Re: [ceph-users] What is the meaning of size and min_size for erasure-coded pools?

I still don't understand why I get any clean PGs in the erasure-coded pool, when with two OSDs down there is no more redundancy, and therefore all PGs should be undersized (or so I think). I repeated the experiment by bringing two remaining OSDs online, and then killing them, and got results

Re: [ceph-users] What is the meaning of size and min_size for erasure-coded pools?

On Wed, May 9, 2018 at 4:37 PM, Maciej Puzio wrote: > My setup consists of two pools on 5 OSDs, and is intended for cephfs: > 1. erasure-coded data pool: k=3, m=2, size=5, min_size=3 (originally > 4), number of PGs=128 > 2. replicated metadata pool: size=3, min_size=2, number

Re: [ceph-users] What is the meaning of size and min_size for erasure-coded pools?

My setup consists of two pools on 5 OSDs, and is intended for cephfs: 1. erasure-coded data pool: k=3, m=2, size=5, min_size=3 (originally 4), number of PGs=128 2. replicated metadata pool: size=3, min_size=2, number of PGs=100 When all OSDs were online, all PGs from both pools has status

Re: [ceph-users] What is the meaning of size and min_size for erasure-coded pools?

On Tue, May 8, 2018 at 2:16 PM Maciej Puzio wrote: > Thank you everyone for your replies. However, I feel that at least > part of the discussion deviated from the topic of my original post. As > I wrote before, I am dealing with a toy cluster, whose purpose is not > to

Re: [ceph-users] What is the meaning of size and min_size for erasure-coded pools?

Thank you everyone for your replies. However, I feel that at least part of the discussion deviated from the topic of my original post. As I wrote before, I am dealing with a toy cluster, whose purpose is not to provide a resilient storage, but to evaluate ceph and its behavior in the event of a

Re: [ceph-users] What is the meaning of size and min_size for erasure-coded pools?

On Tue, May 8, 2018 at 12:07 PM, Dan van der Ster wrote: > On Tue, May 8, 2018 at 7:35 PM, Vasu Kulkarni wrote: >> On Mon, May 7, 2018 at 2:26 PM, Maciej Puzio wrote: >>> I am an admin in a research lab looking for a cluster storage

Re: [ceph-users] What is the meaning of size and min_size for erasure-coded pools?

On Tue, May 8, 2018 at 7:35 PM, Vasu Kulkarni wrote: > On Mon, May 7, 2018 at 2:26 PM, Maciej Puzio wrote: >> I am an admin in a research lab looking for a cluster storage >> solution, and a newbie to ceph. I have setup a mini toy cluster on >> some VMs,

Re: [ceph-users] What is the meaning of size and min_size for erasure-coded pools?

On Mon, May 7, 2018 at 2:26 PM, Maciej Puzio wrote: > I am an admin in a research lab looking for a cluster storage > solution, and a newbie to ceph. I have setup a mini toy cluster on > some VMs, to familiarize myself with ceph and to test failure > scenarios. I am using ceph

Re: [ceph-users] What is the meaning of size and min_size for erasure-coded pools?

You talked about "using default settings wherever possible"... Well, Ceph's default settings everywhere they exist, is to not allow you to write while you don't have at least 1 more copy that you can lose without data loss. If your bosses require you to be able to lose 2 servers and still serve

Re: [ceph-users] What is the meaning of size and min_size for erasure-coded pools?

2018-05-08 1:46 GMT+02:00 Maciej Puzio : > Paul, many thanks for your reply. > Thinking about it, I can't decide if I'd prefer to operate the storage > server without redundancy, or have it automatically force a downtime, > subjecting me to a rage of my users and my boss. >

Re: [ceph-users] What is the meaning of size and min_size for erasure-coded pools?

It's a very bad idea to accept data if you can't guarantee that it will be stored in way that tolerates a disk outage without data loss. Just don't. Increase the number of coding chunks to 3 if you want to withstand two simultaneous disk failures without impacting availability. Paul

Re: [ceph-users] What is the meaning of size and min_size for erasure-coded pools?

Paul, many thanks for your reply. Thinking about it, I can't decide if I'd prefer to operate the storage server without redundancy, or have it automatically force a downtime, subjecting me to a rage of my users and my boss. But I think that the typical expectation is that system serves the data

Re: [ceph-users] What is the meaning of size and min_size for erasure-coded pools?

The docs seem wrong here. min_size is available for erasure coded pools and works like you'd expect it to work. Still, it's not a good idea to reduce it to the number of data chunks. Paul 2018-05-07 23:26 GMT+02:00 Maciej Puzio : > I am an admin in a research lab looking