Open Stack

Hi tobias

yes, I tested today as well. With DiskFilter removed from the nova
default scheduling, one can still do a nova live-migration, no issues
so far experienced.

I think the nova-scheduler.log may throw a warning if you provision a
number of flavors and the total image disk size for all instances is
greater than / on the compute node, the the there may be a warning at
least with the DiskFilter enabled, have you seen any warnings or
errors in logs with DiskFilter removed related to scheduling? thx will



On Thu, Aug 18, 2016 at 2:40 PM, Tobias Urdin <tobias.urdin at crystone.com> wrote:
> Hello William,
>
> We are booting our instances from Cinder volumes over ISCSI with
> multipath and can perform live migration just fine.
>
> The things we have changed:
>
> nova.conf on compute nodes
>
> [libvirt]
> virt_type=kvm
> inject_password=true
> inject_key=true
> inject_partition=-1
> live_migration_flag=VIR_MIGRATE_UNDEFINE_SOURCE,VIR_MIGRATE_PEER2PEER,VIR_MIGRATE_LIVE
> iscsi_use_multipath = True
>
> The live_migration_flag is deprecated and will be removed in next
> release I think, but we are running Liberty stable and haven't upgraded yet.
>
> Also we had issues with live migration and multipath volumes turning
> into a failed state. Changing the failback and retry settings for
> multipathd solved it (see https://bugs.launchpad.net/nova/+bug/1525802)
>
> multipath.conf on compute nodes
>
> defaults {
>         failback immediate
>         no_path_retry 0
> }
>
> Best regards
>
> Tobias
>
>
> On 08/15/2016 05:15 PM, William Josefsson wrote:
>> yes thx tobias, did you try live-migration after this change? I will
>> try on my end too and share whether it worked with the DiskFilter
>> disabled or not. thx will
>>
>> On Mon, Aug 15, 2016 at 4:22 PM, Tobias Urdin <tobias.urdin at crystone.com> wrote:
>>> Hello,
>>>
>>> We are having this issue in production and I have since pushed for a fix
>>> for this.
>>>
>>> We solved it by removing the DiskFilter filter, ignore any RT data from
>>> nova and seen in horizon and keep close monitoring on our block storage
>>> usage.
>>>
>>> nova.conf:
>>>
>>> #scheduler_default_filters = RetryFilter, AvailabilityZoneFilter,
>>> RamFilter, DiskFilter, ComputeFilter, ComputeCapabilitiesFilter,
>>> ImagePropertiesFilter, ServerGroupAntiAffinityFilter,
>>> ServerGroupAffinityFilter
>>> scheduler_default_filters = RetryFilter, AvailabilityZoneFilter,
>>> RamFilter, ComputeFilter, ComputeCapabilitiesFilter,
>>> ImagePropertiesFilter, ServerGroupAntiAffinityFilter,
>>> ServerGroupAffinityFilter
>>>
>>> Default options is the one commented out, the other one has DiskFilter
>>> removed.
>>>
>>> We haven't had any issues after removing the DiskFilter.
>>>
>>>
>>> Best regards
>>>
>>>
>>> On 08/15/2016 10:17 AM, Kostiantyn.Volenbovskyi at swisscom.com wrote:
>>>> Hi,
>>>>
>>>> Just to add that this bug was recently brought up in openstack-dev [1]
>>>>
>>>> it sounds that you are waiting for fix via [2] or, probably more likely [3]
>>>> Disabling DiskFilter sounds like OK workaround in case your VMs are never booted from image in your OpenStack Region(s).
>>>> But if I understand the fault - the migrate/resize/live migrate/rebuild/evacuate will not work because
>>>> . assuming that on target Compute Host you don't have local disk - and your flavor has more than 0 GB for root and/or ephemeral disk
>>>> -it would fail.
>>>>
>>>> So I would say that setting your root disk space to '0' in the flavor might be a better workaround
>>>>
>>>> BR,
>>>> Konstantin
>>>> [1] http://lists.openstack.org/pipermail/openstack-dev/2016-August/101566.html
>>>> [2] https://review.openstack.org/#/c/200870/
>>>> [3] https://review.openstack.org/#/c/355091/
>>>>
>>>>
>>>>> -----Original Message-----
>>>>> From: William Josefsson [mailto:william.josefson at gmail.com]
>>>>> Sent: Sunday, August 14, 2016 5:47 PM
>>>>> To: openstack-operators at lists.openstack.org
>>>>> Subject: [Openstack-operators] DiskFilter Disabled - No valid host was found
>>>>>
>>>>> Hello, I got Error, no valid host was found while trying to provision and I could in
>>>>> nova-scheduler.log see that the DiskFilter failed to find a compute host. My OS is
>>>>> CentOS7/ running Liberty.
>>>>>
>>>>> If I'm not mistaken, it is a bug that DiskFilter checks space available on compute-
>>>>> host / partition even when I'm using iSCSI and RBD backends. The / is no way
>>>>> near full.
>>>>> https://bugs.launchpad.net/nova/+bug/1358566
>>>>>
>>>>> Can anyone confirm whether it is fine to disable DiskFilter if I'm using iSCSI and
>>>>> RBD backend or would anything else brake? thx will
>>>>>
>>>>> _______________________________________________
>>>>> OpenStack-operators mailing list
>>>>> OpenStack-operators at lists.openstack.org
>>>>> http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-operators
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>>>> OpenStack-operators at lists.openstack.org
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>>>>
>