With this interdiff, LGTM. On Tue, 13 Oct 2015 at 14:21 Klaus Aehlig <[email protected]> wrote:
> > Rest LGTM, thanks > > Based on your comments, I propose the following interdiff. > > > commit 57bc7a30b21e4fca3c6fb27d121da0a3f5886500 > Author: Klaus Aehlig <[email protected]> > Date: Tue Oct 13 12:53:54 2015 +0200 > > Interdiff > > diff --git a/doc/design-n-m-redundancy.rst b/doc/design-n-m-redundancy.rst > index 696bd5e..4536f4c 100644 > --- a/doc/design-n-m-redundancy.rst > +++ b/doc/design-n-m-redundancy.rst > @@ -12,7 +12,10 @@ Current state and shortcomings > ============================== > > Ganeti keeps the cluster N+1 redundant, also taking into account > -:doc:`design-shared-storage-redundancy`. However, e.g., for planning > +:doc:`design-shared-storage-redundancy`. In other words, Ganeti > +tries to keep the cluster in a state, where after failure of a single > +node, no matter which one, all instances can be started immediately. > +However, e.g., for planning > maintenance, it is sometimes desirable to know from how many node > losses the cluster can recover from. This is also useful information, > when operating big clusters and expecting long times for hardware repair. > @@ -28,8 +31,11 @@ The intuitive meaning of an N+M redundant cluster is > that M nodes can > fail without instances being lost. However, when DRBD is used, already > failure of 2 nodes can cause complete loss of an instance. Therefore, the > best we can hope for, is to be able to recover from M sequential failures. > +This intuition that a cluster is N+M redundant, if M nodes can fail > one-by-one, > +leaving enough time for a rebalance in between, without losing instances, > is > +formalized in the next definition. > > -Definition of M+M redundancy > +Definition of N+M redundancy > ---------------------------- > > We keep the definition of :doc:`design-shared-storage-redundancy`. > Moreover, > > > -- > Klaus Aehlig > Google Germany GmbH, Dienerstr. 12, 80331 Muenchen > Registergericht und -nummer: Hamburg, HRB 86891 > Sitz der Gesellschaft: Hamburg > Geschaeftsfuehrer: Matthew Scott Sucherman, Paul Terence Manicle > -- Helga Velroyen Software Engineer [email protected] Google Germany GmbH Dienerstraße 12 80331 München Geschäftsführer: Matthew Scott Sucherman, Paul Terence Manicle Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg Diese E-Mail ist vertraulich. Wenn Sie nicht der richtige Adressat sind, leiten Sie diese bitte nicht weiter, informieren Sie den Absender und löschen Sie die E-Mail und alle Anhänge. Vielen Dank. This e-mail is confidential. If you are not the right addressee please do not forward it, please inform the sender, and please erase this e-mail including any attachments. Thanks.
