How to install an OS with 2 installation iso file

[Harsh chopra]

Hi everyone,
I was trying to install Centos 2.1 on the virtual machine,the installation
was complete 50% but then it asked to insert the second installation iso
file.
i.e. "Please insert disc 2 in cdrom"
I tried to change the XML file and insert the line
<source file = "/home/..."/>
under device name  but nothing helped.
Should I extract the iso file in a folder and then give it's path in source
file or am I missing something?