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Date:  Fri, 19 Dec 2008 00:04:50 +0100
From:  Michael Stauber <bq (at mark) solarspeed.net>
Subject:  [coba-e:14513] Re: memory lost
To:  coba-e (at mark) bluequartz.org
Message-Id:  <200812190004.51956.bq (at mark) solarspeed.net>
In-Reply-To:  <F848985ED61A49E4965D5128F30ED382@mcs1>
References:  <1d4c951a0807251545k9e6cd36ya41555a4f3e1ce19 (at mark) mail.gmail.com> <56E165E891C949EC976EFC1AE3796CFC (at mark) OfficeKen> <F848985ED61A49E4965D5128F30ED382 (at mark) mcs1>
X-Mail-Count: 14513

> so on a machine with-out SMP how would you force download & use an SMP
> kernel.

First of all, install the SMP kernel through YUM:

	yum install kernel-smp

That will install the (latest) SMP kernel, but will typically not make it the 
default boot kernel.

If you have local (physical) access to the server, then the next recommended 
step would be to reboot from the console and when the bootloader menu comes 
up, you choose the SMP kernel from the list to see if it works for you.

If the system boots up normally, check with ...

	cat /proc/meminfo

... if it now shows more RAM than before.

If you don't have easy physical access to the server and/or feel like you can 
chance it, you can skip that step.

To make the SMP kernel the default boot kernel there are several ways 
available. You can edit your lilo.conf or grub.conf manually.

However, the typically easiest way is to use "/sbin/new-kernel-pkg", as it 
automatically figures out which bootloader you're using and can make it the 
default one.

Now at the time of the writing of this message, 2.6.9-78.0.8.ELsmp is the 
latest SMP kernel for CentOS4.  But please double check the version number 
and make sure it really is 2.6.9-78.0.8.ELsmp. You can check this with this 
command:

	ls -k1 /boot/*ELsmp

The return from that would be like this:

# ls -k1 /boot/*2.6.9-78.0.8.ELsmp
/boot/config-2.6.9-78.0.8.ELsmp
/boot/System.map-2.6.9-78.0.8.ELsmp
/boot/vmlinuz-2.6.9-78.0.8.ELsmp

If this shows 2.6.9-78.0.8.ELsmp (as in the above example), then your command 
to make this very kernel the default boot kernel would be this:

/sbin/new-kernel-pkg --mkinitrd --depmod --make-default 
--install 2.6.9-78.0.8.ELsmp

That goes all into one line! And it's indeed just the version number and 
nothing else in front of it.

Provided you don't get any errors, you reboot next.

Login to the server once it's up again and check with "uname -r" which kernel 
version is reported. It should report 2.6.9-78.0.8.ELsmp.

-- 
With best regards,

Michael Stauber