I have some problems to update yum.Ihave installed fedora core 5 and applying the command of yum on terminal (YUM -Y Update).
fedora didn't update the yum.
Sir kindly tell me how to update yum.

You have to check the yum repositories under /etc/yum.repos.d and in particular check if the path on the server is still valid, since FC5 has been discontinued some time ago. Then consider if upgrading to a newer release can be an option.

sir i apply this command on terminal
YUM -Y UPDATE
And the result is this one

---------------------------------
yum update
Loading "installonlyn" plugin
Setting up Update Process
Setting up repositories
core [1/3]
Cannot find a valid baseurl for repo: core
Error: Cannot find a valid baseurl for repo: core

Ok. You have to check the file /etc/yum.repos.d/fedora.repo and see if the baseurl specified under the [core] section is still valid. Fedora Core 5 is quite old, so there is a chance that the original repository has been displaced onto another path in the fedora server.

Anyway, I strongly suggest to upgrade (or to do a fresh install) to a more recent release. Fedora 10 is the last stable release of fedora, now!

Sir kindly check this
is this ok or not..

[core]
name=Fedora Core $releasever - $basearch
#baseurl=http://download.fedora.redhat.com/pub/fedora/linux/core/$releasever/$basearch/os/
mirrorlist=http://fedora.redhat.com/download/mirrors/fedora-core-$releasever
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora file:///etc/pki/rpm-gpg/RPM-GPG-KEY

[core-debuginfo]
name=Fedora Core $releasever - $basearch - Debug
baseurl=http://download.fedora.redhat.com/pub/fedora/linux/core/$releasever/$basearch/debug/
enabled=0
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora file:///etc/pki/rpm-gpg/RPM-GPG-KEY

[core-source]
name=Fedora Core $releasever - Source
baseurl=http://download.fedora.redhat.com/pub/fedora/linux/core/$releasever/source/SRPMS/
enabled=0
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora file:///etc/pki/rpm-gpg/RPM-GPG-KEY

As you can see, these URLs are not valid anymore. The mirror list points to a non existent page and if you try to go to http://download.fedora.redhat.com/pu...a/linux/core/5, you will find an empty directory!

So you have to locate a still active server and change the URLs accordingly. Here is the advice from the Fedora Download server:
So you have to navigate through the suggested URL and find the one suitable for your system, assuming $releasever = 5 and $basearch = i386 or x86_64 (based on the actual architecture of the system). For example you can try to modify the [core] section of fedora.repo like this (assuming the architecture is i386:
Note that I have commented out the mirrorlist line and uncommented the baseurl line after changing the URL.

sir

i have installed fedora core 7 and update the yum
i apply this command
-----------------
Yum -y update
-----------------
loading "installonly" plugin
Existing lock /var/run/yum.pid: another copy is runnig as pid 2678.aborting.

please tell me how to update yum on fedora 7

This is another story: maybe another yum session was still running, so you have to wait for the previous session of yum to finish. There is a chance that the automatic update is setup, so that when you login it activates (and keep yum busy) to retrieve the list of available updates and show you a pop-up message on the desktop. If this is the case, you have to let this process to complete before running yum from the terminal. Hope this helps.

ok i will try
sir i am making a voip server on fedora core 7
is it easy or not

Here is an article that can be interesting for you: Open source telephony: a Fedora-based VoIP server with Asterisk.

thanks for the yum updates of fc7
sir i have another problem on fedora coe7 i am installing the pear.
--------------------------------
#wget http://pear.php.net/DB-1.7.13.tgz
--------------------------------
--00:32:04-- http://pear.php.net/DB-1.7.13.tgz
=>'DB-1.7.13.tgz'
Resolving pear.php.net...78.129.214.25
Connecting to pear.php.net|78.129.214.25|:80...connected.
HTTP request sent,awaiting response...404 Not found
00:32:04 ERROR 404: Not Found.

The error message is quite clear: file not found! Try the following, using the correct URL:

i have configured all the voip server but the end there is problem
Sir I have apply this command on fedora core 7
----------------
./install_amp
---------------
Checking for PEAR DB..FAILED
[FATAL] PEAR must be installed (requires DB.php). Include path: .:/usr/share/pear:/usr/share/ph

i have apply this command on the voip server
--------------
./install-amp
-------------
cannot connect to the database