[Drbd-dev] Summary (3rd try)

[Drbd-dev] Summary (3rd try)

[Philipp Reisner]

Hi,

I tried to incooperate the comments of LMB and LGE. Please review:

after-pri-pri-now-sec-sec = 
 disconnect     No automatic resynchronisation gets performed. One
                node should drop its net-conf (preferable the
                node that would become sync-target)
                DEFAULT.
 ass-older      Auto sync source is the oder primary (curr.behaviour i.t.s.)
 ass-younger    Auto sync source is the younger primary
 ass-furthest   Auto sync source is the node that did more modifications
 ass-NODENAME   Auto sync source is the named node 


pri-sees-sec-with-higher-gc =
 disconnect	(current behaviour)
 ass-primary	Auto sync source is the current primary
 panic		The current primary panics. The node with the
		higher gc should take over.


Notes:
1) The disconnect actions cause the sync-target or the secondary
   node to go into StandAllone state.
2) If two nodes in primary state try to connect one of them goes
   into StandAllone state (=curr. behaviour)
3) As soon as the decission is takes the sync-target addopts the
   GC of the sync source. 
   [ The whole algorith would also work if both would reset their 
     GCs to <0,0,0...> after the decission, but since we also
     use the GC to tag the bitmap it is better the current way ]

Is this better than try2 ?
Should we improve the naming ? "ass" might not be the best choice.
Do you think that the naming is constent ?
Is it still ambiguous ?

-Philipp
-- 
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: LINBIT Information Technologies GmbH          Fax +43-1-8178292-82 :
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Re: [Drbd-dev] Summary (3rd try)

[Lars Marowsky-Bree]

On 2004-08-25T17:13:45,
   Philipp Reisner <philipp.reisner@linbit.com> said:

> Hi,
> 
> I tried to incooperate the comments of LMB and LGE. Please review:
> 
> after-pri-pri-now-sec-sec = 

I wish I had a better name here ;-)

>  disconnect     No automatic resynchronisation gets performed. One
>                 node should drop its net-conf (preferable the
>                 node that would become sync-target)
>                 DEFAULT.

Hmmm. Should they drop the netconf, or should instead the first node to
be elected primary become the SyncSource implicitly?

>  ass-older      Auto sync source is the oder primary (curr.behaviour i.t.s.)
>  ass-younger    Auto sync source is the younger primary

I'm a bit concerned about the older vs younger distinction. "before" and
"after" may be slightly better at conveying what you mean.

>  ass-furthest   Auto sync source is the node that did more modifications
>  ass-NODENAME   Auto sync source is the named node 

> pri-sees-sec-with-higher-gc =
>  disconnect	(current behaviour)
>  ass-primary	Auto sync source is the current primary
>  panic		The current primary panics. The node with the
> 		higher gc should take over.

Seems ok.

> Notes:
> 1) The disconnect actions cause the sync-target or the secondary
>    node to go into StandAllone state.
> 2) If two nodes in primary state try to connect one of them goes
>    into StandAllone state (=curr. behaviour)

This is not quite symmetric, which means special cases ;-) Shouldn't
they either refuse to connect, or both drop to StandAlone?

> 3) As soon as the decission is takes the sync-target addopts the
>    GC of the sync source. 
>    [ The whole algorith would also work if both would reset their 
>      GCs to <0,0,0...> after the decission, but since we also
>      use the GC to tag the bitmap it is better the current way ]

Ok.

> Is this better than try2 ?
> Should we improve the naming ? "ass" might not be the best choice.

auto-sync-from-

> Do you think that the naming is constent ?
> Is it still ambiguous ?

I hope it's not, but the other Lars is better at spotting
inconsistencies than I am ;-)


Sincerely,
    Lars Marowsky-Brée <lmb@suse.de>

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