ibm x3650M2 servers+ QNAP storage for pve cluster use: any known issues/suggestions?

[m.ardito]

Hi, we're considering buying 2 servers with iscsi compatible external storage.
About the servers:
IBM Xseries 3650
Rack - n° 2 x Intel Xeon Quad Core E5520 2,26 Ghz
ServeRaid-BR 10i SAS/SATA Controller
Hard Disk: n° 2 x 73 Gb 15.000rpm SAS -
RAM 20 Gb PC3-10600 CL9 ECC DD3-13 (expandable to 128GB max)
PSU: 2 x 675 W -
Net cards: n° 2 x 10/100/1000 RJ45
Multiburner SATA -

About the iscsi NAS:
Qnap TS-809U
Rack 19" - capacity 12 Tb (8 Hard Disk SATA II da 1,5 Tb / each)

i know a blade would be best, and ibm san too, but this is what we could try to get, at the moment...

Thanks, Marco

 

[tom]

Re: ibm x3650M2 servers+ QNAP storage for pve cluster use: any known issues/suggestio

pls describe your planned usage - what kind of guest do you plan to run? openvz, kvm, both?

storage:
I do not know the qnap in detail (do they have real raid controllers inside or just software raid solution), but if you want reliable iSCSI use a dedicated storage network.

 

[m.ardito]

Re: ibm x3650M2 servers+ QNAP storage for pve cluster use: any known issues/suggestio

pls describe your planned usage - what kind of guest do you plan to run? openvz, kvm, both?.

kvm for sure (win vmachines), but i think both as we have several linuxes...

storage:
I do not know the qnap in detail (do they have real raid controllers inside or just software raid solution), but if you want reliable iSCSI use a dedicated storage network.

Don't know, specs dont' report it, so i guess it could be sw raid, although it is a quite impressive nas unit.
I have filed a request to the producer to know that, i'll let you know. My usual hardware reseller/partner had previous good experience with that unit so i gave them credit...

what could be the downsides of a sw raid solution. if it matters, we think to use pve on top of a debian lenny...

Thanks!

 

[tom]

Re: ibm x3650M2 servers+ QNAP storage for pve cluster use: any known issues/suggestio

kvm for sure (win vmachines), but i think both as we have several linuxes...


Don't know, specs dont' report it, so i guess it could be sw raid, although it is a quite impressive nas unit.
I have filed a request to the producer to know that, i'll let you know. My usual hardware reseller/partner had previous good experience with that unit so i gave them credit...

what could be the downsides of a sw raid solution. if it matters, we think to use pve on top of a debian lenny...

Thanks!

I am not a fan of software raid solutions, mainly because of performance and reliability. how do you protect you hard drive cache on a software raid system? ok, you can disable all caches but this will result in performance issue. but i do not want to discuss this too much in this thread, I just point out that a fast and reliable storage system is very essential for a successful virtualization project and as your other hardware is quite golden you should think of investing a bit more here to get maximum output.

back to the 2 ibm boxes:
if you want OpenVZ (and you will), you need local storage (you cannot use the iSCSI here). so depending on your storage needs the 2 x 72 GB (I suggest raid1) are limiting here. go for the bigger disks, e.g 2 x 300 gb. raid controller: make sure you have BBU unit and write cache, I am not sure if this is already integrated here, in fact I did not know this controller. the rest looks nice, but we never tested and validated IBM server here in our lab.

 

[m.ardito]

Re: ibm x3650M2 servers+ QNAP storage for pve cluster use: any known issues/suggestio

well, we have to experiment, we will start with kvm/iscsi and then consider to buy bigger disks (each server has 12 2,5" slots, with the two 75GB disks, 10 slots will remain free...), as for performance considerations, we are fortunately not in the need of race speeds, here, our main concern is reliability and manageability. we come from vmware server (free edition), both on windows and linux hosts. Our vmdk disks seems to work perfectly in kvm here, but sure will gain speed if converted in qcow or raw format.

sure an IBM ds3200 would have been better, but the qnap is already about 3k eur, and we are told ibm units are far superior, but way more expensive too...

I'll let you (and other forum's users) know.

for now really thanks for your incredible product, spirit and support...

can't wait to have the new servers...

Marco