IPv6 module of Kernel 2.4.x & Kernel 2.6.x
karthikbalaguru
Is it possible to use the IPv6 module of linux kernel 2.6.x
in linux kernel 2.4.x ?
Thx in advans,
Karthik Balaguru
Aragorn
identifying as karthikbalaguru wrote...
> Hi,
> Is it possible to use the IPv6 module of linux kernel 2.6.x
> in linux kernel 2.4.x ?
Most likely not. The kernel API for modules has changed between 2.4 and
2.6. There may however be people who have backported IPv6 support to
2.4 kernels, but this I don't know.
--
*Aragorn*
(registered GNU/Linux user #223157)
karthikbalaguru
> On Thursday 17 December 2009 21:16 in comp.os.linux.networking, somebody
>
> identifying as karthikbalaguru wrote...
> > Hi,
> > Is it possible to use the IPv6 module of linux kernel 2.6.x
> > in linux kernel 2.4.x ?
>
> Most likely not. The kernel API for modules has changed between 2.4 and
> 2.6. There may however be people who have backported IPv6 support to
> 2.4 kernels, but this I don't know.
>
What are the changes to be taken into consideration
for backporting from 2.6 to 2.4 ?
Aragorn
identifying as karthikbalaguru wrote...
> On Dec 18, 1:24 am, Aragorn <arag...@chatfactory.invalid> wrote:
>
>> On Thursday 17 December 2009 21:16 in comp.os.linux.networking,
>> somebody identifying as karthikbalaguru wrote...
>>
>> > Is it possible to use the IPv6 module of linux kernel 2.6.x
>> > in linux kernel 2.4.x ?
>>
>> Most likely not. The kernel API for modules has changed between 2.4
>> and 2.6. There may however be people who have backported IPv6
>> support to 2.4 kernels, but this I don't know.
>
> What are the changes to be taken into consideration
> for backporting from 2.6 to 2.4 ?
Ehm, rewriting your code to match the 2.4 kernel API, perhaps? ;-)
I'm not a developer, let alone a kernel guru, but there should be
documentation out there on the kernel API.
(Note: Many regulars filter out posts coming in from Google Groups due
to the amount of spam distributed from there, along with other
annoyances such as multi-posting. I would advise you to subscribe to a
real Usenet news service - there are several free ones if your ISP does
not provide for one; look at the one I'm using, for instance - and to
use a real newsreader instead. Google is best used as a search engine,
and perhaps that is exactly what you should use it for? :p)
D. Stussy
news:28bf4b3a-66cd-406d...@k19g2000pro.googlegroups.com...
> Hi,
> Is it possible to use the IPv6 module of linux kernel 2.6.x
> in linux kernel 2.4.x ?
The main IPv6 driver, although it can be, should not be compiled as a
module. If you're going to use it, it should be permanently resident.
Mark Hobley
>
> The main IPv6 driver, although it can be, should not be compiled as a
> module. If you're going to use it, it should be permanently resident.
Mark.
--
Mark Hobley
Linux User: #370818 http://markhobley.yi.org/
D. Stussy
news:vav307-...@neptune.markhobley.yi.org...
> D. Stussy <spam+ne...@bde-arc.ampr.org> wrote:
> > The main IPv6 driver, although it can be, should not be compiled as a
> > module. If you're going to use it, it should be permanently resident.
>
> Why is that then? Doesn't it work as a module?
It's because it's one of those things that if you're using it, you need it
100% of the time. Therefore, it should be included statically into the
kernel - to avoid the module overhead.
Mark Hobley
> It's because it's one of those things that if you're using it, you need it
> 100% of the time. Therefore, it should be included statically into the
> kernel - to avoid the module overhead.
That is interesting. Is there much overhead in a module then?
I thought that the real overhead in this was having module loading
capabilities.
If the kernel has been built with a module loader (ie it is not monolithic),
then isn't it is best to take advantage of this by having the components as
modules?
The advantages of modular implementations (off the top of my head) are:
Small core - suitable for embedded systems
Scalable - same core on embedded systems, desktops and servers
Reduced footprint - only include the modules that you require
Buggy modules can be left out - if a module contains a bug, the core is still
useable
Alternatives - Alternative module versions can be used
Less rebuilding - You don't need to recompile the core to add or change a module
Are my ideas wrong about this?
D. Stussy
Regarding modules in general, no.
Regarding THIS service (IPv6 core): Yes.
If one uses it, then under what circumstances would one ever shut it off
(by booting without it or by rmmodding it)?
Would you compile the IPv4 networking core as a module?
Mark Hobley
> Would you compile the IPv4 networking core as a module?
Yes of course. This allows a change, such as a bug fix or security update
to be applied to the IPv4 module code, and the module to recompiled and
reloaded for the fix to be put into effect without the need to rebuild the
core.
D. Stussy
> D. Stussy <spam+ne...@bde-arc.ampr.org> wrote:
> > Would you compile the IPv4 networking core as a module?
>
> Yes of course. This allows a change, such as a bug fix or security update
> to be applied to the IPv4 module code, and the module to recompiled and
> reloaded for the fix to be put into effect without the need to rebuild
the
> core.
That's you. I certainly don't. I always need it available.
As for changes to a subsystem, there's very little difference between
recompiling and installing it as a module vs. the kernel-resident version.
Mark Hobley
> If one uses it, then under what circumstances would one ever shut it off
> (by booting without it or by rmmodding it)?
You could have a network that uses IPv4 internally but uses a routing
machine that uses IPv6 externally. This saves the internal lan from having
to carry IPv6 traffic.
Having IPv6 as a module means that only the routing machine has to load it.
The IPv4 clients do not need to carry the unused IPv6 module.
I am assuming here that the same code is deployed across all machines on the
network.
Mark Hobley
> That's you. I certainly don't. I always need it available.
It is always available. A simple modprobe in the startup scripts and its there
> As for changes to a subsystem, there's very little difference between
> recompiling and installing it as a module vs. the kernel-resident version.
If you know the core works, there is no need to risk breakage. A module is
good here.
I don't know how much overhead this costs. Do we have any comparison data for
a kernel with loaded modules and a kernel that is identical except that
one of its modules is static?
Pascal Hambourg
D. Stussy a ï¿œcrit :
>
> Regarding THIS service (IPv6 core): Yes.
>
> If one uses it, then under what circumstances would one ever shut it off
> (by booting without it or by rmmodding it)?
E.g. to prevent the local resolver library to send AAAA (IPv6 address)
DNS queries as a workaround with some broken DNS relays or servers that
handle such queries badly. This is a real life example.
Not everyone uses IPv6, and many people use a general purpose binary
kernel provided by the distribution and won't go through the hassle of
rebuilding their own kernel without IPv6 at all if they don't need it or
have trouble with it. So building ipv6 as a module gives them the choice
of loading it or not.
Note : AFAIK, once loaded the ipv6 module cannot or should not be unloaded.