians.

Twitter’s data center has had to deal with an unprecedented load because of a traffic increase over the last several months. The upgrade is only expected to take half an hour.

There is speculation that it was not Twitter that made the decision, but pressure from the U.S. State Department. Twitter’s cofounder Biz Stone denied this:

The State Dept does not have access to our decision making process. When we worked with our network provider to reschedule the planned maintenance, we did so because events in Iran were tied directly to the growing significance of Twitter as an important communication and information network. We decided to move the date. It made sense fo [sic] Twitter and [our host] to keep sercie [sic] active during this highly visible global event.

Source: Data Center Dynamics