Re: [Xen-devel] [PATCH 4/4] docs: Document xenstore paths for domain network address information

[Paul Durrant <Paul.Durrant@xxxxxxxxxx>]

> -----Original Message-----
> From: Andrew Cooper [mailto:andrew.cooper3@xxxxxxxxxx]
> Sent: 06 November 2015 18:17
> To: Paul Durrant; xen-devel@xxxxxxxxxxxxxxxxxxxx
> Cc: Keir (Xen.org); Ian Campbell; Tim (Xen.org); Ian Jackson; Jan Beulich
> Subject: Re: [Xen-devel] [PATCH 4/4] docs: Document xenstore paths for
> domain network address information
> 
> On 06/11/15 17:21, Paul Durrant wrote:
> > It is useful to be able to see the network addresses in use by a domain
> > for a particular vif in xenstore, for example so that ssh can be invoked
> > by a toolstack to log into the guest domain.
> >
> > This patch documents paths to allow a domain to advertise MAC (unicast
> > and multicast) and IP (versions 4 and 6) address information.
> >
> > Signed-off-by: Paul Durrant <paul.durrant@xxxxxxxxxx>
> > Cc: Ian Campbell <ian.campbell@xxxxxxxxxx>
> > Cc: Ian Jackson <ian.jackson@xxxxxxxxxxxxx>
> > Cc: Jan Beulich <jbeulich@xxxxxxxx>
> > Cc: Keir Fraser <keir@xxxxxxx>
> > Cc: Tim Deegan <tim@xxxxxxx>
> > ---
> >  docs/misc/xenstore-paths.markdown | 29
> +++++++++++++++++++++++++++++
> >  1 file changed, 29 insertions(+)
> >
> > diff --git a/docs/misc/xenstore-paths.markdown b/docs/misc/xenstore-
> paths.markdown
> > index 9e98d6f..68d3dbf 100644
> > --- a/docs/misc/xenstore-paths.markdown
> > +++ b/docs/misc/xenstore-paths.markdown
> > @@ -39,6 +39,8 @@ before regexp expansion:
> >  * $UUID -- a UUID in the form xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
> >  * $NAME -- a string identifying an object within a domain. Typically
> >    comprising only alphanumeric characters.
> > +* $INDEX -- an integer used as part of a path when listing a set of
> > +            values. Typically these integers are contiguous.
> >
> >  VALUES are strings and can take the following forms:
> >
> > @@ -56,6 +58,13 @@ VALUES are strings and can take the following forms:
> >  * VERSION -- 2 or 3 integers, in decimal form separated by ".",
> >               specifying major version, minor version, and then
> >          (optionally) micro version.
> > +* MAC_ADDRESS -- 6 integers, in hexadecimal form, separated by ':',
> > +                 specifying an ethernet MAC address.
> > +* IPV4_ADDRESS -- 4 integers, in decimal form, separated by '.',
> > +                  specifying an IP version 4 address.
> > +* IPV6_ADDRESS -- 8 integers, in hexadecimal form, separated by ':',
> > +                  specifying an IP version 6 address. (There should
> > +                  be strictly 8 integers i.e. '::' compression).
> 
> Given the "strictly", I presume you mean no "::" compression?

Yes, I missed the 'no'

> 
> But why enforce that restriction? "::" compression is unambiguous and
> typically makes the addresses rather more human readable.
> 

That's true but I didn't want to put the coding burden on the frontend. 
Defining it this way makes it a trivial printf into xenstore. Whatever picks 
the address up can do the compression afterwards before display. I suppose it 
would be better to allow compression but state that it's not required.

  Paul

> ~Andrew

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel