How are the updated kernels released by Red Hat / Cent OS related to the latest vanilla kernels ? Are the changes, new features and drivers, etc. available in the newer kernels also ported to the updated kernels released by Red Hat in their entirety ?
For the lifetime of a distribution like RHEL 4 or RHEL 5, Red Hat would stick to the same major and minor number of the kernel and would just change release numbers. What is the relation, if any, between the new kernels and the updates released by Red Hat ?
Thanks,
Manish Kathuria wrote:
How are the updated kernels released by Red Hat / Cent OS related to the latest vanilla kernels ? Are the changes, new features and drivers, etc. available in the newer kernels also ported to the updated kernels released by Red Hat in their entirety ?
If your comparing RHEL/CentOS kernels to kernel.org kernels they are similar but Red Hat adds a ton of patches(v4 is upwards of 100+ patches). New features are typically not backported to current versions of the kernel, newer drivers are often back ported, assuming the driver existed in the RHEL kernel. If the driver did not exist then it's much less likely to get included.
For the lifetime of a distribution like RHEL 4 or RHEL 5, Red Hat would stick to the same major and minor number of the kernel and would just change release numbers. What is the relation, if any, between the new kernels and the updates released by Red Hat ?
They make their systems ABI compatible throughout the lifetime of the major version(4.x, 5.x).
If your looking to stay on the leading edge with kernel updates your best off using another distro maybe Fedora or something. If your looking for a stable system that you don't have to worry about even if it means you have to be more careful about picking what hardware you run it on, RHEL and CentOS are good choices.
You can always build your own kernels on RHEL/CentOS if you wanted, or rebuild Fedora kernels and install them on RHEL/CentOS, in most cases it should work.
nate
nate wrote:
Manish Kathuria wrote:
How are the updated kernels released by Red Hat / Cent OS related to the latest vanilla kernels ? Are the changes, new features and drivers, etc. available in the newer kernels also ported to the updated kernels released by Red Hat in their entirety ?
If your comparing RHEL/CentOS kernels to kernel.org kernels they are similar but Red Hat adds a ton of patches(v4 is upwards of 100+ patches).
Actually for CentOS-5:
[buildcentos@v20z-x86-64 SOURCES]$ ls *.patch | wc -l 1102
So ... there are 1102 patches in the CentOS-5 kernel
For the CentOS-4 kernel, that number is very similar at 1115.
New features are typically not backported to
current versions of the kernel, newer drivers are often back ported, assuming the driver existed in the RHEL kernel. If the driver did not exist then it's much less likely to get included.
For the lifetime of a distribution like RHEL 4 or RHEL 5, Red Hat would stick to the same major and minor number of the kernel and would just change release numbers. What is the relation, if any, between the new kernels and the updates released by Red Hat ?
They make their systems ABI compatible throughout the lifetime of the major version(4.x, 5.x).
If your looking to stay on the leading edge with kernel updates your best off using another distro maybe Fedora or something. If your looking for a stable system that you don't have to worry about even if it means you have to be more careful about picking what hardware you run it on, RHEL and CentOS are good choices.
You can always build your own kernels on RHEL/CentOS if you wanted, or rebuild Fedora kernels and install them on RHEL/CentOS, in most cases it should work.
All the rest of what you said is true though ... drivers get backported much more frequently than other features.
One thing to consider about new kernels is abi changes ... and things (like sar, top, system monitoring tools, etc.) not working because of the differences unless they are also upgraded. Also, /proc changes considerably in newer kernels as well ... as will the things that you include in /etc/sysctl.conf
Also many times newer things like binutils, mkinitrd and module-init-tools will be required with a newer kernel.
Overall ... unless you really, Really, REALLY need a newer kernel, it is best to use the one provided by the distribution.
Thanks, Johnny Hughes
Johnny Hughes wrote:
Overall ... unless you really, Really, REALLY need a newer kernel, it is best to use the one provided by the distribution.
Is there a difference in the way kernel modules are managed between CentOS4 and 5? I thought that under CentOS4 after a kernel update VMware would insist that you run vmware-config.pl but it would always say that the existing module loads perfectly, where under CentOS5 it always compiles a new version for each updated kernel.
On Jan 29, 2008 3:18 PM, Les Mikesell lesmikesell@gmail.com wrote:
Johnny Hughes wrote:
Overall ... unless you really, Really, REALLY need a newer kernel, it is best to use the one provided by the distribution.
Is there a difference in the way kernel modules are managed between CentOS4 and 5? I thought that under CentOS4 after a kernel update VMware would insist that you run vmware-config.pl but it would always say that the existing module loads perfectly, where under CentOS5 it always compiles a new version for each updated kernel.
If we are talking about VMWare Server, RHEL4 is a supported OS, but RHEL5 isn't. If your not on a supported OS, it won't have a pre-configured set of modules.
It does look like RHEL5 support was added in VMWare Workstation 6, but I haven't used that version.
On Jan 29, 2008 12:25 PM, William Hooper whooperhsd@gmail.com wrote:
On Jan 29, 2008 3:18 PM, Les Mikesell lesmikesell@gmail.com wrote:
Johnny Hughes wrote:
Overall ... unless you really, Really, REALLY need a newer kernel, it is best to use the one provided by the distribution.
Is there a difference in the way kernel modules are managed between CentOS4 and 5? I thought that under CentOS4 after a kernel update VMware would insist that you run vmware-config.pl but it would always say that the existing module loads perfectly, where under CentOS5 it always compiles a new version for each updated kernel.
If we are talking about VMWare Server, RHEL4 is a supported OS, but RHEL5 isn't. If your not on a supported OS, it won't have a pre-configured set of modules.
It does look like RHEL5 support was added in VMWare Workstation 6, but I haven't used that version.
With VMWare Workstation 6 under CentOS-5, you run vmware-config.pl for each kernel update, but you do not need to compile the modules each time.
Akemi
Les Mikesell wrote:
Johnny Hughes wrote:
Overall ... unless you really, Really, REALLY need a newer kernel, it is best to use the one provided by the distribution.
Is there a difference in the way kernel modules are managed between CentOS4 and 5? I thought that under CentOS4 after a kernel update VMware would insist that you run vmware-config.pl but it would always say that the existing module loads perfectly, where under CentOS5 it always compiles a new version for each updated kernel.
I run CentOS 4 and 5 under VMWare ESX 3.x, I hacked up the VMware tools into two different RPMS
- core rpm (everything but drivers) - driver rpm
When I want to deploy a new kernel I build a special RPM with the vmware modules compiled against that kernel(never accepting the built in ones for no real reason other than I don't want to). And install the updated drivers at the same time as I install the new kernel. So far it's worked every time, no need to run vmware-config after kernel updates.
nate
On Jan 29, 2008 1:24 PM, nate centos@linuxpowered.net wrote:
Les Mikesell wrote:
I run CentOS 4 and 5 under VMWare ESX 3.x, I hacked up the VMware tools into two different RPMS
- core rpm (everything but drivers)
- driver rpm
When I want to deploy a new kernel I build a special RPM with the vmware modules compiled against that kernel(never accepting the built in ones for no real reason other than I don't want to). And install the updated drivers at the same time as I install the new kernel. So far it's worked every time, no need to run vmware-config after kernel updates.
nate
I hope you are interested in contributing to the CentOS community by sharing your driver:
https://projects.centos.org/trac/dasha/
Akemi
Akemi Yagi wrote:
I hope you are interested in contributing to the CentOS community by sharing your driver:
Looks like that site is for source drivers, these drivers come from VMWare, and I'm not sure what their license is, nor do I know exactly what the build process is, I just take the resulting binaries, so I'm not really one that can submit the driver.
nate
nate wrote:
Akemi Yagi wrote:
I hope you are interested in contributing to the CentOS community by sharing your driver:
Looks like that site is for source drivers, these drivers come from VMWare, and I'm not sure what their license is, nor do I know exactly what the build process is, I just take the resulting binaries, so I'm not really one that can submit the driver.
open-vm-tools is also being developed for CentOS :D
On Jan 30, 2008 4:06 AM, Johnny Hughes johnny@centos.org wrote:
nate wrote:
Akemi Yagi wrote:
I hope you are interested in contributing to the CentOS community by sharing your driver:
Looks like that site is for source drivers, these drivers come from VMWare, and I'm not sure what their license is, nor do I know exactly what the build process is, I just take the resulting binaries, so I'm not really one that can submit the driver.
open-vm-tools is also being developed for CentOS :D
I re-read the earlier post and realized that nate was talking about vmware tools, *not* the vmware modules for the host machine. Then I thought about referring to Johnny's open-vm-tools. Of course it is best to hear about it from him.
Thanks Johnny!
Akemi
On 1/30/08, Johnny Hughes johnny@centos.org wrote:
nate wrote:
Manish Kathuria wrote:
New features are typically not backported to
current versions of the kernel, newer drivers are often back ported, assuming the driver existed in the RHEL kernel. If the driver did not exist then it's much less likely to get included.
For the lifetime of a distribution like RHEL 4 or RHEL 5, Red Hat would stick to the same major and minor number of the kernel and would just change release numbers. What is the relation, if any, between the new kernels and the updates released by Red Hat ?
They make their systems ABI compatible throughout the lifetime of the major version(4.x, 5.x).
If your looking to stay on the leading edge with kernel updates your best off using another distro maybe Fedora or something. If your looking for a stable system that you don't have to worry about even if it means you have to be more careful about picking what hardware you run it on, RHEL and CentOS are good choices.
You can always build your own kernels on RHEL/CentOS if you wanted, or rebuild Fedora kernels and install them on RHEL/CentOS, in most cases it should work.
All the rest of what you said is true though ... drivers get backported much more frequently than other features.
In this connection, I have an example. I have a Netgear WG111 v2 USB Wireless Adapter which does not get detected by CentOS 5.1 updated with the latest 2.6.18 kernel released. This particular adapter has the Realtek 8187 chip. However, Fedora 8 running on 2.6.23 detects the adapter and also loads the correct module for it. This leaves me wondering whether the adapter will ever be supported by the current Cent OS 5.x kernel or the subsequent updates.
Thanks,
-
Akemi Yagi -
Johnny Hughes -
Les Mikesell -
Manish Kathuria -
nate -
William Hooper