Hello,
Am 26.03.2010 um 16:53 Uhr schrieb Wiebe Cazemier <halfgaar@xxxxxxx>:
> On Friday 26 March 2010 16:36, Markus Hochholdinger wrote:
> >> iSCSI is nearly ubiquitous among commercial SAN products these days.
> >
> > and it's also possible to create a completly open source SAN with a linux
> > host. Just use lvm2 with iscsi enterprise target.
> >
> > I've done this and i use the storage hosts also as xen hosts. I've all
> > the nice features, live migration, storage redundancy with software raid1
> > inside the domUs, backup scripts for the whole volume group, can scale
> > from 2 to n hosts, ...
> I will look into that.
> A question though: "software raid1 inside the domU's"? Why inside the
> domU's? I would have the storage on a RAID+LVM, but not inside the domU's.
inside the domU you will never have a split brain situation for the storage!
And you can grow the filesystem online without the need to reboot.
> Can you elaborate a bit more about your storage hosts? I was planning to
> have two hosts: a primary host with a failover one. The failover can take
> over by bringing up a virtual network interface with the same IP. Their
> data would be kept up-to-date by DRBD.
There you go with your problems: primary host, failover, bring up network... A
lot of things that can fail! DRBD needs heartbeat, HA-Cluster, ... These are
all problems i don't have!
> But, I haven't figured out how I am going to let the xen hosts access the
> data.
Yeah, you see! You could do drbd (raid1 outside domU). Big problem is if you
mirror the whole volume group, but mirroring each logical volume is also a
lot of effort. So you should mirror each logical volume and access this
directly on each host. So you're limited to 2 hosts. Additionally you could
export the drbd devices over iscsi, but there, again, you get into split
brain situations...
--
Gruß
\|/
eMHa (o o)
------------------------------------------------------oOO--U--OOo--
Markus Hochholdinger
e-mail mailto:Markus@xxxxxxxxxxxxxxxxx .oooO
www http://www.hochholdinger.net ( ) Oooo.
------------------------------------------------------\ (----( )-
Ich will die Welt verändern, \_) ) /
aber Gott gibt mir den Quelltext nicht! (_/
signature.asc
Description: This is a digitally signed message part.
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users
|
Home