How to add one more virtual CPU to redhat linux running on vmware

[senthil_kumar_1]

Hi All,

I have one redhat linux server (RHEL 4) with one virtual CPU.

Now i would like to increase one more virtual CPU.

We have added one more VCPU from vmware console.

But it is not getting reflected with redhat linux OS.

How to get it reflected.

Please help me to solve this issue.

[Matti_Kurkela · Accepted solution]

If the virtual system had only one CPU when it was installed, it's most likely running a single-processor kernel.

You must install a SMP kernel (up2date --install kernel-smp) and reboot the virtual system.

It's just the same as when installing a 2nd processor to a physical system.

MK

[senthil_kumar_1]

Hi Matti Kurkela,

Thanks a lot. now it is showing two CPUs with in linux after install of "kernel-smp".


How many processor smp kernel supports?.

If want to have 4 CPUs on RHEL4 then which kernel i have to go for?

[KarloChacon]

I really don't know which vmware version you are using but when you add you vCPUs to Virtual Machine it thinks as it has 2 physical CPUs or 2 sockets and RH 4 If am not wrong os up to 2 sockets

so something I read a few days ago came to my mind about cpuid.coresperSocket
in this way you can assign multiple cores to those vCPUs

http://www.yellow-bricks.com/2009/06/04/per-processor-licenses-for-your-application/

and also I think your RH can support up to 8 Cores with no problems since according to this article you must install something else if you want more that 8 logical processors or cores

http://kbase.redhat.com/faq/docs/DOC-3171

bye

[Jeeshan]

The default RHEL 4 kernel has a limit of 8 CPUs