Hi,
first I want to thank maintainers of this excellent distro. I've had no problems, even I'm using quite new motherboard (Asus P5WD2) and dualcore Intel D 820 processor. I've updated all packages when You have announced them. At the moment the kernel is 2.6.9-34ELsmp and it works well.
But I've lost some understanding how these kernel versions flow ! I'm also a little confused of some related answers from some forums and lists. Questions : - is the kernel version used in CentOS the same as in kernel.org ? - if the kernel versions don't match, where do I get information which mathes which ?
The other question (very much relates to the later part of previous question and the need to do kernel compilation at all) : - if I want to compile new kernel using kernel source from kernel.org, what is the best way regarding to maintain the workability level of exisisting kenel (see top)? -- can I use .config-file from working 2.6.9-34ELsmp source and compile straight using that (first to see a working new kernel and then make some adjustments) ? In this way I can save a lot of time and frustration when setting the flags for compilation. Any other important to remember ? (I've compiled kernel since Linux 0.6 so no newbee recommendations. ;-) ) -- I need monitoring for many servers (thermal etc.) and of course they are remote. I would like to use OpenIPMI which seems to be the most modern method and thus would survive for some years (not expected of some other methods/applications) -- these issues are important to due I've more than 1 server and I'd like to use similar approach in each.
Could You point me a) documents to wise upgrade of kernel in CentOS 4.x environment ? b) if there exists, example of use OpenIPMI ?
You can also send answers directly as this topic might not interest wider public.
Best regards, Kari Salovaara
Kari Salovaara wrote:
But I've lost some understanding how these kernel versions flow ! I'm also a little confused of some related answers from some forums and lists. Questions :
- is the kernel version used in CentOS the same as in kernel.org ?
Yes, the CentOS 2.6.9 *base* kernel (which is the kernel 4.0 shipped with) is pretty close to the 2.6.9 kernel from kernel.org plus some patches (I don't know how many there were, though).
kernel 2.6.9-34.EL still is based on kernel.org's 2.6.9 kernel, but has at least 700 patches in it (that is added up for all architectures, so your i386 kernel doesn't really have 700 patches applied to it). But the kernel-API is still the same as in 2.6.9 (later 2.6.x kernels have a different one).
- if the kernel versions don't match, where do I get information which
mathes which ?
The kernel-rpm comes with a pretty detailed changelog, so "rpm -q --changelog kernel-2.6.9-34.EL |less" will tell you, what has been added to the kernels since the first packaging of a 2.6.9 kernel for CentOS4.
That means: Security Fixes *and* updated or new drivers get backported to the main kernel line in CentOS4/RHEL4 - which is kernel.org's kernel 2.6.9.
The other question (very much relates to the later part of previous question and the need to do kernel compilation at all) :
- if I want to compile new kernel using kernel source from kernel.org,
what is the best way regarding to maintain the workability level of exisisting kenel (see top)?
You leave the path of binary compatibility to RHEL4.
-- can I use .config-file from working 2.6.9-34ELsmp source and compile straight using that (first to see a working new kernel and then make some adjustments) ? In this way I can save a lot of time and frustration when setting the flags for compilation. Any other important to remember ? (I've compiled kernel since Linux 0.6 so no newbee recommendations. ;-) )
The first question asked here is always: Why do you think you need to recompile your kernel? The answer most often is: You don't need to - if you want to compile in additional kernel modules, installing the kernel-devel rpm is normally all it takes to be able to compile those modules.
Regarding OpenIPMI:
kernel 2.6.9-34 seems to have some IPMI support built as modules, just take a look at /boot/config-2.6.9-34.EL (or .ELsmp for the smp kernel).
Regards,
Ralph
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On Tue, Mar 21, 2006 at 02:05:46PM +0100, Ralph Angenendt wrote:
Kari Salovaara wrote:
But I've lost some understanding how these kernel versions flow ! I'm also a little confused of some related answers from some forums and lists. Questions :
- is the kernel version used in CentOS the same as in kernel.org ?
Yes, the CentOS 2.6.9 *base* kernel (which is the kernel 4.0 shipped with) is pretty close to the 2.6.9 kernel from kernel.org plus some patches (I don't know how many there were, though).
kernel 2.6.9-34.EL still is based on kernel.org's 2.6.9 kernel, but has at least 700 patches in it (that is added up for all architectures, so your i386 kernel doesn't really have 700 patches applied to it). But the kernel-API is still the same as in 2.6.9 (later 2.6.x kernels have a different one).
And there you are wrong.
I give you the exemple of slmodemd, where you have to change it so it detects the CentOS kernel as if it were 2.6.10+. Otherwise, it won't even compile, due to difference on the headers.
The other question (very much relates to the later part of previous question and the need to do kernel compilation at all) :
- if I want to compile new kernel using kernel source from kernel.org,
what is the best way regarding to maintain the workability level of exisisting kenel (see top)?
You leave the path of binary compatibility to RHEL4.
You might also have serious problems related extended functionality, that depends on patches applied to the RHEL4 kernel.
In other words: don't do it.
[]s
- -- Rodrigo Barbosa rodrigob@suespammers.org "Quid quid Latine dictum sit, altum viditur" "Be excellent to each other ..." - Bill & Ted (Wyld Stallyns)
Rodrigo Barbosa wrote:
On Tue, Mar 21, 2006 at 02:05:46PM +0100, Ralph Angenendt wrote:
kernel 2.6.9-34.EL still is based on kernel.org's 2.6.9 kernel, but has at least 700 patches in it (that is added up for all architectures, so your i386 kernel doesn't really have 700 patches applied to it). But the kernel-API is still the same as in 2.6.9 (later 2.6.x kernels have a different one).
And there you are wrong.
I give you the exemple of slmodemd, where you have to change it so it detects the CentOS kernel as if it were 2.6.10+. Otherwise, it won't even compile, due to difference on the headers.
Hmmmm. Compiled fine without any changes here. slmodemd-2.9.10 that is.
Ralph
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On Tue, Mar 21, 2006 at 03:44:54PM +0100, Ralph Angenendt wrote:
Rodrigo Barbosa wrote:
On Tue, Mar 21, 2006 at 02:05:46PM +0100, Ralph Angenendt wrote:
kernel 2.6.9-34.EL still is based on kernel.org's 2.6.9 kernel, but has at least 700 patches in it (that is added up for all architectures, so your i386 kernel doesn't really have 700 patches applied to it). But the kernel-API is still the same as in 2.6.9 (later 2.6.x kernels have a different one).
And there you are wrong.
I give you the exemple of slmodemd, where you have to change it so it detects the CentOS kernel as if it were 2.6.10+. Otherwise, it won't even compile, due to difference on the headers.
Hmmmm. Compiled fine without any changes here. slmodemd-2.9.10 that is.
Are you sure that was the stock slmodemd, and not the "abby" version ? The "abby" version is already patched to work on RHEL4.
In any case, the version I had to patch was 2.9.9d.
[]s
- -- Rodrigo Barbosa rodrigob@suespammers.org "Quid quid Latine dictum sit, altum viditur" "Be excellent to each other ..." - Bill & Ted (Wyld Stallyns)
Rodrigo Barbosa wrote:
On Tue, Mar 21, 2006 at 03:44:54PM +0100, Ralph Angenendt wrote:
Rodrigo Barbosa wrote:
I give you the exemple of slmodemd, where you have to change it so it detects the CentOS kernel as if it were 2.6.10+. Otherwise, it won't even compile, due to difference on the headers.
Hmmmm. Compiled fine without any changes here. slmodemd-2.9.10 that is.
Are you sure that was the stock slmodemd, and not the "abby" version ? The "abby" version is already patched to work on RHEL4.
I downloaded from http://www.smlink.com/content.aspx?id=132 - just to try it out, as I don't have any need for slmodemd :)
Ralph
On Tuesday 21 March 2006 13:47, Kari Salovaara wrote:
Hi,
first I want to thank maintainers of this excellent distro. I've had no problems, even I'm using quite new motherboard (Asus P5WD2) and dualcore Intel D 820 processor. I've updated all packages when You have announced them. At the moment the kernel is 2.6.9-34ELsmp and it works well.
But I've lost some understanding how these kernel versions flow ! I'm also a little confused of some related answers from some forums and lists. Questions :
- is the kernel version used in CentOS the same as in kernel.org ?
As previous replies stated, it's a vanilla 2.6.9 with lots of patches (internal rh ones and stuff (security updates, driver updates, bugfixes) backported from later 2.6 kernels).
If you install the src.rpm you get to see all the gory details. Patches can be found in the SOURCES dir.
- if the kernel versions don't match, where do I get information which
mathes which ?
You don't, there is no such thing as 2.6.9-22 matches 2.6.14 etc. All you get is the list of patches and the (very well maintained) changelog (rpm --changelog) if you really really need to know.
The other question (very much relates to the later part of previous question and the need to do kernel compilation at all) :
- if I want to compile new kernel using kernel source from kernel.org,
what is the best way regarding to maintain the workability level of exisisting kenel (see top)?
If you really need it, you can take your chances with a kernel.org kernel. My suggested way would be to select a kernel-2.6.x.y such that x is old enough for y to be large enough =). Today that would probably be 2.6.15.6.
-- can I use .config-file from working 2.6.9-34ELsmp source and compile straight using that
This should work fine, I then usually do make menuconfig and make rpm
(first to see a working new kernel and then make some adjustments) ? In this way I can save a lot of time and frustration when setting the flags for compilation. Any other important to remember ? (I've compiled kernel since Linux 0.6 so no newbee recommendations. ;-) ) -- I need monitoring for many servers (thermal etc.) and of course they are remote. I would like to use OpenIPMI which seems to be the most modern method and thus would survive for some years (not expected of some other methods/applications)
ipmi only works on some servers though, but when it works it's nice.
-- these issues are important to due I've more than 1 server and I'd like to use similar approach in each.
Could You point me a) documents to wise upgrade of kernel in CentOS 4.x environment ? b) if there exists, example of use OpenIPMI ?
the kernel (2.6.9-34) comes with really up to date openipmi drivers and centos ships with ipmitools, you're all set. Mini-howto: modprobe ipmi_si, ipmi_msghandler, ipmi_devintf, then you can run "ipmitool sel list" for example.
good luck, Peter
You can also send answers directly as this topic might not interest wider public.
Best regards, Kari Salovaara
-
Kari Salovaara -
Peter Kjellström -
Ralph Angenendt -
Rodrigo Barbosa