[ovirt-users] storage redundancy in Ovirt

Mon Apr 17 05:24:48 UTC 2017

But actually, it didn't work well. After main SPM host went down I see this

2017-04-17 05:23:15,554Z ERROR
[org.ovirt.engine.core.vdsbroker.irsbroker.IrsProxy]
(DefaultQuartzScheduler5) [4dcc033d-26bf-49bb-bfaa-03a970dbbec1] SPM Init:
could not find reported vds or not up - pool: 'STG' vds_spm_id: '1'
2017-04-17 05:23:15,567Z INFO
 [org.ovirt.engine.core.vdsbroker.irsbroker.IrsProxy]
(DefaultQuartzScheduler5) [4dcc033d-26bf-49bb-bfaa-03a970dbbec1] SPM
selection - vds seems as spm 'tank5'
2017-04-17 05:23:15,567Z WARN
 [org.ovirt.engine.core.vdsbroker.irsbroker.IrsProxy]
(DefaultQuartzScheduler5) [4dcc033d-26bf-49bb-bfaa-03a970dbbec1] spm vds is
non responsive, stopping spm selection.

So that means only if BMC is up it's possible to automatically switch  SPM
host?

Thanks

On Sun, Apr 16, 2017 at 8:29 PM, Konstantin Raskoshnyi <konrasko at gmail.com>
wrote:

> Oh, fence agent works fine if I select ilo4,
> Thank you for your help!
>
> On Sun, Apr 16, 2017 at 8:22 PM Dan Yasny <dyasny at gmail.com> wrote:
>
>> On Sun, Apr 16, 2017 at 11:19 PM, Konstantin Raskoshnyi <
>> konrasko at gmail.com> wrote:
>>
>>> Makes sense.
>>> I was trying to set it up, but doesn't work with our staging hardware.
>>> We have old ilo100, I'll try again.
>>> Thanks!
>>>
>>>
>> It is absolutely necessary for any HA to work properly. There's of course
>> the "confirm host has been shutdown" option, which serves as an override
>> for the fence command, but it's manual
>>
>>
>>> On Sun, Apr 16, 2017 at 8:18 PM Dan Yasny <dyasny at gmail.com> wrote:
>>>
>>>> On Sun, Apr 16, 2017 at 11:15 PM, Konstantin Raskoshnyi <
>>>> konrasko at gmail.com> wrote:
>>>>
>>>>> Fence agent under each node?
>>>>>
>>>>
>>>> When you configure a host, there's the power management tab, where you
>>>> need to enter the bmc details for the host. If you don't have fencing
>>>> enabled, how do you expect the system to make sure a host running a service
>>>> is actually down (and it is safe to start HA services elsewhere), and not,
>>>> for example, just unreachable by the engine? How do you avoid a splitbraid
>>>> -> SBA ?
>>>>
>>>>
>>>>>
>>>>> On Sun, Apr 16, 2017 at 8:14 PM Dan Yasny <dyasny at gmail.com> wrote:
>>>>>
>>>>>> On Sun, Apr 16, 2017 at 11:13 PM, Konstantin Raskoshnyi <
>>>>>> konrasko at gmail.com> wrote:
>>>>>>
>>>>>>> "Corner cases"?
>>>>>>> I tried to simulate crash of SPM server and ovirt kept trying to
>>>>>>> reistablished connection to the failed node.
>>>>>>>
>>>>>>
>>>>>> Did you configure fencing?
>>>>>>
>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> On Sun, Apr 16, 2017 at 8:10 PM Dan Yasny <dyasny at gmail.com> wrote:
>>>>>>>
>>>>>>>> On Sun, Apr 16, 2017 at 7:29 AM, Nir Soffer <nsoffer at redhat.com>
>>>>>>>> wrote:
>>>>>>>>
>>>>>>>>> On Sun, Apr 16, 2017 at 2:05 PM Dan Yasny <dyasny at redhat.com>
>>>>>>>>> wrote:
>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> On Apr 16, 2017 7:01 AM, "Nir Soffer" <nsoffer at redhat.com> wrote:
>>>>>>>>>>
>>>>>>>>>> On Sun, Apr 16, 2017 at 4:17 AM Dan Yasny <dyasny at gmail.com>
>>>>>>>>>> wrote:
>>>>>>>>>>
>>>>>>>>>>> When you set up a storage domain, you need to specify a host to
>>>>>>>>>>> perform the initial storage operations, but once the SD is defined, it's
>>>>>>>>>>> details are in the engine database, and all the hosts get connected to it
>>>>>>>>>>> directly. If the first host you used to define the SD goes down, all other
>>>>>>>>>>> hosts will still remain connected and work. SPM is an HA service, and if
>>>>>>>>>>> the current SPM host goes down, SPM gets started on another host in the DC.
>>>>>>>>>>> In short, unless your actual NFS exporting host goes down, there is no
>>>>>>>>>>> outage.
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> There is no storage outage, but if you shutdown the spm host, the
>>>>>>>>>> spm host
>>>>>>>>>> will not move to a new host until the spm host is online again,
>>>>>>>>>> or you confirm
>>>>>>>>>> manually that the spm host was rebooted.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> In a properly configured setup the SBA should take care of that.
>>>>>>>>>> That's the whole point of HA services
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>> In some cases like power loss or hardware failure, there is no way
>>>>>>>>> to start
>>>>>>>>> the spm host, and the system cannot recover automatically.
>>>>>>>>>
>>>>>>>>
>>>>>>>> There are always corner cases, no doubt. But in a normal situation.
>>>>>>>> where an SPM host goes down because of a hardware failure, it gets fenced,
>>>>>>>> other hosts contend for SPM and start it. No surprises there.
>>>>>>>>
>>>>>>>>
>>>>>>>>>
>>>>>>>>> Nir
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> Nir
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> On Sat, Apr 15, 2017 at 1:53 PM, Konstantin Raskoshnyi <
>>>>>>>>>>> konrasko at gmail.com> wrote:
>>>>>>>>>>>
>>>>>>>>>>>> Hi Fernando,
>>>>>>>>>>>> I see each host has direct connection nfs mount, but yes, if
>>>>>>>>>>>> main host to which I connected nfs storage going down the storage becomes
>>>>>>>>>>>> unavailable and all vms are down
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> On Sat, Apr 15, 2017 at 10:37 AM FERNANDO FREDIANI <
>>>>>>>>>>>> fernando.frediani at upx.com> wrote:
>>>>>>>>>>>>
>>>>>>>>>>>>> Hello Konstantin.
>>>>>>>>>>>>>
>>>>>>>>>>>>> That doesn`t make much sense make a whole cluster depend on a
>>>>>>>>>>>>> single host. From what I know any host talk directly to NFS Storage Array
>>>>>>>>>>>>> or whatever other Shared Storage you have.
>>>>>>>>>>>>> Have you tested that host going down if that affects the other
>>>>>>>>>>>>> with the NFS mounted directlly in a NFS Storage array ?
>>>>>>>>>>>>>
>>>>>>>>>>>>> Fernando
>>>>>>>>>>>>>
>>>>>>>>>>>>> 2017-04-15 12:42 GMT-03:00 Konstantin Raskoshnyi <
>>>>>>>>>>>>> konrasko at gmail.com>:
>>>>>>>>>>>>>
>>>>>>>>>>>>>> In ovirt you have to attach storage through specific host.
>>>>>>>>>>>>>> If host goes down storage is not available.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> On Sat, Apr 15, 2017 at 7:31 AM FERNANDO FREDIANI <
>>>>>>>>>>>>>> fernando.frediani at upx.com> wrote:
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> Well, make it not go through host1 and dedicate a storage
>>>>>>>>>>>>>>> server for running NFS and make both hosts connect to it.
>>>>>>>>>>>>>>> In my view NFS is much easier to manage than any other type
>>>>>>>>>>>>>>> of storage, specially FC and iSCSI and performance is pretty much the same,
>>>>>>>>>>>>>>> so you won`t get better results other than management going to other type.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> Fernando
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> 2017-04-15 5:25 GMT-03:00 Konstantin Raskoshnyi <
>>>>>>>>>>>>>>> konrasko at gmail.com>:
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Hi guys,
>>>>>>>>>>>>>>>> I have one nfs storage,
>>>>>>>>>>>>>>>> it's connected through host1.
>>>>>>>>>>>>>>>> host2 also has access to it, I can easily migrate
>>>>>>>>>>>>>>>> vms between them.
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> The question is - if host1 is down - all infrastructure is
>>>>>>>>>>>>>>>> down, since all traffic goes through host1,
>>>>>>>>>>>>>>>> is there any way in oVirt to use redundant storage?
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Only glusterfs?
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Thanks
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> _______________________________________________
>>>>>>>>>>>>>>>> Users mailing list
>>>>>>>>>>>>>>>> Users at ovirt.org
>>>>>>>>>>>>>>>> http://lists.ovirt.org/mailman/listinfo/users
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>> _______________________________________________
>>>>>>>>>>>> Users mailing list
>>>>>>>>>>>> Users at ovirt.org
>>>>>>>>>>>> http://lists.ovirt.org/mailman/listinfo/users
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>> _______________________________________________
>>>>>>>>>>> Users mailing list
>>>>>>>>>>> Users at ovirt.org
>>>>>>>>>>> http://lists.ovirt.org/mailman/listinfo/users
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> _______________________________________________
>>>>>>>>>> Users mailing list
>>>>>>>>>> Users at ovirt.org
>>>>>>>>>> http://lists.ovirt.org/mailman/listinfo/users
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
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