can someone explain what this cmd does?
 

echo exclude=openoffice* >> /etc/yum.conf


i think its telling yum to not upgrade openoffice - is that right?
why???

Yes, that's right. More precisely, no upgrades or installs for openoffice packages. Consult man yum.conf to be sure.
The echo command adds this line at the end of /etc/yum.conf file
Why what? :)

'echo exclude=openoffice* >> /etc/yum.conf' explained:
echo simply echoes the string, however, the '>>' redirection sends the output to file '/etc/yum.conf' in append mode. Using '>' would overwrite the file, '>>' does append to the end. The command is an equivalent for opening the /etc/yum.conf in a text editor and then adding 'exclude=openoffice*' to the end of the file.

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