Le 26/08/2016 à 12:33, InterNetX - Juergen Gotteswinter a écrit :
Am 25.08.2016 um 15:53 schrieb Yaniv Kaul:
On Wed, Aug 24, 2016 at 6:15 PM, InterNetX - Juergen Gotteswinter <juergen.gotteswinter@internetx.com <mailto:juergen.gotteswinter@internetx.com>> wrote:
iSCSI & Ovirt is an awful combination, no matter if multipathed or bonded. its always gambling how long it will work, and when it fails why did it fail.
I disagree. In most cases, it's actually a lower layer issues. In most cases, btw, it's because multipathing was not configured (or not configured correctly).
experience tells me it is like is said, this was something i have seen from 3.0 up to 3.6. Ovirt, and - suprprise - RHEV. Both act the same way. I am absolutly aware of Multpath Configurations, iSCSI Multipathing is very widespread in use in our DC. But such problems are an excluse Ovirt/RHEV Feature.
its supersensitive to latency, and superfast with setting an host to inactive because the engine thinks something is wrong with it. in most cases there was no real reason for.
Did you open bugs for those issues? I'm not aware of 'no real reason' issues.
Support Tickets for Rhev Installation, after Support (even after massive escalation requests) kept telling me the same again and again i gave up and we dropped the RHEV Subscriptions to Migrate the VMS to a different Plattform Solution (still iSCSI Backend). Problems gone.
we had this in several different hardware combinations, self built filers up on FreeBSD/Illumos & ZFS, Equallogic SAN, Nexenta Filer
Been there, done that, wont do again.
We've had good success and reliability with most enterprise level storage, such as EMC, NetApp, Dell filers. When properly configured, of course. Y.
Dell Equallogic? Cant really believe since Ovirt / Rhev and the Equallogic Network Configuration wont play nice together (EQL wants all Interfaces in the same Subnet). And they only work like expected when there Hit Kit Driverpackage is installed. Without Path Failover is like russian Roulette. But Ovirt hates the Hit Kit, so this Combo ends up in a huge mess, because Ovirt does changes to iSCSI, as well as the Hit Kit -> Kaboom. Host not available.
There are several KB Articles in the RHN, without real Solution.
I'm working with Dell, EMC and EQL for 7 years, and with oVirt for 4 years, and I must recognize that what Juergen said is true : HIT is not compatible with the way oVirt is using iSCSI (or the other way round). What he says about LVM is also true. I still love oVirt, and won't quit. I'm just very patient and hoping my BZ and RFE get fixed. -- Nicolas ECARNOT