yum (RHEL/CentOs/SL/etc) has an option which allows you to limit the download rate/amount of bandwidth used to download packages. Here’s how you do it:
Edit the /etc/yum.conf file and add the following line:
throttle=50k
The above entry will limit the download rate to 50 kilobytes per second (note, not kilobits) when you do any yum command such as yum install or yum groupinstall , etc.