CentOS - Mar 2011 - Creating the symbolic links in the /boot and /boot/grub/

I started a new thread since the original one is getting rather long.

I have retrieved the files I deleted in /boot and /boot/grub, 
however I need to make links for

/boot/System.map  (System.map -> System.map-2.6.9-89.35.1)
/boot/vmlinuz  (vmlinuz -> vmlinuz-2.6.9-89.35.1)
/boot/grub/menu.lst (menu.lst -> ./grub.conf)

If it was not so important to get it correct, I would appreciate 
the syntax for the command.  Usually I would figure it out.

Since I have restored the files (I will double check to make sure 
they are all there), do I need to run grub-install?

My apologies for bothering everyone with such a dumb error on my 
part.

Todd

-- 
Ariste Software
Petaluma, CA 94952

http://www.aristesoftware.com

On Tue, Mar 8, 2011 at 9:58 PM, Todd Cary <todd at aristesoftware.com>
wrote:
> I started a new thread since the original one is getting rather long.
>
> I have retrieved the files I deleted in /boot and /boot/grub,
> however I need to make links for
>
> /boot/System.map ?(System.map -> System.map-2.6.9-89.35.1)
> /boot/vmlinuz ?(vmlinuz -> vmlinuz-2.6.9-89.35.1)
> /boot/grub/menu.lst (menu.lst -> ./grub.conf)
Instead, re-install your kernel. "yum reinstall kernel". This should
regenerate your symlinks correctly, except possibly the grub.conf.
> If it was not so important to get it correct, I would appreciate
> the syntax for the command. ?Usually I would figure it out.
>
> Since I have restored the files (I will double check to make sure
> they are all there), do I need to run grub-install?
i think yes. The old location of the boot loader is listed in
/boot/grub/grub.conf, and should be used as the argument to that
command. grub is much smarter than LILO used to be, but I think the
bootstrap procedure relies on knowing details of where the fiddly bits
of grub live on the relevant ex2 compatible filesytem.
> My apologies for bothering everyone with such a dumb error on my
> part.
>
> Todd
>
> --
> Ariste Software
> Petaluma, CA 94952
>
> http://www.aristesoftware.com
>
> _______________________________________________
> CentOS mailing list
> CentOS at centos.org
> http://lists.centos.org/mailman/listinfo/centos
>

On Wed, Mar 9, 2011 at 12:40 AM, Todd Cary <todd at aristesoftware.com>
wrote:
> My current kernel is "vmlinuz-2.6.9-89.35.1" per grub.conf:
>
> #boot=/dev/hdc
> default=1
> timeout=5
> splashimage=(hd0,0)/grub/splash.xpm.gz
> hiddenmenu
> title CentOS (2.6.9-100.EL)
> ? ?root (hd0,0)
> ? ?kernel /vmlinuz-2.6.9-100.EL ro root=/dev/VolGroup00/LogVol00 rhgb quiet
> ? ?initrd /initrd-2.6.9-100.EL.img
> title CentOS (2.6.9-89.35.1.ELsmp)
> ? ?root (hd0,0)
> ? ?kernel /vmlinuz-2.6.9-89.35.1.ELsmp ro root=/dev/VolGroup00/LogVol00
rhgb
> quiet
> ? ?initrd /initrd-2.6.9-89.35.1.ELsmp.img
>
> What is the correct syntax for "rpm -U -replacepkgs
[kernel-whatever].rpm" ?
> ?What should go into [kernel-whaetver]?
>
> In like manner, I have forgotten how to do a query on it to see if it is
> present as in
>
> # rpm -q [kernel-name]
>
> Sorry, but it has been a long time since I used rpm and my Admin book does
> not give an example.
>
> Todd
OK, this should all go to the list for other CentOS folks who run into
this kind of adventure. To get the full list of RPM's, look at the
syntax of the "/etc/cron.daily/rpm"nightly script.
> man rpm
to look up the available options and learn about them. It's usually
worth learning about such an important command, and RPM components are
what yum really uses, so it's helpful to understand.
> rpm -qa | grep kernel
to get the list of kernel related components. Because of this line in
your grub.conf:

     kernel /vmlinuz-2.6.9-100.EL

I can also deduce that the relevant vmlinuz file was at
/boot/bmlinuz-2.6.9-100.EL, and you can use the command "rpm -q -f
/boot/vmlinuz-2.6.9-100.EL" to figure out what package it belonged to.
> rpm -q -f /boot/vmlinuz-2.6.9-100.EL --qf
'%{name}-%{version}-%{release}.%{arch}.rpm\n'
will get you the  get the full package name of the actual kernel RPM.

Download the latest RPM from your favorite CentOS repository, after
all, updating your kernel is you got into this trouble in the first
place.
> rpm -U --replacepkgs [whatever the name of that actual downloaded rpm is]
See, you shouldn't *care* about your actual running kernel. You wanted
the update, right? Go for it!!!! The running kernel will present
problems you want the most recent one.

I inadvertently missed using the list...here are my recent messages.


On 3/8/2011 8:39 PM, Nico Kadel-Garcia wrote:
> On Tue, Mar 8, 2011 at 11:31 PM, Todd Cary<todd at
aristesoftware.com>  wrote:
>> reinstall is not an option for yum.  I ran "yum install
kernel" and it
>> completed without errors however there are no links created.
> Oh, dear. Can you grab the RPM and do "rpm -U -replacepkgs
> [kernel-whatver].rpm"? You should be able to use "yum
remove" on the
> old kernel packages, consistent with freeing up the space, and now
> install your new kernel with yum.
>
>> Would this be the correct ln command for vmlinuz-2.6.9-89.35.1
>>
>> # /boot/vmlinuz-2.6.9-89.35.1 /boot/vmlinuz
>>
>> Todd
>>
>> On 3/8/2011 7:04 PM, Nico Kadel-Garcia wrote:
>>> On Tue, Mar 8, 2011 at 9:58 PM, Todd Cary<todd at
aristesoftware.com>    wrote:
>>>> I started a new thread since the original one is getting rather
long.
>>>>
>>>> I have retrieved the files I deleted in /boot and /boot/grub,
>>>> however I need to make links for
>>>>
>>>> /boot/System.map  (System.map ->   
System.map-2.6.9-89.35.1)
>>>> /boot/vmlinuz  (vmlinuz ->    vmlinuz-2.6.9-89.35.1)
>>>> /boot/grub/menu.lst (menu.lst ->    ./grub.conf)
>>> Instead, re-install your kernel. "yum reinstall kernel".
This should
>>> regenerate your symlinks correctly, except possibly the grub.conf.
>>>
>>>> If it was not so important to get it correct, I would
appreciate
>>>> the syntax for the command.  Usually I would figure it out.
>>>>
>>>> Since I have restored the files (I will double check to make
sure
>>>> they are all there), do I need to run grub-install?
>>> i think yes. The old location of the boot loader is listed in
>>> /boot/grub/grub.conf, and should be used as the argument to that
>>> command. grub is much smarter than LILO used to be, but I think the
>>> bootstrap procedure relies on knowing details of where the fiddly
bits
>>> of grub live on the relevant ex2 compatible filesytem.
>>>
>>>> My apologies for bothering everyone with such a dumb error on
my
>>>> part.
>>>>
>>>> Todd
>>>>
>>>> --
>>>> Ariste Software
>>>> Petaluma, CA 94952
>>>>
>>>> http://www.aristesoftware.com
>>>>
>>>> _______________________________________________
>>>> CentOS mailing list
>>>> CentOS at centos.org
>>>> http://lists.centos.org/mailman/listinfo/centos
>>>>
>> --
>> Ariste Software
>> Petaluma, CA 94952
>>
>> http://www.aristesoftware.com
>>
>>
>
-- 
Ariste Software
Petaluma, CA 94952

http://www.aristesoftware.com