Today I got an interesting request, a user needed to change his 64 bit non-SMP VM image (running RedHat 4.0) to a SMP machine, problem is, I don’t really want to have to go through reconfiguring the kernel and rebuilding it, so here’s the easy way to do it (it’s pretty simple):
- Power the image down
- Right-click and edit the settings for the VM image (if you don’t know how to do this, this article is beyond your scope)
- Change the CPU settings from 1 to >1 (2 or 4 or 8 or whatever you want to use) (see picture)
- Power the VM image back on
- Put the RedHat CD #2 in your desktop CD drive (or using the ISO), connect the disc to the VM image (see picture, note that I selected the wrong ISO, should be disc #2)
- On the vmware image, mount the cd with: mount /media/cdrom
- Enter the directory: cd /media/cdrom/RedHat/RPMS
- In my case, I’m using a 64-bit kernel, so I would use the 64-bit SMP kernel:
[root@lava2057 RPMS]# rpm -Uvh kernel-smp-2.6.9-42.EL.x86_64.rpm - Unmount the CD, dettach the CD/ISO
- Run up2date to make sure the new kernel you installed is up to date (chances are that it isn’t, since RedHat has pushed out a new kernel since putting out the CDs)
- Edit the
/boot/grub/grub.conffile, mine looks something like this before changes:
default=2
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title Red Hat Enterprise Linux ES (2.6.9-67.0.1.ELsmp)
root (hd0,0)
kernel /vmlinuz-2.6.9-67.0.1.ELsmp ro root=LABEL=/ rhgb quiet
initrd /initrd-2.6.9-67.0.1.ELsmp.img
title Red Hat Enterprise Linux ES (2.6.9-42.ELsmp)
root (hd0,0)
kernel /vmlinuz-2.6.9-42.ELsmp ro root=LABEL=/ rhgb quiet
initrd /initrd-2.6.9-42.ELsmp.img
title Red Hat Enterprise Linux ES (2.6.9-67.0.1.EL)
root (hd0,0)
kernel /vmlinuz-2.6.9-67.0.1.EL ro root=LABEL=/ rhgb quiet
initrd /initrd-2.6.9-67.0.1.EL.img
title Red Hat Enterprise Linux ES (2.6.9-42.EL)
root (hd0,0)
kernel /vmlinuz-2.6.9-42.EL ro root=LABEL=/ rhgb quiet
initrd /initrd-2.6.9-42.EL.img - I have 4 kernels installed, the initial install 64-bit (non-SMP), the 64-bit SMP I just installed and the most recently updated versions of each of these, as you can see, the line “
default=2” is still pointing to our non-SMP image. We need to use the 2.6.9-67.0.1.ELsmp kernel, so I’m going to change it to “default=0“ - Reboot the machine
- After it’s rebooted, log in and check ‘
uname -a‘, mine shows:
Linux lava2057.lss.emc.com 2.6.9-67.0.1.ELsmp #1 SMP Fri Nov 30 11:57:43 EST 2007 x86_64 x86_64 x86_64 GNU/Linux
Simple eh? I know it’s not related to security, but I figured it’d be helpful to someone out there. 
Good man, was sure I should be able to accomplish this in about 30 seconds, but from a quick look elsewhere it was looking like a big job… worked like a charm.
i want file convert SMP for samsung
This is a great write-up, thanks! I ran into the same situation and found this article on Google. The only other thing I noticed in my environment is that after you boot to the new kernel it is necessary to run reconfigure vmware tools if you are running them in order to get the memory driver working again.
Thanks again!
Thanks… This tip saved me an install for a short time that I will need smp. Now I can swap back and forth between single or dual proc for certain functions.
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This topic solved the problem I had on my red hat VM :
dmesg | grep Proc
Processor #0 6:12 APIC version 17
Processor #1 6:12 APIC version 17
WARNING: NR_CPUS limit of 1 reached. Processor ignored
I was limited to only one processor with a non SMP kernel but with a SMP kernel, the server can use the 4 CPU. I was surprised to see that the server could use 8Go of RAM even if it is a 32 bits with the SMP kernel. It was limited to 3Go with the non SMP kernel.