[Xen-users] as promised description of my XEN HA setup

[Bart Coninckx <bart.coninckx@xxxxxxxxxx>]

Hi all,

In threads posted by I believe Jonathan Tripley I promised to post my new XEN 
HA setup. Hope it can be of some use to some people. 

In this particular case I'm forced to use SLES 10SP3 with XEN 3.2, which 
excludes the possibility of using things like cLVM (which I don't think I need 
anyway).

So:

Storage:
I use two HP ML370 G5 machines with DRBD and heartbeat on them. They are 
linked by two Gigabit bonded NICs for syncing. They offer IET across two other 
NICs with IPs in different segments. DRBD is on top of LVM and LVM is again on 
top of DRBD to be able to create a LV for each DomU. 

Network:
switches are HP Procurve 1810. Not the fastest switches, but also not the most 
expensive ones. Will report later on if they can handle it all.

Hypervisors:
different machines, but for the moment all having 4 NICs. One NIC is for the 
trusted LAN, two are used for iSCSI initiating. One for DomUs in the DMZ. I 
use multipathing on top of the iSCSI paths for redundancy and supposedbly 
extra speed (his hasn't been proven yet). The paths run over different 
switches for redundancy.

DomUs:
Currently HVMs. Will have about 10 in the end. They use phy: devices pointing 
to the multipath devices. config files are synced across the Hypervisors (no 
network storage for avoiding SPOF). 

HA:
(to do) Pacemaker will take care of monitoring DomUs and failing them over.

Backup:
It seems the only save way to backup DomUs is by shutting them down, so what I 
do is make sure the storage servers can ssh to the Hypervisors with public key 
auth. They will shut down the guests, create a snapshot volume of the relevant 
LV for that particular machine (a script finds out where it is running), start 
the guests again and dd the snapshot  to a file server over ssh. Next the 
snapshot is deleted. 


There you go, hope this can inspire people.  ;-)

B.




_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users