ISCSI with multiple nodes

[vince_122]

Hi,

I'm trying to set-up an ISCSI server which exports some LUN created over Fibre Channel.
This server exports his /dev/sdb over ISCSI.

My question is :

Can I connect all my Proxmox nodes on the same ISCSI LUN (=the same FC LUN) ? I read some problems about concurrent access with ISCSI, but as each node access to her own directory (corresponding to the CT's directories), is it possible to do that ?

Thanks for all !
Vince.

 

[cmassoglia]

When you use iscsi over any connection type you must use with LVM. With this, you can attach the iscsi in each proxmox node and use it with problem about concurrent access

Each VM (KVM) must use raw disk, so when a node start a vm only that node activate the logical volume in lvm for that vm. In this way never two nodes access at the same time to a same logical volume, this avoid corruption.

We actually have 2 nodes connected to a iscsi lun, using LVM and we have not problems with concurrent access or corrupted data.

Sorry my bad english.

kind regards,

 

[thesubmitter]

What you can do with ISCSI and Proxmox changes completely between VZ and KVM. KVM will let you share a single LUN with LVM on top of it but for VZ Containers you can't do much more than create a LUN and mount is a local FileSystem in your host. You also won't be able to share it. However what I am considering is:

NFS --> FS --> ISCSI

so the server will access its own local NFS export for most of the images and once in a while work with containers on another machine....

 

[vince_122]

Thanks for your answers.

Thanks thesubmitter for your help, this is what I was thinking for ^^
Here is what I'm going to do :


3 LUNS -> FC -> PortalHost -> ISCSI -> LUN1 -> Node 1
......................................-> ISCSI -> LUN2 -> Node 2
......................................-> ISCSI -> LUN3 -> Node 3

Thanks for all again !
Vince.