[9fans] Fossil on devfs

[9fans] Fossil on devfs

[Heiko Dudzus]

I want to mirror fossil with fs(3) and followed the instructions on
the Wiki page.

The hard drives are mirrored, fscfg partitions prepared on both disks,
the fossil configuration changed to /dev/fs/fossil. And the plan9.ini?

fsconfig is set to /dev/sdC0/fscfg.  But what's the correct bootargs
line?  Still

| bootargs=local!#S/sdC0/fossil

?

What's the point of time when #k is bound in the booting process, and
which process does that?  It has to be bound before the execution of
/rc/bin/cpurc, so I don't have to bind it there, do I?

Heiko

Re: [9fans] Fossil on devfs

[Christoph Lohmann]

Good day.

On Tue, 22 Nov 2005 20:27:34 +0100
Heiko Dudzus <heiko.dudzus@gmx.de> wrote:

> fsconfig is set to /dev/sdC0/fscfg.  But what's the correct bootargs
> line?  Still

Right.

> | bootargs=local!#S/sdC0/fossil

bootargs=local!#k/fs/fossil

> What's the point of time when #k is bound in the booting process, and
> which process does that?  It has to be bound before the execution of
> /rc/bin/cpurc, so I don't have to bind it there, do I?

devfs.c tries to read a config file from either  /dev/sdC0/fscfg or what
you specify in /env/fsconfig. After that it represents this configuration
in its file system. So when the kernel is running, then #k can be used.

Sincerely,

Christoph

Re: [9fans] Fossil on devfs

[andrey mirtchovski]

here's what i have:

plan9.ini:
fsconfig=/dev/sdC0/fscfg
bootargs=local!#S/sdC0/fossil

fscfg:
# cat /dev/sdC0/fscfg
fsdev:
mirror fossil /dev/sdC0/fossil /dev/sdD0/fossil
mirror isect /dev/sdC0/isect /dev/sdD0/isect
mirror arenas /dev/sdC0/arenas /dev/sdD0/arenas
mirror nvram /dev/sdC0/nvram /dev/sdD0/nvram
#

and fossil config:
# fossil/conf /dev/sdC0/fossil
srv -p fscmd
fsys main config /dev/fs/fossil
....
#

#k is bound by the kernel if it sees $fsconfig.

Re: [9fans] Fossil on devfs

[Russ Cox]

#k is outside the name space.  It is always available.

When we say bind -a #k /dev, now #k is bound on /dev
and is available as /dev, as in /dev/fs/whatever.

But #k/fs/whatever is always a valid name and requires
no binds or anything else.

Russ

Re: [9fans] Fossil on devfs

[Heiko Dudzus]

Andrey Mirtchovski wrote:
> here's what i have:
> 
> plan9.ini:
> fsconfig=/dev/sdC0/fscfg
> bootargs=local!#S/sdC0/fossil

Ok. That was it. Thanks.

> fscfg:
> # cat /dev/sdC0/fscfg
> fsdev:
> mirror fossil /dev/sdC0/fossil /dev/sdD0/fossil
> mirror isect /dev/sdC0/isect /dev/sdD0/isect
> mirror arenas /dev/sdC0/arenas /dev/sdD0/arenas
> mirror nvram /dev/sdC0/nvram /dev/sdD0/nvram

What's the point of having /dev/fs/nvram?  To be more specific: I do
see the point of having to copies of the nvram partition.  But out of
curiosity: where do you reference /dev/fs/nvram when using the system?

Isn't /dev/sdC0/9fat worth to be mirrored with devfs?

Heiko

Re: [9fans] Fossil on devfs

[andrey mirtchovski]

> What's the point of having /dev/fs/nvram?  To be more specific: I do
> see the point of having to copies of the nvram partition.  But out of
> curiosity: where do you reference /dev/fs/nvram when using the system?
>

my thinking was that i may need to update a password and didn't want
the disks to be out of sync. that hasn't happened yet in the three
years that i've had this setup...

> Isn't /dev/sdC0/9fat worth to be mirrored with devfs?
>

i don't remember why i didn't have it there. it would require a change
to 9fat: or a new script to mount 9fat from /dev/fs. i simply did a
'dd' from one disk to the other every time i updated a kernel.

Re: [9fans] Fossil on devfs

[Christoph Lohmann]

Good day.

On Sat, 26 Nov 2005 06:55:18 -0700
andrey mirtchovski <mirtchovski@gmail.com> wrote:

> > Isn't /dev/sdC0/9fat worth to be mirrored with devfs?
> >
> 
> i don't remember why i didn't have it there. it would require a change
> to 9fat: or a new script to mount 9fat from /dev/fs. i simply did a
> 'dd' from one disk to the other every time i updated a kernel.

9grid.de mirrors 9fat too, so if one HDD crashes, that you can boot the
other disk with the second boot option - without devfs -, go to the next
shop and buy a replacement.

Sincerely,

Christoph

Re: [9fans] Fossil on devfs

[andrey mirtchovski]

> 9grid.de mirrors 9fat too, so if one HDD crashes, that you can boot the
> other disk with the second boot option - without devfs -, go to the next
> shop and buy a replacement.

i have options in plan9.ini for booting from the first or the second
hard drive via different bootargs options. i wouldn't want to boot a
system with a dead hard drive casually as if nothing has happened. if
anything, a failed boot will force me to mirror the other drive onto a
new disk.

Re: [9fans] Fossil on devfs

[Heiko Dudzus]

Andrey Mirtchovski wrote:
>> Isn't /dev/sdC0/9fat worth to be mirrored with devfs?
>>
> 
> i don't remember why i didn't have it there. it would require a change
> to 9fat: or a new script to mount 9fat from /dev/fs.

I have made the necessary change to my 9fat: and sent a patch to
sources.

Re: [9fans] Fossil on devfs

[Russ Cox]

> I have made the necessary change
>  to my 9fat: and sent a patch to
> sources.

I would rather see a merging of devfs
into the devsd framework.  Then 9fat:
doesn't need to change at all and we're
back to having all the disk devices served
by #S.  I'm not sure what the name should
be (sdV0 for virtual?), but then you can
just parse ctl commands written to
/dev/sdV0/ctl to create new disks under
/dev/sdV0.

Russ

Re: [9fans] Fossil on devfs

[Russ Cox]

> I would rather see a merging of devfs
> into the devsd framework.  Then 9fat:
> doesn't need to change at all and we're
> back to having all the disk devices served
> by #S.  I'm not sure what the name should
> be (sdV0 for virtual?), but then you can
> just parse ctl commands written to
> /dev/sdV0/ctl to create new disks under
> /dev/sdV0.

Along with this, I would like to see some disk i/o
kprocs so that devfs is not slower than the usual
disks.

Russ

Re: [9fans] Fossil on devfs

[Tharaneedharan Vilwanathan]

Hi,

I tried to set up mirroring and I got into some issues. With the
available documentation, I tried setting it up. I tried to just use
9pcf kernel. Since I figured that 'fs' is missing, I added it to pcf
config file, built a kernel and tried to use it. The config I tried is
similar to andrey's. But fossil doesnt seem to recognize
/dev/fs/fossil. Does it mean /dev/fs isnt perfect before fossil
starts? Shouldnt I be using 9pcf kernel at all? I tried to dig as much
as I can and found that '#k' is bound somewhere in
connectlocalfossil() and to me it looked like this function is called
both in pccpuf and pcf cases. What could be the problem, then? Am I
missing something?

Any help appreciated.

Thanks
dharani

-----------------------andrey's config sent on 11/23/05------------------
here's what i have:

plan9.ini:
fsconfig=/dev/sdC0/fscfg
bootargs=local!#S/sdC0/fossil

fscfg:
# cat /dev/sdC0/fscfg
fsdev:
mirror fossil /dev/sdC0/fossil /dev/sdD0/fossil
mirror isect /dev/sdC0/isect /dev/sdD0/isect
mirror arenas /dev/sdC0/arenas /dev/sdD0/arenas
mirror nvram /dev/sdC0/nvram /dev/sdD0/nvram
#

and fossil config:
# fossil/conf /dev/sdC0/fossil
srv -p fscmd
fsys main config /dev/fs/fossil
....
#

#k is bound by the kernel if it sees $fsconfig.
---------------------------------------------------------------------------------

Re: [9fans] Fossil on devfs

[Steve Simon]

RE: disk mirroring

Have you cloned the data from your existing fossil to its new mirror,
you must do this by hand (with dd) before you first enable mirroring;
I do this booted from the CDROM.

You should be able to see the mirrored partition and the file containing
fs's config in #k/fs, On my home server:

	cpu% ls '#k/fs'
	'#k/fs/arenas0'
	'#k/fs/ctl'
	cpu% cat '#k/fs/ctl'
	mirror arenas0 /dev/sd06/arenas0 /dev/sd010/arenas0
	cpu% 

I use a mirrored venti rather than mirrored fossil but the principal
is the same.

Posting the contents of your plan9.ini, the contents of your fscfg
partition, and the fossil config might help me or others debug the problem,
however if you are using Andreys recpie it should Just Work™

Also rembember, if you are checking for the existance of devfs in your kernel,
if you are connected from a remote plan9/drawterm it may have mounted its
/dev/drivers before your file servers one, try:

	cat /dev/dri?ers | grep devfs

-Steve

Re: [9fans] Fossil on devfs

[Micah Stetson]

>         cat /dev/dri?ers | grep devfs

Does that actually print both files?  Wouldn't it just show the first one twice?

Micah

Re: [9fans] Fossil on devfs

[Tharaneedharan Vilwanathan]

Hi Simon,

I did make identical partitions for fossil in two disks and did a dd
copy from CDROM-booted plan9. To me it appears that I have done it
correctly. Your reply seems to be based on /dev/fs and venti. But I am
mirroring fossil. Right now, I couldnt check if /dev/fs is ready with
mirrored partitions before fossil during boot time. I think thats
where the problem is.

Here are my config details:

term% cat plan9.ini
fsconfig=/dev/sdC0/fscfg
bootfile=sdC0!9fat!9pcf
bootargs=local!#S/sdC0/fossil
bootdisk=local!#S/sdC0/fossil

*nomp=1
*nodumpstack=1
partition=new
dmamode=ask

mouseport=ps2
monitor=vesa
vgasize=1280x1024x8

term% cat /dev/sdC0/fscfg
fsdev:
mirror fosssil /dev/sdC0/fossil /dev/sdC1/fossil
term%
term% fossil/conf /dev/sdC0/fossil
fsys main config /dev/sdC0/fossil
fsys main open -V -c 3000

To me, it appears that somehow fs is not ready before fossil asks for
/dev/fs/fossil. The messages I get during boot are :

time...
fossil(#S/sdC0/fossil)...fsOpen: open /dev/fs/fossil: 'dev/fs/fossil'
does not exit
fsys main open -V -c 3000: fsOpen: open /dev/fs/fossil:
'dev/fs/fossil' does not exit
version...boot: mount /: fsys: 'main' not open
panic: boot process died: unknown
dumpstack disabled
cpu0: exiting

Thanks
dharani



On 2/3/06, Micah Stetson <micah@stetsonnet.org> wrote:
> >         cat /dev/dri?ers | grep devfs
>
> Does that actually print both files?  Wouldn't it just show the first one twice?
>
> Micah
>

Re: [9fans] Fossil on devfs

[Heiko Dudzus]

> I did make identical partitions for fossil in two disks and did a dd
> copy from CDROM-booted plan9. To me it appears that I have done it
> correctly. [...] Right now, I couldnt check if /dev/fs is ready with
> mirrored partitions before fossil during boot time. I think thats
> where the problem is.

#k/fs is ready once the kernel is running.  That shouldn't be the
problem.

> term% cat /dev/sdC0/fscfg
> fsdev:
> mirror fosssil /dev/sdC0/fossil /dev/sdC1/fossil
> term%

There is a typo ("fosssil").  If this typo is really in your fscfg
(and not only in the mail) this is the reason for your problem.

Heiko

Re: [9fans] Fossil on devfs

[Steve Simon]

This looks very strange, given your error message I agree with you,
it looks like devfs is not up.

try:
	grep devfs '#c/drivers'

to prove that the devfs driver is compiled in.

Interestingly your fossil conf seems to refer to
/dev/sdC0/fossil rather than /dev/fs/fossil. This would
mean fossil would start normally (not with an error)
but not use mirroring.

Perhaps this fossil.conf info is a modified version
of the config you used when you had problems?

-Steve

Re: [9fans] Fossil on devfs

[Tharaneedharan Vilwanathan]

Hi Heiko,

On 2/3/06, Heiko Dudzus <heiko.dudzus@gmx.de> wrote:
> > I did make identical partitions for fossil in two disks and did a dd
> > copy from CDROM-booted plan9. To me it appears that I have done it
> > correctly. [...] Right now, I couldnt check if /dev/fs is ready with
> > mirrored partitions before fossil during boot time. I think thats
> > where the problem is.
>
> #k/fs is ready once the kernel is running.  That shouldn't be the
> problem.
>
> > term% cat /dev/sdC0/fscfg
> > fsdev:
> > mirror fosssil /dev/sdC0/fossil /dev/sdC1/fossil
> > term%
>
> There is a typo ("fosssil").  If this typo is really in your fscfg
> (and not only in the mail) this is the reason for your problem.

yep! the output i sent is a capture of actual files and so i guess
thats the problem. since i havent tried devfs before i thought the
problem is elsewhere. so sorry.

i gave up mirroring temporarily and continued fossil+venti
installation and i have made some progress. in a day or so i will
continue mirroring effort and let you know the progress. thanks a lot
for figuring out the problem!

thanks
dharani