How to upgrade Magento 1.5 to latest 1.9 version. 3 years old store?

Question

My website is developed in magento version 1.5. I Need to upgrade to version 1.9.

Below are the current asserts on my website:

1. Db size Approx. 9 GB
2. Total Products Approx. 50,000
3. Total Orders 20,000
4. Total customers 23,000

I have followed below steps to achieve this but no luck.

1. Created new instance for the same.
2. Upgraded using Magento connect.
3. Its upgraded successfully version is updated.
4. But when i clear the cache and hit the url its infinite redirect loop.

2nd Approach:

1. Created new instance for the same.
2. Merge the latest version core files and other js, lib etc.. files.
3. Same when i hit the url its infinite loop.

3rd Approach:

1. Created new instance version 1.6
2. And merge the theme and skin files and others that are required to run the theme.
3. Configured the original db instance with this 1.6 version for upgrading the db.
4. Made changes on Db as required.
5. No luck again its loading and loading..

Please suggest. How can i upgrade my store?

Thanks In Advance!!

Answer 1

As far as I am aware from version 1.5 onwards you can upgrade directly to version 1.9.

Create a dev copy of your store database in its entirety.

Create a dev folder and extract a fresh copy of version 1.9 (no modules or themes from your old 1.5 version, please - just the pure magento 1.9!).

Copy over your media folder.

Edit your dev local.xml to point to your new dev db.

Launch the site in your browser and wait for the update script to finish (which could take a very long time with the size of your database).

Answer 2

I'm gonna start a list of Best Current Practices on upgrades here. Others please feel free to add your experiences.

1. Upgrading through the browser has a number of downsides, most notably that the browser can timeout or anything from the webserver you're talking to and the php backend. When that happens you have no clue what went wrong or is going to go wrong.

2. Using the mage script in Magento's toplevel directory is one way to use the "Magento Connect" way of upgrading. The good thing about it is that checks for conflicts. It's also it's downside. The conflicts can be dealt with after the upgrade is finalized or may not even be a realworld issue.

3. Most upgrades fail because the structure of core tables has been modified. Before upgrading, run the database repair tool to make sure this isn't the case.

4. The command line php has no execution time limit. Combine that with tools like tmux or screen and no matter how long the upgrade takes you're sure that you're gonna be able to check it's output. The simple way is to put the site in maintenance mode, set the new version's code in place, flush the cache and run php index.php.

5. When you're upgrading to 1.8.1.0 or higher, there's a requirement that all request paths in core_url_rewrite are unique per store view. It's best to do this before hand as it may require input from the store owner.

6. Database upgrades do not work if the setting <disable_module_upgrades> in local.xml is present and set to something evaluating to "true".

7. Consider a rebuild when you're spanning several versions. It may take less time and it makes you evaluate if you really need all those modules.

8. For the upgrade only - double PHP's memory_limit. It may not be needed, but you'll be sorry if it hits the limit several hours into the upgrade.

9. Even though Magento puts a lot of effort into making upgrades as user-friendly as possible, Magento is a flexible and modular system which makes it hard to anticipate problems. Consider hiring a party specialized in Magento support if you're not familiar with Magento, Php and MySQL.

Ok, that's all I can come up with for now. :)

Answer 3

You may want to consider a step-by-step upgrade from 1.5 to 1.6 to 1.7 to 1.8 and finally to 1.9 instead of going directly from 1.5 to 1.9.

What I suggest is for you to create a staging store and attempt the upgrade from there.

You should also take multiple backups to make it easy to roll back if required.

After taking your backup, attempt the upgrade from 1.5 to 1.6 and check if everything works fine. If it does, continue step-by-step until you are at 1.9. If something broke in between, find out if there's any code changes which may affect your theme or extensions which are not compatible and attempt to correct them first before you continue.