what happens when same software is installed more than once

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raghavan20
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what happens when same software is installed more than once

Post by raghavan20 »

Normally when we install in windows, either the software reports the software already exists or it jus overwrites the existing one.

what will happen if I compile the source and I install it at more than one place by mistake. Will this cause any conflicts or any other problems.

but I think if I had installed from a RPM, the package manager like yum would report that the package has already been installed from its database....does it work like that?

if we do not install using rpm, who maintains the record of storing the data about the softwares installed?

I think before I installed apache...apache was installed by fedora to work with java...is it enough if we put
whereis software_name
and remove all the paths returned....is this the proper of uninstalling redundant software?
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Benjamin
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Post by Benjamin »

Normally it will just overwrite the old version. There is a small chance it could break something, although unlikely. It's best to learn how to use YUM as it forces correct installation, and will upgrade old packages. YUM is a little bit wacky sometimes though, as it may tell you something is installed when it isn't, and tell you that it is installed when you try to install it. There is a way to fix that but I can't remember right now how I used to do it. I haven't installed anything in months.
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RobertGonzalez
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Post by RobertGonzalez »

Yum. RPM or Apt. Package managers can be helpful in identifying what you have and helping you install what you don't.
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Chris Corbyn
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Post by Chris Corbyn »

OK here's the run down.

Installing the same thing to two separate places should be fine, providing you don't try running them at the same time. Installing two *different* versions to the same location may cause conflicts... you're best removing the old one first.

Rebuilding source code and installing it over the top is usually fine too.

The risks however are precisely what package managers are for. Windows has a package manager just like all the linux distros have one (I believe it's called "Windows Installer").

If you use the package managers and specify "upgrade" or "update" they should deal with the conflicts themselves.

A note about package managers. They use databases (or file repositories) and are onyl aware of what you installed using the package manager. If you installed Apache from source manually, then tried using RPM and saying "update", RPM wouldn't even know you'd installed apache already.... this *can* cause conflicts. Don't swap and change... use the distro the way it's made to be used. If you need to install anything from source don't delete the source you've downloaded.... you might just wat to rebuild or even pray for dear life there's an "uninstall" target in the Makefile.
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raghavan20
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Post by raghavan20 »

thanks for your explanations d11wtq and astions.

1. so you are confirming that linux distros do not have any ideas about softwares compiled and installed.
2. are package managers only available for rpm installations?
3. but how will you use rpm if apache is given only as source code?
4. i am very much confused with the installation files provided by mysql...they have so many different versions...
can you suggest me the proper one for fedora 5 running on x86 32 bit processor.
http://dev.mysql.com/downloads/mysql/5.0.html


i have a few general doubts
1. do you always put your source filesin /usr/local/source
2. do you always install software at /usr/local
3. if you put at /usr/local, will it be available to all users
4. are softwares can be installed using root or other users should belong to root group.
5. can we install softwares at places other than /usr/local
6. is that all final executables are put in /usr/sbin
7. is that all configuration files are put in /etc/
8. where do you normally all the web-related files...your server side scripts....in /opt/...if so ...why?



sorry for asking so many questions but I badly want to learn the best practices from you guys.

Thanks
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