Re: HA for Xen

[Jean-Yves Migeon <jeanyves.migeon%free.fr@localhost>]

On 03.10.2010 14:18, River Tarnell wrote:
> Jean-Yves Migeon:
>> What is your intent? Have SCSI disks managed by dom0 (with FC), and
>> export them to domUs through a xen block interface?
> 
> Yes.  I also want automatic failover in case of node failure (which is the 
> reason for using FC -- I understand on Linux DRBD can achieve the same thing, 
> but I'm rather wary of that solution).
>
> I looked at Linux-HA heartbeat, which seems to support this, but it still 
> requires kernel support (e.g. for SCSI-3 PGR, and to panic the system on 
> reservation failure, for I/O fencing) which doesn't seem to exist in NetBSD.  
> I 
> wouldn't mind implementing this, but I'm not sure how much work is actually 
> required.

I don't either, sorry.

> I don't necessarily need NetBSD to be the dom0.  I did look at Citrix 
> XenServer, which does everything I need, but it can't run NetBSD as a PV 
> guest because of [0].  I imagine it would work as an HVM guest, but I'd 
> rather 
> avoid that (my experience of running FreeBSD as an HVM guest is that 
> performance is very poor -- I don't know if NetBSD would be any better there).

Yeah, for [0], it is a wip; see

http://mail-index.netbsd.org/port-xen/2010/10/01/msg006283.html

Yes, HVM is rather poor regarding I/O, unless you have support for PV
drivers inside the HVM domain.

> Perhaps a standard Linux system (CentOS?) would be the best solution, with 
> NetBSD as the domU.
>
> What I am specifically trying to avoid is using Linux as the domU
operating
> system.  We don't have any Linux here, and I'm not keen on adding it just for 
> this.

Same for Solaris?

What about fs like glusterfs? I think it can provide failover, but I
would advise to ask Emmanuel (manu@) for more details first. It
might/might not do what you want.

-- 
Jean-Yves Migeon
jeanyves.migeon%free.fr@localhost