Re: Question about kernel boot parameter

[Gene Heskett]

On Friday 08 June 2018 16:18:36 Reco wrote:

>   Hi.
>
> On Fri, Jun 08, 2018 at 02:05:45PM -0400, Gene Heskett wrote:
> > On Friday 08 June 2018 10:44:32 Dejan Jocic wrote:
> > > On 08-06-18, stuv wrote:
> > > > Hi everyone,
> > > >
> > > > I'm using a debian derivate of linux and i'm searching for a way
> > > > to make permanent changes to the kernel boot parameters without
> > > > GRUB or any other boot loader, i want to disable ipv6
> > > > permanently, when i do it over /init.d/modprobe.d the changes
> > > > only last until the next reboot.
> > > >
> > > > best regards.
> > >
> > > man sysctl
> > > man sysctl.conf
> > > man sysctl.d
> > >
> > > and then read files /etc/sysctl.conf and files under
> > > /etc/sysctl.d/. Those should give you enough examples. For your
> > > example, line you need to add to some of those files, or even
> > > better new file under sysctl.d with descriptive name for what will
> > > be done in it:
> > >
> > > net.ipv6.conf.all.disable_ipv6 = 1
> >
> > This is informative, and I'll use it because my 12 machine home
> > network is all ipv4, but its for only one option. Doing "sysctl
> > -a|wc -l" gets me 829 such options to set.  So where can I find the
> > real, complete, list of options AND the effect of changing each one?
>
> procfs(5) contains abridged list of these kernel tunables. "ip
> netconf" will decypher you some more, mostly network related.
>
> The documentation for you current kernel is the ultimate source of
> such knowledge. For stock Debian kernels it resides in linux-doc*
> packages.
>
> But, on that rare occasion that the option isn't there - there are
> kernel sources. Your kernel won't use the tunable anyway unless it's
> in the source ;)
>
> Reco

Thanks Reco, I'll run that stuff down tomorrow and get it installed if I 
can. This is an ayufan build for arm64. If that means anything.


-- 
Cheers, Gene Heskett
--
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

Re: Question about kernel boot parameter

[Reco]

Hi.

On Fri, Jun 08, 2018 at 02:05:45PM -0400, Gene Heskett wrote:
> On Friday 08 June 2018 10:44:32 Dejan Jocic wrote:
> 
> > On 08-06-18, stuv wrote:
> > > Hi everyone,
> > >
> > > I'm using a debian derivate of linux and i'm searching for a way to
> > > make permanent changes to the kernel boot parameters without GRUB or
> > > any other boot loader, i want to disable ipv6 permanently, when i do
> > > it over /init.d/modprobe.d the changes only last until the next
> > > reboot.
> > >
> > > best regards.
> >
> > man sysctl
> > man sysctl.conf
> > man sysctl.d
> >
> > and then read files /etc/sysctl.conf and files under /etc/sysctl.d/.
> > Those should give you enough examples. For your example, line you need
> > to add to some of those files, or even better new file under sysctl.d
> > with descriptive name for what will be done in it:
> >
> > net.ipv6.conf.all.disable_ipv6 = 1
> 
> This is informative, and I'll use it because my 12 machine home network 
> is all ipv4, but its for only one option. Doing "sysctl -a|wc -l" gets 
> me 829 such options to set.  So where can I find the real, complete, 
> list of options AND the effect of changing each one?

procfs(5) contains abridged list of these kernel tunables. "ip netconf"
will decypher you some more, mostly network related.

The documentation for you current kernel is the ultimate source of such
knowledge. For stock Debian kernels it resides in linux-doc* packages.

But, on that rare occasion that the option isn't there - there are kernel
sources. Your kernel won't use the tunable anyway unless it's in the source ;)

Reco

Re: Question about kernel boot parameter

[Gene Heskett]

On Friday 08 June 2018 10:44:32 Dejan Jocic wrote:

> On 08-06-18, stuv wrote:
> > Hi everyone,
> >
> > I'm using a debian derivate of linux and i'm searching for a way to
> > make permanent changes to the kernel boot parameters without GRUB or
> > any other boot loader, i want to disable ipv6 permanently, when i do
> > it over /init.d/modprobe.d the changes only last until the next
> > reboot.
> >
> > best regards.
>
> man sysctl
> man sysctl.conf
> man sysctl.d
>
> and then read files /etc/sysctl.conf and files under /etc/sysctl.d/.
> Those should give you enough examples. For your example, line you need
> to add to some of those files, or even better new file under sysctl.d
> with descriptive name for what will be done in it:
>
> net.ipv6.conf.all.disable_ipv6 = 1

This is informative, and I'll use it because my 12 machine home network 
is all ipv4, but its for only one option. Doing "sysctl -a|wc -l" gets 
me 829 such options to set.  So where can I find the real, complete, 
list of options AND the effect of changing each one?

googling around may accidentally get you this info for 2 or 3 such lines 
you can put in your /etc/sysctl.conf, but where is the full, wonderfully 
verbose list that explains them all?

Thank you.

-- 
Cheers, Gene Heskett
--
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

Re: Question about kernel boot parameter

[Celejar]

On Fri, 08 Jun 2018 16:14:39 +0200
stuv  wrote:

> Hi everyone,
> 
> I'm using a debian derivate of linux and i'm searching for a way to
> make permanent changes to the kernel boot parameters without GRUB or
> any other boot loader, i want to disable ipv6 permanently, when i do it
> over /init.d/modprobe.d the changes only last until the next reboot.
> 
> best regards.

https://wiki.debian.org/DebianIPv6#How_to_turn_off_IPv6

Celejar

Re: Question about kernel boot parameter

[Dejan Jocic]

On 08-06-18, stuv wrote:
> Hi everyone,
> 
> I'm using a debian derivate of linux and i'm searching for a way to
> make permanent changes to the kernel boot parameters without GRUB or
> any other boot loader, i want to disable ipv6 permanently, when i do it
> over /init.d/modprobe.d the changes only last until the next reboot.
> 
> best regards.
> 

man sysctl
man sysctl.conf
man sysctl.d

and then read files /etc/sysctl.conf and files under /etc/sysctl.d/.
Those should give you enough examples. For your example, line you need
to add to some of those files, or even better new file under sysctl.d
with descriptive name for what will be done in it:

net.ipv6.conf.all.disable_ipv6 = 1

Question about kernel boot parameter

[stuv]

Hi everyone,

I'm using a debian derivate of linux and i'm searching for a way to
make permanent changes to the kernel boot parameters without GRUB or
any other boot loader, i want to disable ipv6 permanently, when i do it
over /init.d/modprobe.d the changes only last until the next reboot.

best regards.