Downgrade mysql 5.5 to 5.1 problem

[Richard G]

I want to move some accounts to a new server (vps).
The old server has mysql 5.1 and the new one has 5.5 so to be compatible I want to downgrade mysql 5.5 on the new server to 5.1.

In options.conf I set autover=no and mysql to 5.1 then I do ./build update and after that do ./build mysql.

Then this error occurs:

error while loading shared libraries: libmysqlclient.so.18

Isn't it possible to run Mysql 5.1 on Centos 6 with custombuild?

 

[ditto]

Switshing between 5.1 and 5.5 is not something you do unless you have to. 5.1 uses so.16 and 5.5 uses so.18 - when I upgraded from 5.1 to 5.5 I needed to make a symlink from so.16 to so.18 like this:

cd /usr/lib64
ln -s libmysqlclient.so.18 libmysqlclient.so.16

You could try to do the opposite like this:

cd /usr/lib64
ln -s libmysqlclient.so.16 libmysqlclient.so.18

But do it at your own responsibility.

 

[Richard G]

Thank you very much for the quick answer and you support.

However I just discovered that more then one error was going to appear when trying to downgrade.
I had to do some work to get 5.5 working good again. So I think I will keep everything as is now.

The only thing I wonder now if a da-user backup with mysql 5.1 databases can easily be restored in a server with da and mysql 5.5 running or if things should be changed.

Any idea?

 

[ditto]

The only thing I wonder now if a da-user backup with mysql 5.1 databases can easily be restored in a server with da and mysql 5.5 running or if things should be changed.

I don't think this will cause any trouble for you, I think it restore without MySQL version causing any trouble.

However, when you are running MySQL 5.5 in new server, I would recommend you have the following settings in etc/my.cnf:

default-storage-engine=MyISAM
innodb_file_format=Barracuda
innodb_file_per_table=1

Read more about that in this thread: http://www.directadmin.com/forum/showthread.php?t=43886

 

[Richard G]

Oh great.
I will surely follow your advise and also read the thread you pointed to.

Thank you very much for the quick help!

 

[ditto]

You welcome. I would also like to point out that MySQL 5.5.x is a very good choise. It has better perfomance. And also MySQL has already moved MySQL 5.1 down under the heading "Looking for previous GA versions?" in this page http://dev.mysql.com/downloads/mysql/ , and MySQL 5.6 has already reached "Release Candidate" (as of MySQL 5.6.7), this tells me that we are getting very close to MySQL 5.6.x being released as GA (General Availability), and when that happens, then MySQL 5.1 will no longer be supported. I think it will happen before the end of this year.

On a sidenote, I have noticed a trend with faster releases of major versions in the three "big ones", Apache, PHP and MySQL - they are pushing major versions much faster then ever before, in particular that is true for PHP.

 

[Richard G]

Yep, you are quite correct there.
I also noticed that major versions (especially for php) are pushed faster.
Mysql 5.5 is indeed a good choice, but the only reason we did not upgrade yet is that we got a lot of hosting customers amongst which several with older scripts and custom scripts from which is not known if they will be compatible with 5.5.
Last time when we upgraded from 5.0 to 5.1 there were some slight problems with some scripts, but with the php upgrade to php 5.3 there was a lot more.

So we got a bit more carefull and try to examine first if it can be a more ore less flawless upgrade so we prevent customers from getting angry.

On the other hand, on all new servers we try to install the newest stable version of everything.
Only when moving from older servers, we first do the old install, then restore the backup, and then upgrade to the newer versions. This way no problems will occur or only after the upgrade. But the we still have the old copies on the old server still running and can fix the problems on the new server before changing the DNS.

 

[Suurbier]

and MySQL 5.6 has already reached "Release Candidate" (as of MySQL 5.6.7), this tells me that we are getting very close to MySQL 5.6.x being released as GA (General Availability), and when that happens, then MySQL 5.1 will no longer be supported. I think it will happen before the end of this year.

Last MySQL 5.0 update was this year. I don't think the support for MySQL 5.1 will end this year.

 

[ditto]

MySQL will only support the last two major versions, so when MySQL 5.6 becomes GA, then they will no longer push updates to MySQL 5.1, but only to 5.5 and 5.6. I would be willing to bet a small amount of money that MySQL 5.6 becomes GA before the end of this year.

Of course there might be some exceptions that they will push a very critial bug or security fix to a MySQL version that is no longer recommended and "supported" (like they did with MySQL 5.0), but that would be only a few exceptions. You don't want to stay on 5.0 anymore, thats for sure - and that will very soon be the reality of MySQL 5.1.x.

 

[Richard G]

Well... it doesn't matter a lot to me, there are a few servers on which we will keep mysql 5.1 for at least another 6 months.

 

[Suurbier]

Of course there might be some exceptions that they will push a very critial bug or security fix to a MySQL version that is no longer recommended and "supported" (like they did with MySQL 5.0), but that would be only a few exceptions. You don't want to stay on 5.0 anymore, thats for sure - and that will very soon be the reality of MySQL 5.1.x.

They haven't announced anything about MySQL 5.1 end of life. And if they do they will support it for atleast a year or something like that.

http://www.mysql.com/support/eol-notice.html

Well... it doesn't matter a lot to me, there are a few servers on which we will keep mysql 5.1 for at least another 6 months.

You can also use a fork like MariaDB if you don't want to upgrade to MySQL 5.5/5.6