/net

/net

[Fred .]

Plan 9 has a /net directory.


/net is the API for all TCP/IP, and it can be used even with scripts
or shell tools, writing data to control files to write and read
connections. Relevant sub-directories like /net/tcp and /net/udp are
used to interface to prospective protocols. You can implement a NAT by
mounting a /net from a perimeter machine with a public IP, while
connecting to it from an internal network of private IP addresses,
using the Plan 9 protocol 9P in the internal network. Or you can
implement a VPN by mounting a /net directory from a remote gateway,
using secured 9P over the public Internet.

Here would be an example of using union (a stack) directories in /net:
just like inheritance in OOP, you can take one (possibly remote)
/special directory and bind another local special directory on top of
that, adding some new control files and hiding others. The union
directory now is like a child object instance of the original parent.
The functionality of the original can be partially modified. Consider
the /net file system. If you modify or hide its /net/udp sub-directory
you may control or extend the UDP interface with local filter
processes, still leaving the original /net/tcp running intact, perhaps
in a remote machine. Note that name space is per process: if you give
an untrusted application a limited, modified /net union directory, you
restrict its access to the net.

All this makes it easy to combine "objects" or file systems written in
different languages on different systems, while using standard naming,
access control and security of the file system, largely transparently
to the programmer.


I saw that Linux implemented many things from Plan 9 such as /proc,
union mounts, etc. Will Linux also implement /net ?
--
To unsubscribe from this list: send the line "unsubscribe linux-api" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: /net

[Stephen Hemminger]

On Thu, 13 Nov 2008 02:25:33 +0100
"Fred ." <eldmannen-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:

> Plan 9 has a /net directory.
> 
> 
> /net is the API for all TCP/IP, and it can be used even with scripts
> or shell tools, writing data to control files to write and read
> connections. Relevant sub-directories like /net/tcp and /net/udp are
> used to interface to prospective protocols. You can implement a NAT by
> mounting a /net from a perimeter machine with a public IP, while
> connecting to it from an internal network of private IP addresses,
> using the Plan 9 protocol 9P in the internal network. Or you can
> implement a VPN by mounting a /net directory from a remote gateway,
> using secured 9P over the public Internet.
> 
> Here would be an example of using union (a stack) directories in /net:
> just like inheritance in OOP, you can take one (possibly remote)
> /special directory and bind another local special directory on top of
> that, adding some new control files and hiding others. The union
> directory now is like a child object instance of the original parent.
> The functionality of the original can be partially modified. Consider
> the /net file system. If you modify or hide its /net/udp sub-directory
> you may control or extend the UDP interface with local filter
> processes, still leaving the original /net/tcp running intact, perhaps
> in a remote machine. Note that name space is per process: if you give
> an untrusted application a limited, modified /net union directory, you
> restrict its access to the net.
> 
> All this makes it easy to combine "objects" or file systems written in
> different languages on different systems, while using standard naming,
> access control and security of the file system, largely transparently
> to the programmer.
> 
> 
> I saw that Linux implemented many things from Plan 9 such as /proc,
> union mounts, etc. Will Linux also implement /net ?

Sure patches accepted for review anytime :-)
--
To unsubscribe from this list: send the line "unsubscribe linux-api" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: /net

[Paweł Sikora]

On Thursday 13 of November 2008 02:25:33 you wrote:
> Plan 9 has a /net directory.

autofs machinery also uses /net directory...
--
To unsubscribe from this list: send the line "unsubscribe linux-api" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

/net

[Bryan Simmons]

I'm still recovering from upgrading into almost a completely new
system.  I thought I didn't install NFS and samba and the other network
file system stuff, but it seems it's there anyway.

Anyway, when the system is shutting down or rebooting,  just after the
umount command is given, I get the error: umount2: <something about RPC
not being found>: umount /net: device busy
and right there, all attempts to shutdown/reboot are ended.  The system
just sits there.  The only thing I can do is hit the reset button.  If
not for XFS, I'd be running fsck at every frickin reboot.

I have an AthlonXP 2100+ system, integrated ethernet, adsl connex
(started at boot and not stopped manually at all).  Can't think of what
else is important here.  Can anyone tell me how to make this go away?
I tried to disable nfslock and nfs at boot (set to start manually), but
it frickin started anyway.

Thanks guys!!!
-- 
Bryan Simmons <bsimmo1@gl.umbc.edu>

-
To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.linux-learn.org/faqs

Re: /net

[Ray Olszewski]

It's hard to be sure from a fragmentary report, but the "something about 
RPC not being found" probably refers to the portmapper daemon (which runs 
as /sbin/portmap on my systems) that is used by mountd . Is it running 
prior to the the start of the halt or reboot process? And you need to tell 
us what is mounted as /net (look in /etc/fstab to find out, if you don't 
know, or look at the output of "df").

Usually, a "device busy" error from umount means that some active process 
is using the partition that umount is trying to unmount. Without more 
detail, I don't know what that might be at this point in the halt or reboot 
sequence. You might check this with "lsof" just before you halt or reboot. 
Indeed, you might even try umount'ing /net by hand, to track down the 
source of the conflict.

As to "what else is important", it never hurts to mention what Linux distro 
and version is involved (even if it seems like you are repeating yourself 
again and again; there's enough traffic on help lists to make it tough for 
me, and probably others, to remember the configurations others have). Also, 
*how* you "tried" to disable nfslock and nfs.

Also ... "The only thing I can do is hit the reset button" ... you are 
probably right, but did you try CTRL-C? It probably won't work right at 
this spot, but it might ... the shutdown process really is just "init" 
running a bunch of scripts, and you can sometimes SIGTERM out of them.

At 07:23 PM 10/29/02 -0500, Bryan Simmons wrote:
>I'm still recovering from upgrading into almost a completely new
>system.  I thought I didn't install NFS and samba and the other network
>file system stuff, but it seems it's there anyway.
>
>Anyway, when the system is shutting down or rebooting,  just after the
>umount command is given, I get the error: umount2: <something about RPC
>not being found>: umount /net: device busy
>and right there, all attempts to shutdown/reboot are ended.  The system
>just sits there.  The only thing I can do is hit the reset button.  If
>not for XFS, I'd be running fsck at every frickin reboot.
>
>I have an AthlonXP 2100+ system, integrated ethernet, adsl connex
>(started at boot and not stopped manually at all).  Can't think of what
>else is important here.  Can anyone tell me how to make this go away?
>I tried to disable nfslock and nfs at boot (set to start manually), but
>it frickin started anyway.




--
-------------------------------------------"Never tell me the odds!"--------
Ray Olszewski					-- Han Solo
Palo Alto, California, USA			  ray@comarre.com
-------------------------------------------------------------------------------

-
To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.linux-learn.org/faqs

Re: /net

[Bryan Simmons]

Here is what /etc/mtab says about /net:

brainpress:(pid1532) /net nfs
intr,rw,port=1023,timeo=8,retrans=110,indirect,map
=/etc/amd.net,dev=0000000b 0 0
automount(pid1622) /net autofs rw,fd=5,pgrp=1622,minproto=2,maxproto=4 0
0

Here's what I know:  I'm running Mandrake 9.0 kernel 2.4.19-16mdk.  In
the "services" configuration (which sets up what daemons and other
services start at boot automatically etc...) I tried to stop netfs and
nfslock by stopping them and changing their startup to "manual" instead
of "on boot".  But it didn't take.  In the syslog logfile it says that
amd was the last process to mount /net.  The only reason I installed
these services is because I am planning on putting this machine on a
home network with a WinXP box.  Could it be having problems because
there is nothing to find in the /net folder?  Since it is not listed in
/etc/fstab is there any way to get rid of it?

Thanks again!!



On Tue, 2002-10-29 at 20:32, Ray Olszewski wrote:
> It's hard to be sure from a fragmentary report, but the "something about 
> RPC not being found" probably refers to the portmapper daemon (which runs 
> as /sbin/portmap on my systems) that is used by mountd . Is it running 
> prior to the the start of the halt or reboot process? And you need to tell 
> us what is mounted as /net (look in /etc/fstab to find out, if you don't 
> know, or look at the output of "df").
> 
> Usually, a "device busy" error from umount means that some active process 
> is using the partition that umount is trying to unmount. Without more 
> detail, I don't know what that might be at this point in the halt or reboot 
> sequence. You might check this with "lsof" just before you halt or reboot. 
> Indeed, you might even try umount'ing /net by hand, to track down the 
> source of the conflict.
> 
> As to "what else is important", it never hurts to mention what Linux distro 
> and version is involved (even if it seems like you are repeating yourself 
> again and again; there's enough traffic on help lists to make it tough for 
> me, and probably others, to remember the configurations others have). Also, 
> *how* you "tried" to disable nfslock and nfs.
> 
> Also ... "The only thing I can do is hit the reset button" ... you are 
> probably right, but did you try CTRL-C? It probably won't work right at 
> this spot, but it might ... the shutdown process really is just "init" 
> running a bunch of scripts, and you can sometimes SIGTERM out of them.
> 
> At 07:23 PM 10/29/02 -0500, Bryan Simmons wrote:
> >I'm still recovering from upgrading into almost a completely new
> >system.  I thought I didn't install NFS and samba and the other network
> >file system stuff, but it seems it's there anyway.
> >
> >Anyway, when the system is shutting down or rebooting,  just after the
> >umount command is given, I get the error: umount2: <something about RPC
> >not being found>: umount /net: device busy
> >and right there, all attempts to shutdown/reboot are ended.  The system
> >just sits there.  The only thing I can do is hit the reset button.  If
> >not for XFS, I'd be running fsck at every frickin reboot.
> >
> >I have an AthlonXP 2100+ system, integrated ethernet, adsl connex
> >(started at boot and not stopped manually at all).  Can't think of what
> >else is important here.  Can anyone tell me how to make this go away?
> >I tried to disable nfslock and nfs at boot (set to start manually), but
> >it frickin started anyway.
> 
> 
> 
> 
> --
> -------------------------------------------"Never tell me the odds!"--------
> Ray Olszewski					-- Han Solo
> Palo Alto, California, USA			  ray@comarre.com
> -------------------------------------------------------------------------------
> 
> -
> To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.linux-learn.org/faqs
-- 
Bryan Simmons <bsimmo1@gl.umbc.edu>

-
To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.linux-learn.org/faqs

Re: /net

[Ray Olszewski]

I can't help you too much, Bryan, but maybe just enough to let you move ahead.

This mount point is managed by amd (AutoMount Daemon), which I do not use. 
You might look through your init scripts to find the one that invokes it, 
then modify the script or disable it completely (depending on whether it 
does other things you still need done). Or maybe Mandrake's "services" 
configuration offers a way to control amd.

Beyond that ... you still need to use "lsof" to find out what process has 
something in that directory (or perhaps the directory itself) open to 
interfere with the umount command. Or the control file "/etc/amd.net" may 
contain illuminating information.

At 09:29 PM 10/29/02 -0500, Bryan Simmons wrote:
>Here is what /etc/mtab says about /net:
>
>brainpress:(pid1532) /net nfs
>intr,rw,port=1023,timeo=8,retrans=110,indirect,map
>=/etc/amd.net,dev=0000000b 0 0
>automount(pid1622) /net autofs rw,fd=5,pgrp=1622,minproto=2,maxproto=4 0
>0
>
>Here's what I know:  I'm running Mandrake 9.0 kernel 2.4.19-16mdk.  In
>the "services" configuration (which sets up what daemons and other
>services start at boot automatically etc...) I tried to stop netfs and
>nfslock by stopping them and changing their startup to "manual" instead
>of "on boot".  But it didn't take.  In the syslog logfile it says that
>amd was the last process to mount /net.  The only reason I installed
>these services is because I am planning on putting this machine on a
>home network with a WinXP box.  Could it be having problems because
>there is nothing to find in the /net folder?  Since it is not listed in
>/etc/fstab is there any way to get rid of it?




--
-------------------------------------------"Never tell me the odds!"--------
Ray Olszewski					-- Han Solo
Palo Alto, California, USA			  ray@comarre.com
-------------------------------------------------------------------------------

-
To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.linux-learn.org/faqs