OpenStack Object Storage (swift)

number of replicas

Asked by Rainer Toebbicke

Hello,

from what I understand the number of replicas for a given object (or even the partition) is specified by swift-ring-builder when the object storage ring is created.

Do I further understand correctly that:

1. modulo disc outages, for a given file (object) this number is constant once the object has been created?

2. the number if the same for all objects stored in that swift instance?

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John Dickinson (notmyname) said : 		#1

Correct. The number of replicas is global for all objects, containers, and accounts.

Assuming no errors in the system, you will only have <replicas> copies in the system. Under certain failure and recovery conditions, you can have from 1 to N copies, when N is the number of zones in the cluster.

--John

On May 2, 2011, at 4:44 AM, Rainer Toebbicke wrote:

> New question #155417 on OpenStack Object Storage (swift):
> https://answers.launchpad.net/swift/+question/155417
>
> Hello,
>
> from what I understand the number of replicas for a given object (or even the partition) is specified by swift-ring-builder when the object storage ring is created.
>
> Do I further understand correctly that:
>
> 1. modulo disc outages, for a given file (object) this number is constant once the object has been created?
>
> 2. the number if the same for all objects stored in that swift instance?
>
> --
> You received this question notification because you are a member of
> Swift Core, which is an answer contact for OpenStack Object Storage
> (swift).

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