[linux-lvm] LVM across network

[linux-lvm] LVM across network

[Marek Jan]

Hello, 
I have simple question. Is it possible run LVM across network ?
For example, first disk on pc1, second on pc3, third on pc3...
I need file system that colecting free space across network onto one 
point.
Thank you, Marek Jan 

Re: [linux-lvm] LVM across network

[Spam]

  Yes.  This is possible with NBD 2.0 and later (earlier nbd tools has
  limitation  of  4GB  per  shared  disk/volume/device).  You  need to
  compile the NBD (Network Block Device) module in the kernel too.

  Then simply run on the server (the machines hosting spare volumes):

    nbd-server  10000 /dev/hdax  (replace 10009 with the port you want
    to use)

  On  the  client  machine  (where  you want to run LVM to collect all
  space;

    nbd-client IP port /dev/nbd/0

  For  each  server  you connect simply change the IP/port and the NBD
  device number. After this you run "vgscan" and "vgchange -ay vg"

  You  should  be warned though. If you loose network connectivity you
  can end up with filesystem damage.


> Hello, 
> I have simple question. Is it possible run LVM across network ?
> For example, first disk on pc1, second on pc3, third on pc3...
> I need file system that colecting free space across network onto one
> point.
> Thank you, Marek Jan 


> _______________________________________________
> linux-lvm mailing list
> linux-lvm@sistina.com
> http://lists.sistina.com/mailman/listinfo/linux-lvm
> read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/

Re: [linux-lvm] LVM across network

[neuron]

quick question about this, been looking for a good solution for this a long time.  Any filesystems that can loose connectivity?  I have a setup where I can't guarantee all the computers will stay stable, but it's only a setup for temporary storage anyway (1gb networks, temporary storage is for rendering files).

> 
>   Yes.  This is possible with NBD 2.0 and later (earlier nbd tools has
>   limitation  of  4GB  per  shared  disk/volume/device).  You  need to
>   compile the NBD (Network Block Device) module in the kernel too.
> 
>   Then simply run on the server (the machines hosting spare volumes):
> 
>     nbd-server  10000 /dev/hdax  (replace 10009 with the port you want
>     to use)
> 
>   On  the  client  machine  (where  you want to run LVM to collect all
>   space;
> 
>     nbd-client IP port /dev/nbd/0
> 
>   For  each  server  you connect simply change the IP/port and the NBD
>   device number. After this you run "vgscan" and "vgchange -ay vg"
> 
>   You  should  be warned though. If you loose network connectivity you
>   can end up with filesystem damage.
> 
> 
> > Hello, 
> > I have simple question. Is it possible run LVM across network ?
> > For example, first disk on pc1, second on pc3, third on pc3...
> > I need file system that colecting free space across network onto one
> > point.
> > Thank you, Marek Jan 
> 
> 
> > _______________________________________________
> > linux-lvm mailing list
> > linux-lvm@sistina.com
> > http://lists.sistina.com/mailman/listinfo/linux-lvm
> > read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
> 
> 
> 

Re: [linux-lvm] LVM across network

[Spam]

  As far as I can tell NBD 2.x is stable. You can setup failovers with
  NBD  if  you  have  more  than  one NIC in the computers. I have not
  tested this myself.

  The  risk  is  that you accidentally disconnect a network cable etc.
  Otherwise  it  is  up  to the stability of each machine to make this
  work in the long run. For temp space this is fine =).

  I  doubt  any  network  filesystem  will  allow  you to disconnect a
  machine  and still be able to operate. NFS etc support a reastart of
  the  machine,  but  you cannot consolidate the distributed diskspace
  into one logical volume.

  Give  NBD  a  try and test what happens if you disconnect a computer
  then reconnect it.

  I  am  using  NBD 2.0 in Gentoo Linux together with LVM and ReiserFS
  without any problems (so far).


> quick question about this, been looking for a good solution for
> this a long time.  Any filesystems that can loose connectivity?  I
> have a setup where I can't guarantee all the computers will stay
> stable, but it's only a setup for temporary storage anyway (1gb
> networks, temporary storage is for rendering files).

>> 
>>   Yes.  This is possible with NBD 2.0 and later (earlier nbd tools has
>>   limitation  of  4GB  per  shared  disk/volume/device).  You  need to
>>   compile the NBD (Network Block Device) module in the kernel too.
>> 
>>   Then simply run on the server (the machines hosting spare volumes):
>> 
>>     nbd-server  10000 /dev/hdax  (replace 10009 with the port you want
>>     to use)
>> 
>>   On  the  client  machine  (where  you want to run LVM to collect all
>>   space;
>> 
>>     nbd-client IP port /dev/nbd/0
>> 
>>   For  each  server  you connect simply change the IP/port and the NBD
>>   device number. After this you run "vgscan" and "vgchange -ay vg"
>> 
>>   You  should  be warned though. If you loose network connectivity you
>>   can end up with filesystem damage.
>> 
>> 
>> > Hello, 
>> > I have simple question. Is it possible run LVM across network ?
>> > For example, first disk on pc1, second on pc3, third on pc3...
>> > I need file system that colecting free space across network onto one
>> > point.
>> > Thank you, Marek Jan 
>> 
>> 
>> > _______________________________________________
>> > linux-lvm mailing list
>> > linux-lvm@sistina.com
>> > http://lists.sistina.com/mailman/listinfo/linux-lvm
>> > read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
>> 
>> 
>> 

> _______________________________________________
> linux-lvm mailing list
> linux-lvm@sistina.com
> http://lists.sistina.com/mailman/listinfo/linux-lvm
> read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/

Re: [linux-lvm] LVM across network

[Rickard Olsson]

Spam wrote:

>   I  doubt  any  network  filesystem  will  allow  you to disconnect a
>   machine  and still be able to operate.

I have been eyeing Coda for a while now and it looks like it does 
exactly that. I'm not sure about the storage requirements, though. It 
appears it may need two full mirrors worth for the replication, but they 
can be spread out over a WAN if need be.

http://www.coda.cs.cmu.edu/index.html



iSCSI RAID, anyone?

http://www.simplesan.com/products/iscsiarrays.htm

    / Rickard Olsson,IT-Konsult/
   / Telefon: +46 70 635 01 42/
  / http://www.webhackande.se/

Re: [linux-lvm] LVM across network

[Dan Sully]

* Rickard Olsson <richie@webhackande.se> shaped the electrons to say...

> >  I  doubt  any  network  filesystem  will  allow  you to disconnect a
> >  machine  and still be able to operate.
> 
> I have been eyeing Coda for a while now and it looks like it does 
> exactly that. I'm not sure about the storage requirements, though. It 
> appears it may need two full mirrors worth for the replication, but they 
> can be spread out over a WAN if need be.
> 
> http://www.coda.cs.cmu.edu/index.html

CODA is really dead. If you want a disconnected filesystem, check out
Intermezzo, which is part of the Linux kernel as well.

> iSCSI RAID, anyone?
> 
> http://www.simplesan.com/products/iscsiarrays.htm

I picked up a NetDisk from Fry's over the past week and attempted to get it
to work. Unfortunately, the only Linux drivers they have right now are beta,
and only for Redhat 8 & 9 at that. Their "admin" tools require Tk (not on a
server!), and appear to be some hacked up version of their own code and net-snmp.

The windows drivers worked a bit better, but would say "Drive has been
disconnected" every so often, when nothing had changed physically.

Nice (and relatively cheap) idea, but their implementation has a way to go.

-D
-- 
It's only after you've lost everything that you're free to do anything.