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<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>The current locking is quite simple. Simply connect to the
master and exec ‘pvesm lock <STOREID>’<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'># ssh -o 'BatchMode=yes' <IP_OF_MASTER> /usr/sbin/pvesm
lock <STOREID><o:p></o:p></span></p>
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color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>But you can only make a shapshot on the host which runs the VM –
LVM snapshots are not cluster aware!<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>- Dietmar<o:p></o:p></span></p>
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color:#1F497D'><o:p> </o:p></span></p>
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<p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:
"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'> pve-user-bounces@pve.proxmox.com
[mailto:pve-user-bounces@pve.proxmox.com] <b>On Behalf Of </b>Hugh Saunders<br>
<b>Sent:</b> Donnerstag, 28. Jänner 2010 13:02<br>
<b>To:</b> pve-user@pve.proxmox.com<br>
<b>Subject:</b> Re: [PVE-User] lvm+iscsi<o:p></o:p></span></p>
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<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Hi Martin, <br>
<br>
On Wed, Jan 27, 2010 at 1:38 PM, Martin Maurer <<a
href="mailto:martin@proxmox.com">martin@proxmox.com</a>> wrote:<br>
<br>
>> 2) How does proxmox ensure the use of LVM is cluster safe?<br>
>> Eg if I have an iSCSI lun that is connected to both hosts, and each VM<br>
>> uses a separate LV, thats fine, but how does proxmox ensure that:<br>
>> a) The same LV is not mounted on both host machines at once<br>
>> b) That only one host attempts to update the LVM meta-data at a time?<br>
>> (Eg create a new lv/snapshot)<br>
><br>
> We implemented our own locking mechanism.<br>
<br>
Good to hear that. <br>
<br>
One more question about this:<br>
<br>
I'd like to have another machine connect to the LUN+VG in order to take LVM
snapshots of each LV, and back them up. This machine would not be hosting any
virtual machines. Is it possible to run the proxmox locking mechanism on the machine
thats taking the backups, without running a full install of proxmox? The backup
box would be debian/ubuntu based. <br>
<br>
Thanks, <br>
<br>
-- <br>
Hugh Saunders <o:p></o:p></p>
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