[Openstack] [Swift] Unexplained 404s

Shrinand Javadekar shrinand at maginatics.com
Tue May 24 18:59:42 UTC 2016


Thanks for the explanations everyone!

I found the object written into the second handoff node.

1. So when the replicator catches up, it will move the object back to
the correct location. Is that right?
2. Is there a way to disable handoffs?

-Shri


On Tue, May 24, 2016 at 3:20 AM, Mark Kirkwood
<mark.kirkwood at catalyst.net.nz> wrote:
> On 24/05/16 11:20, Clay Gerrard wrote:
>>
>>
>> On Mon, May 23, 2016 at 1:49 PM, Shrinand Javadekar
>> <shrinand at maginatics.com <mailto:shrinand at maginatics.com>> wrote:
>>
>>
>>     If objects are placed on different devices than the computed ones,
>>     they will be unavailable until the replication places them at the
>>     correct location.
>>
>> This part doesn't sound quite right to me, but the transaction logs will
>> tell.
>>
>> My guess is that if the nodes the data is getting written too (primary or
>> handoff) are so overloaded they're getting timed out - it's possible after
>> request_node_count checks on to the backend storage nodes the response still
>> ends up looking like a 404 because none of the nodes that were able to
>> respond had the data.
>>
>>
>
> Agreed, I didn't determine the cause definitively, was guessing too! Your
> explanation sounds more plausible - and yeah, his logs will hopefully shed
> some light!
>
> (I might have a closer look at the slow system here that gets 404's and try
> to see why exactly they are happening - could be a different problem).
>
> Cheers
>
> Mark




More information about the Openstack mailing list