On 4/17/2013 7:05 PM, Russell Jones wrote:
On 4/17/2013 5:52 PM, Dmitri Pal wrote:
> Slices are not given out by the clients.
> Let me try to illustrate.
> Imagine that your slices are storage containers in a storage facility.
> Each slice has a number.
> You come in and you want to use a container. Which one?
> We then take you name, SSN, eye color, DOB etc. and hash. As a result we
> get a number. This number is the number of your storage container.
> Same here. The part of the SID is the unique identifier that identities
> the domain. The hash of it will always have number X. This number will
> always define which storage container (slice) would be used for your
> domain. There is a chance that some other domain would have the same
> number but the probability is very low.
> No you can configure how big slices are. The bigger the slice the
> smaller the number of the slices. So X might map to a different
> container if you start re-configuring things and reducing the width of
> the slices.
By "given to the clients" I meant by the SSSD daemon. Sorry for the
confusion with how I typed up my scenario. What I am not understanding
is how setting the default domain in the configuration prevents
non-deterministic handling of slice collisions. The man page states:
"NOTE: It is possible to encounter collisions in the hash and
subsequent modulus. In these situations, we will select the next
available slice, but it may not be possible to reproduce the same
exact set of slices on other machines (since the order that they are
encountered will determine their slice). In this situation, it is
recommended to..... <snip> ..... configure a default domain to
guarantee that at least one is always consistent."
How does having one domain always be slice 0 resolve the other domains
possibly not being consistent? Or is the "at least" in the man page
saying that users of the domain assigned to slice 0 will always have
the same UID's, but not necessarily users in the other domains?
Also, of course, in the non-default domains I'm referring to this issue
only in the event of collisions. I understand that normally domains hash
out to deterministic slices.