I don't have VM, but on the z/OS side, I think you need to do a CONFIG command similar to: CF CPU(nn),ONLINE
-- John McKown Senior Systems Programmer HealthMarkets Keeping the Promise of Affordable Coverage Administrative Services Group Information Technology This message (including any attachments) contains confidential information intended for a specific individual and purpose, and its content is protected by law. If you are not the intended recipient, you should delete this message and are hereby notified that any disclosure, copying, or distribution of this transmission, or taking any action based on it, is strictly prohibited. ________________________________ From: The IBM z/VM Operating System [mailto:[EMAIL PROTECTED] On Behalf Of Wandschneider, Scott Sent: Thursday, May 29, 2008 8:47 AM To: IBMVM@LISTSERV.UARK.EDU Subject: Adding a Processor I have an MVS guest that has the following VM Directory entries: MACHINE ESA 4 CPU 00 BASE CPUID 050607 CPU 01 CPUID 150607 CPU 02 CPUID 250607 The box has four processors and I would like to define a fourth to the above guest. After logging onto the guest I issue "DEFINE CPU 03", then disconnect -- Correct? What, if anything, do I need to do on the MVS side to "activate" the additional processor? Thank you, Scott R Wandschneider Senior Systems Programmer Infocrossing, a WIPRO Company 11707 Miracle Hills Dr. Omaha, NE 68154 Office 402.963.8905