PHP & MySQL Upgrade

[breun]

The Atomic Rocket Turtle packages are nice, but are you sure you *need* to upgrade? If you just want to stay up to date then a frequent yum update should suffice. If you need/want features only available in PHP 5 and/or MySQL 5, then ART (or migrating to a CentOS 5 server) is the way to go.

 

[Superman859]

I don't know if a MySQL update is needed for me, but I would like to update to php5. A lot of commercial software I run is converting and will not support php4 much longer.

Furthermore, I want to be able to use some of the newer oop features in php5 as I come from a strong background in Java and C++.

What is ART?

 

[breun]

ART = Atomic Rocket Turtle is atomicturtle's yum repository. He builds packages for Plesk servers running Red Hat/Fedora/CentOS and you can use that to upgrade PHP and MySQL to version 5 on CentOS 4.

But since you're running a virtual server it might also be worth it to just create a new virtual server running CentOS 5 and migrate to that.

 

[Superman859]

Alright - thanks for the info. When I upgrade I will use those repositories.

Unfortunately, I'm paying for a hosted solution that is a virtual dedi. I don't actually have a server of my own and virtual software on it, so I don't have control over it as far as I know (I did have a server that had a Virtuozzo panel on it, although I never did anything with it so I'm not sure if that is what I would need).

I think the only way for me to migrate would to get another hosted solution with CentOS5 somewhere and request a refund for unused time on this server. However, I'd rather just update php and mysql than switch servers completely again as I can't imagine it would be more work. I recently switched servers because I wanted to get off of fedora core and switched to CentOS.

Based on what I've read, updating php doesn't seem to be all that difficult. You mainly just make sure you have a good repository listed and run a few commands. The only part that I fear is errors that could arise because of it. I don't know what files actually get updated, if any configurations will need to be changed so the site continues to function as it is, etc.

The scripts SHOULD be ok for php5, although I'm not certain of that either.

I've downloaded CentOS4.6 and will install it in a VMWare virtual machine on my work computer. Will this suffice for playing around with the update process and checking to see if my site still works? I imagine during the install I will have the option to install it with the standard server packages - at least this happened with Debian and Fedora Core when I installed them. Once I do that it should pretty much be as my live server online is now as I haven't really done anything with the live server, correct?

 

[breun]

That's also an advantage of migrating to another server: you can test things on the new server and if it doesn't work out you can stick with the old one a little longer.

But yeah, the PHP 4 to 5 upgrade should be pretty harmless. http://www.atomicorp.com/wiki/index.php/PHP is your friend here. Keep a copy of your PHP 4 version of /etc/php.ini and if your sites don't appear to be compatible with PHP 5 you should be able to downgrade to PHP 4, replace your php.ini and restart apache to be up and running again.

 

[Superman859]

Hmm, that was one thing I was wondering. From what I've noticed, it seems when you install newer software on Linux, the old stuff stays but references in other files are changed to the newer version.

So this means when I install php5 using the guide at ART, php4 will be left as it is? And all I have to do is backup php.ini first, and if php5 has problems that I cannot figure out, I can replace the new php.ini with the new one until I find solutions to the problems?

If so, that takes away most of my worries. My main concern was messing the site up and having the site down for a week or two until I finally figured out the answers - something I cannot afford to do. If I can just switch it back to using php4 while I sort out the php5 issues, then it's not a big deal. The site can go down for an hour or two as I perform maintenance, but if all goes wrong I need to be able to revert back.

 

[breun]

No, upgrades do not keep the old version around. PHP 4 does not stay when you upgrade to PHP 5. But you can download the PHP 4 RPMS for your distribution and downgrade with a command like this:

rpm -Uvh --oldpackage php*.rpm

Then put back your original copy of /etc/php.ini and restart apache.

Note that this method doesn't necessarily work for all software. Sometimes a software upgrade also upgrades a database schema for instance and then installing the old version again won't work unless you also revert to the original database. But in case of PHP it works just fine AFAIK.

 

[thedust2010]

Issue with MySQL5 Upgrade

I was able to upgrade PHP & MySQL just fine, but PHP is still using MySQL 4.1. When I pull up phpinfo(), that's what it shows me at least. Anyone experience this problem? I can confirm MySQL 5 is installed by using "yum info mysql".

 

[breun]

It's not using MySQL 4, but it's using the MySQL 4 client library. It generally isn't a problem and it's expected behavior. If you really experience problems because of it you can rebuild the package against MySQL 5 if you really need to.