Before doing &quot;yum update&quot; on system which has CentOS5.3, I gave &quot;yum list updates&quot; but the following message comes:<br>Loaded plugins: fastestmirror<br>Determining fastest mirrors<br>Could not retrieve mirrorlist <a href="http://mirrorlist.centos.org/?release=5&amp;arch=x86_64&amp;repo=os">http://mirrorlist.centos.org/?release=5&amp;arch=x86_64&amp;repo=os</a> error was<br>
[Errno 4] IOError: &lt;urlopen error (110, &#39;Connection timed out&#39;)&gt;<br>Error: Cannot find a valid baseurl for repo: base<br><br>