MMM 2.0.10 , which Log::Log4Perl should be use ?

[Tomas]

Hello Walter and other experts,

I am reading your presenation of "MySQL Multi-Master Replication
Failover" now.

here is a line which confuse me

Install pearl modules
– Try 'yum install pearl-Log-Log4Perl' instead of CPAN → install
Log::Log4Perl

Any reason ? I use CPAN to install log4perl and in test environment ,
it works.
why we need use perl-log-log4perl instead ? any explanation ?

Thanks a lot

Yours Tomas

[Arjen Lentz]

Hi Tomas

On 02/12/2009, at 10:01 AM, Tomas wrote:
> I am reading your presenation of "MySQL Multi-Master Replication
> Failover" now.
>
> here is a line which confuse me
>
> Install pearl modules
> – Try 'yum install pearl-Log-Log4Perl' instead of CPAN → install
> Log::Log4Perl
>
> Any reason ? I use CPAN to install log4perl and in test environment ,
> it works.
> why we need use perl-log-log4perl instead ? any explanation ?

This is about system administration more than MMM.

For system management, if you have a RHEL/CentOS environment, you'd
want to install and maintain everything through the YUM/RPM system.
Adding stuff through CPAN will of course work, but then if you need to
set up a new server (or rebuild an existing one) you need to have kept
track of that, and so on.

On Debian/Ubuntu, Open Query sometimes clones a server by merely
copying the list of packages that's installed, and adjusting the
specific bits of configuration. That's all that's needed. If you use
CPAN, you can't do that. It's just a matter of work optimisation for
the system administrator.


Cheers,
Arjen.
--
Arjen Lentz, Exec.Director @ Open Query (http://openquery.com)
Exceptional Services for MySQL at a fixed budget.

Follow our blog at http://openquery.com/blog/
OurDelta: packages for MySQL and MariaDB @ http://ourdelta.org

[Nico Kadel-Garcia]

On Tue, Dec 1, 2009 at 8:06 PM, Arjen Lentz <ar...@openquery.com> wrote:
> Hi Tomas
>
> On 02/12/2009, at 10:01 AM, Tomas wrote:
>> I am reading your presenation of "MySQL Multi-Master Replication
>> Failover" now.
>>
>> here is a line which confuse me
>>
>> Install pearl modules
>> – Try 'yum install pearl-Log-Log4Perl' instead of CPAN → install
>> Log::Log4Perl
>>
>> Any reason ? I use CPAN to install log4perl and in test environment ,
>> it works.
>> why we need use perl-log-log4perl instead ? any explanation ?
>
> This is about system administration more than MMM.
>
> For system management, if you have a RHEL/CentOS environment, you'd
> want to install and maintain everything through the YUM/RPM system.
> Adding stuff through CPAN will of course work, but then if you need to
> set up a new server (or rebuild an existing one) you need to have kept
> track of that, and so on.

The EPEL and RPMforge repositories are particularly good at supplying
these Perl modules. If you need to integrate something from CPAN that
is not avaialble there, or cannot be backported from Fedora, I urge
you to use 'cpan2rpm' to create new RPM's and publish them to
RPMforge.

Installing CPAN modules without getting them into RPM format causes
amazing consistency problems, because the RPM packages will install
software later for other requirements and may only replace *parts* of
your manually CPAN installed components. Also, there is a syntax for
installing perl modules if you don't know what RPM contains it: next
time, try:

yum install 'perl(Log::Log4Perl)'

> On Debian/Ubuntu, Open Query sometimes clones a server by merely
> copying the list of packages that's installed, and adjusting the
> specific bits of configuration. That's all that's needed. If you use
> CPAN, you can't do that. It's just a matter of work optimisation for
> the system administrator.

See above. Also, the software in CPAN is automatically retrieved from
the latest versions, which can create an amazing arry of other modules
to install at the same time, and actively destabilize a working Perl
environment by even upgrading and replacing the version of Perl. (Been
there, done that.)